Reliability Standards To Address Inverter-Based Resources, 74541-74563 [2022-25599]

Agencies

• DEPARTMENT OF ENERGY
• Federal Energy Regulatory Commission

[Federal Register Volume 87, Number 233 (Tuesday, December 6, 2022)]
[Proposed Rules]
[Pages 74541-74563]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-25599]


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DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

18 CFR Part 40

[Docket No. RM22-12-000]


Reliability Standards To Address Inverter-Based Resources

AGENCY: Federal Energy Regulatory Commission, Department of Energy 
(DOE).

ACTION: Notice of proposed rulemaking.

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SUMMARY: The Federal Energy Regulatory Commission (Commission) proposes 
to direct the North American Electric Reliability Corporation (NERC), 
the Commission-certified Electric Reliability Organization (ERO), to 
develop new or modified Reliability Standards that address the 
following reliability gaps related to inverter-based resources (IBR): 
data sharing; model validation; planning and operational studies; and 
performance requirements. Further, the Commission proposes to direct 
NERC to submit to the Commission a compliance filing within 90 days of 
the effective date of the final rule in this proceeding that includes a 
detailed, comprehensive standards development and implementation plan 
to ensure all new or modified Reliability Standards necessary to 
address the IBR-related reliability gaps identified in the final rule 
are submitted to the Commission within 36 months of Commission approval 
of the plan.

DATES: Comments are due February 6, 2023 and reply Comments are due 
March 6, 2023.

ADDRESSES: Comments, identified by docket number, may be filed in the 
following ways. Electronic filing through https://www.ferc.gov, is 
preferred.
     Electronic Filing: Documents must be filed in acceptable 
native applications and print-to-PDF, but not in scanned or picture 
format.
     For those unable to file electronically, comments may be 
filed by U.S. Postal Service mail or by hand (including courier) 
delivery.
    [cir] Mail via U.S. Postal Service only: Addressed to: Federal 
Energy Regulatory Commission, Office of the Secretary, 888 First Street 
NE, Washington, DC 20426.
    [cir] For Delivery via Any Other Carrier (including courier): 
Deliver to: Federal Energy Regulatory Commission, Office of the 
Secretary, 12225 Wilkins Avenue, Rockville, MD 20852.

FOR FURTHER INFORMATION CONTACT: 
    Eugene Blick (Technical Information), Office of Electric 
Reliability, Federal Energy Regulatory Commission, 888 First Street NE, 
Washington, DC 20426, (202) 502-8803, [email protected].
    Alan J. Rukin (Legal Information), Office of the General Counsel, 
Federal Energy Regulatory Commission, 888 First Street NE, Washington, 
DC 20426, (202) 502-8502, [email protected].

SUPPLEMENTARY INFORMATION: 

Table of Contents

 
                                                              Paragraph
                                                                 Nos.
 
I. Introduction............................................            1
II. Background.............................................           10
    A. Legal Authority.....................................           10
    B. Reliability Impacts of IBR Technologies.............           12
    C. Actions To Address the Reliability Impact of IBR               17
     Technologies..........................................
III. The Need for Reform...................................           24
    A. Recent Events Show IBR-Related Adverse Reliability             24
     Impacts on the Bulk-Power System......................
    B. Reliability Standards Do Not Adequately Address IBR            27
     Reliability Risks.....................................
        1. Data Sharing....................................           27
        2. IBR and IBR-DER Data and Model Validation.......           33

[[Page 74542]]

 
        3. IBR and IBR-DER Planning and Operational Studies           47
        4. IBR Performance.................................           54
IV. Proposed Directives....................................           68
    A. IBR and IBR-DER Data Sharing........................           76
    B. IBR and IBR-DER Data and Model Validation...........           82
    C. IBR and IBR-DER Planning and Operational Studies....           87
        1. Planning Studies................................           88
        2. Operational Studies.............................           89
    D. IBR Performance Requirements........................           90
        1. Frequency Ride Through..........................           93
        2. Voltage Ride Through............................           94
        3. Post-Disturbance IBR Ramp Rate Interactions.....           96
        4. Phase Lock Loop Synchronization.................           97
V. Information Collection Statement........................           98
VI. Environmental Assessment...............................          101
VII. Regulatory Flexibility Act Certification..............          102
VIII. Comment Procedures...................................          104
IX. Document Availability..................................          108
 

I. Introduction

    1. Pursuant to section 215(d)(5) of the Federal Power Act (FPA),\1\ 
the Commission proposes to direct NERC, the Commission-certified ERO, 
to submit new or modified Reliability Standards that address concerns 
pertaining to the impacts of IBRs \2\ on the reliable operation \3\ of 
the Bulk-Power System.\4\ The Commission proposes to direct NERC to 
develop new or modified Reliability Standards addressing four 
reliability gaps pertaining to IBRs: (1) data sharing; (2) model 
validation; (3) planning and operational studies; and (4) performance 
requirements.
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    \1\ 16 U.S.C. 824o(d)(5); 18 CFR 39.5(f).
    \2\ This notice of proposed rulemaking (NOPR) uses the term IBR 
generally to include all generation resources that connect to the 
electric power system using power electronic devices that change 
direct current (DC) power produced by a resource to alternating 
current (AC) power compatible with distribution and transmission 
grids. IBRs may refer to solar photovoltaic (PV), wind, fuel cell, 
and battery storage resources.
    \3\ The FPA defines reliable operation as operating the elements 
of the Bulk-Power System within equipment and electric system 
thermal, voltage, and stability limits so that instability, 
uncontrolled separation, or cascading failures of such system will 
not occur as a result of a sudden disturbance, including a 
cybersecurity incident, or unanticipated failure of system elements. 
16 U.S.C. 824o(a)(4); see also 18 CFR 39.1.
    \4\ The Bulk-Power System is defined in the FPA as facilities 
and control systems necessary for operating an interconnected 
electric energy transmission network (or any portion thereof), and 
electric energy from generating facilities needed to maintain 
transmission system reliability. The term does not include 
facilities used in the local distribution of electric energy. 16 
U.S.C. 824o(a)(1); see also 18 CFR 39.1.
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    2. We take this action in view of the rapid change in the 
generation resource mix currently underway on the Bulk-Power System, 
including the addition of an ``unprecedented proportion of 
nonsynchronous resources'' \5\ projected over the next decade, 
including many resources that employ inverters and converters \6\ to 
provide energy to the Bulk-Power System. According to NERC, the rapid 
integration of IBRs is ``the most significant driver of grid 
transformation'' on the Bulk-Power System.\7\ While IBRs provide many 
benefits, they also present new considerations for transmission 
planning and operation of the Bulk-Power System.
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    \5\ NERC, 2020 Long Term Reliability Assessment Report, 9 (Dec. 
2020), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf (2020 LTRA 
Report).
    \6\ An inverter is a power electronic device that inverts DC 
power to AC sinusoidal power through solid state switches. A 
converter is a power electronic device that converts AC sinusoidal 
power to DC power through solid state switches. Consistent with 
NERC's terminology, this order uses the term ``inverter'' to refer 
to generating facilities that use power electronic inversion and 
conversion. NERC, Inverter-Based Resource Performance and Analysis 
Technical Workshop, 29 (Feb. 2019), https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf.
    \7\ NERC, Inverter-Based Resource Strategy: Ensuring Reliability 
of the Bulk Power System with Increased Levels of BPS-Connected 
IBRs, 1 (Sept. 2022), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf (NERC IBR Strategy).
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    3. IBRs can produce real and reactive power like synchronous 
generators, but IBRs do not react to disturbances on the Bulk-Power 
System in the same way. For example, synchronous resources that are not 
connected to a fault will automatically ride through \8\ a disturbance 
because they are synchronized (i.e., connected at identical speeds) to 
the electric power system and physically linked to support the system 
voltage or frequency during voltage or frequency fluctuations by 
continuing to produce real and reactive power. In contrast, IBRs are 
not directly synchronized to the electric power system and must be 
programmed to support the electric power system and to ride through a 
disturbance. The operational characteristics of IBRs coupled with their 
equipment settings may cause them to reduce power output, whether by 
tripping offline \9\ or ceasing operation without tripping offline 
(known as momentary cessation),\10\ individually or in the aggregate in 
response to response to a single fault on a transmission or sub-
transmission system. Such occurrences may exacerbate system 
disturbances and have a material impact on the reliable operation of 
the Bulk-Power System.
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    \8\ See Standardization of Generator Interconnection Agreements 
& Procs., Order No. 2003, 68 FR 49846 (Aug. 19, 2003), 104 FERC ] 
61,103, at P 562 n.88, (2003) (defining ride through as ``a 
Generating Facility staying connected to and synchronized with the 
Transmission System during system disturbances within a range of 
over- and under-frequency[/voltage] conditions, in accordance with 
Good Utility Practice.'').
    \9\ Tripping offline is a mode of operation during which part of 
or the entire IBR disconnects from the Bulk-Power System and/or 
distribution system and therefore cannot supply real and reactive 
power.
    \10\ Momentary cessation is a mode of operation during which the 
inverter remains electrically connected to the Bulk-Power System, 
but the inverter does not inject current during low or high voltage 
conditions outside the continuous operating range. As a result, 
there is no current injection from the inverter and therefore no 
active or reactive current (and no active or reactive power). NERC, 
Reliability Guideline: Bulk-Power System-Connected Inverter-Based 
Resource Performance, 11 (Sept. 2018), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf (IBR Performance 
Guideline).
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    4. The mandatory and enforceable Reliability Standards were 
developed to apply to the generation resources prevalent at the time 
that the standards were developed and adopted--nearly exclusively 
synchronous generation resources--and ensure the reliable operation of 
the Bulk-Power System. As a result, the Reliability Standards may

[[Page 74543]]

not account for the material technological differences between the 
response of synchronous generation resources and that of IBRs to the 
same disturbances on the Bulk-Power System.\11\ Illustratively, at 
least 12 events on the Bulk-Power System \12\ have demonstrated common 
mode failures of IBRs regardless of their size or voltage connection, 
acting unexpectedly and adversely in response to normally cleared 
transmission line faults on the Bulk-Power System.\13\ Further, 
simulations indicate that IBR momentary cessation occurring in the 
aggregate can lead to instability, system-wide uncontrolled separation, 
and voltage collapse.\14\
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    \11\ See, e.g., NERC, 2013 Long-Term Reliability Assessment, 22 
(Dec. 2013), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf (2013 LTRA 
Report) (finding that reliably integrating high levels of variable 
resources into the Bulk-Power System would require ``significant 
changes to traditional methods used for system planning and 
operation,'' including requiring ``new tools and practices, 
including potential enhancements to . . . Reliability Standards or 
guidelines to maintain [Bulk-Power System] reliability.'').
    \12\ The 12 events report an average of approximately 1,000 MW 
of IBRs entering into momentary cessation or tripping in the 
aggregate. The 12 Bulk-Power System events are: (1) the Blue Cut 
Fire (August 16, 2016); (2) the Canyon 2 Fire (October 9, 2017); (3) 
Angeles Forest (April 20, 2018); (4) Palmdale Roost (May 11, 2018); 
(5) San Fernando (July 7, 2020); (6) the first Odessa, Texas event 
(May 9, 2021); (7) the second Odessa, Texas event (June 26, 2021); 
(8) Victorville (June 24, 2021); (9) Tumbleweed (July 4, 2021); (10) 
Windhub (July 28, 2021); (11) Lytle Creek (August 26, 2021), and 
(12) Panhandle Wind Disturbance (March 22, 2022).
    \13\ The Bulk-Power System's sensing devices usually respond 
slowly, and therefore, are likely underreporting the size of the IBR 
generation loss during disturbances. See, e.g., NERC and Western 
Electricity Coordinating Council (WECC), 900 MW Fault Induced Solar 
Photovoltaic Resource Interruption Disturbance Report, 1 n.6 (Feb. 
2018), https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf (Canyon 2 Fire Event Report) (explaining that MW 
loss values are based on supervisory control and data acquisition 
(SCADA), which does not capture momentary cessation). NERC only 
tracks ``Category 1'' events, which are unexpected outages of three 
or more bulk electric system facilities, including interruptions of 
IBRs aggregated to a 500 MW threshold (Category 1aii and Category 
1i). NERC, ERO Event Analysis Process--Version 4.0, 2 (Dec. 2019), 
https://www.nerc.com/pa/rrm/ea/ERO_EAP_Documents%20DL/ERO_EAP_v4.0_final.pdf.
    \14\ See NERC, Resource Loss Protection Criteria Assessment 
Whitepaper, (Feb. 2018), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf (Resource Loss Protection Whitepaper) 
(demonstrating the impacts of momentary cessation risks to Bulk-
Power System reliability through simulations).
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    5. We preliminarily find that the Reliability Standards may not 
provide Bulk-Power System planners or operators with the tools 
necessary to plan for and reliably integrate IBRs into the Bulk-Power 
System. Further, we preliminarily find that the Reliability Standards 
may not provide Bulk-Power System planners or operators with the tools 
necessary to plan for IBR-DERs connected to the distribution system 
that, when acting in the aggregate, can have a material impact on the 
reliable operation of the Bulk-Power System. Additionally, we 
preliminary find that the Reliability Standards do not delineate all of 
the performance requirements that are unique to IBRs and are necessary 
to ensure that IBRs operate in a predictable and reliable manner. We 
propose to act to ensure the continued reliable operation of the Bulk-
Power System in response to current, and in anticipation of greater, 
IBR penetration onto the Bulk-Power System. We therefore propose, 
pursuant to section 215(d)(5) of the FPA and Sec.  39.5(f) of the 
Commission's regulations, to direct NERC to develop new or modified 
Reliability Standards that address the following specific matters for 
IBRs: \15\
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    \15\ Various NERC reports do not always differentiate between 
IBRs based on type, or between those subject to Reliability 
Standards and those located on the distribution system. Where 
necessary to qualify our proposed directives, however, we 
differentiate between IBRs registered with NERC and therefore 
subject to the Reliability Standards because they fall within the 
bulk electric system definition (registered IBRs) from those 
connected directly to the Bulk-Power System but not registered with 
NERC and therefore not subject to the Reliability Standards 
(unregistered IBRs), and those connected to the distribution system 
(IBR-DER). NERC's Commission-approved bulk electric system 
definition is a subset of the Bulk-Power System and defines the 
scope of the Reliability Standards and the entities subject to NERC 
compliance. Revisions to Electric Reliability Org. Definition of 
Bulk Elec. Sys. & Rules of Proc., Order No. 773, 78 FR 804 (Jan. 4, 
2013), 141 FERC ] 61,236 (2012) order on reh'g, Order No. 773-A, 78 
FR 29209 (May 17, 2013), 143 FERC ] 61,053 (2013) rev'd sub nom. 
People of the State of N.Y. v. FERC, 783 F.3d 946 (2d Cir. 2015); 
NERC, Glossary of Terms Used in NERC Reliability Standards, 5-7 
(Mar. 29, 2022), https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf (NERC Glossary).
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     IBR Data Sharing: The Reliability Standards should ensure 
that NERC registered entities,\16\ such as planning coordinators and 
reliability coordinators, have the necessary data to predict the 
behavior of all IBRs, including unregistered IBRs and IBR-DERs, and 
their impact on the reliable operation of the Bulk-Power System. To 
achieve this, the Reliability Standards should ensure that generator 
owners, transmission owners, and distribution providers are required to 
share validated modeling, planning, operations, and disturbance 
monitoring data for IBRs with planning coordinators, transmission 
planners, reliability coordinators, transmission operators, and 
balancing authorities.
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    \16\ NERC identifies and registers Bulk-Power System users, 
owners, and operators who are responsible for performing specified 
reliability functions to which requirements of mandatory Reliability 
Standards are applicable. See NERC Rules of Procedure, Section 500 
(Organization Registration and Certification).
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     IBR Model Validation: The Reliability Standards should 
ensure that IBR models are comprehensive, validated, and updated in a 
timely manner, so that they can adequately predict the behavior of all 
IBRs, including unregistered IBRs and IBR-DERs, and their impacts on 
the reliable operation of the Bulk-Power System.
     IBR Planning and Operational Studies: The Reliability 
Standards should ensure that validated IBR models are included in 
planning and operational studies to assess the reliability impacts on 
Bulk-Power System performance by registered IBRs and unregistered IBRs, 
both individually and in the aggregate, as well as IBR-DERs in the 
aggregate. The Reliability Standards should ensure that planning and 
operational studies assess the impacts of all IBRs within and across 
planning and operational boundaries for normal operations and 
contingency event conditions.
     IBR Performance Requirements: The Reliability Standards 
should ensure that registered IBRs provide frequency and voltage 
support during frequency and voltage excursions in a manner necessary 
to contribute toward the overall system needs for essential reliability 
services.\17\ The Reliability Standards should establish clear and 
reliable technical limits and capabilities for registered IBRs to 
ensure that all registered IBRs are operated in a predictable and 
reliable manner during: (1) normal operations; and (2) contingency 
event conditions. The Reliability Standards should require that the 
engineering and operational aspects of registered IBRs necessary to 
contribute toward the overall system needs for essential reliability 
services include registered IBR post-disturbance ramp rates and phase-
locked loop synchronization.
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    \17\ See, e.g., NERC, A Concept Paper on Essential Reliability 
Services that Characterizes Bulk Power System Reliability, vi (Oct. 
2014), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf (Essential Reliability Services Concept 
Paper) (listing the essential reliability services necessary to 
maintain Bulk-Power System reliability).
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    6. In proposing to direct that NERC develop one or more new 
Reliability

[[Page 74544]]

Standards or modify currently effective Reliability Standards to 
address the gaps identified in this rulemaking, we are not proposing 
specific requirements. Instead, we identify concerns that we believe 
the Reliability Standards should address. In its petition accompanying 
any new or modified Reliability Standards, NERC should explain how the 
new or modified Reliability Standards address the Commission's 
concerns.\18\ We invite comments on these concerns and whether there 
are other concerns related to planning for and integrating IBRs that 
the Commission should direct NERC to address in this or a future 
proceeding.
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    \18\ See, e.g., Mandatory Reliability Standards for the Bulk-
Power Sys., Order No. 693, 72 FR 16416 (Apr. 4, 2007), 118 FERC ] 
61,218, at PP 186, 297, order on reh'g, Order No. 693-A, 72 FR 40717 
(July 25, 2007), 120 FERC ] 61,053 (2007) (``where the Final Rule 
identifies a concern and offers a specific approach to address the 
concern, we will consider an equivalent alternative approach 
provided that the ERO demonstrates that the alternative will address 
the Commission's underlying concern or goal as efficiently and 
effectively as the Commission's proposal'').
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    7. We propose to direct NERC to submit a compliance filing within 
90 days of the effective date of the final rule in this proceeding. 
That compliance filing shall include a detailed, comprehensive 
standards development and implementation plan explaining how NERC will 
prioritize the development and implementation of new or modified 
Reliability Standards. In its compliance filing, NERC should explain 
how it is prioritizing its IBR Reliability Standard projects to meet 
the directives in the final rule, taking into account the risk posed to 
the reliability of the Bulk-Power System, standard development projects 
already underway, resource constraints, and other factors if necessary.
    8. We seek comment on the proposal to direct NERC to use a 
staggered approach that would result in NERC submitting new or modified 
Reliability Standards in three stages: (1) new or modified Reliability 
Standards including directives related to registered IBR failures to 
ride through frequency and voltage variations during normally cleared 
Bulk-Power System faults shall be filed with the Commission within 12 
months of Commission approval of the plan; (2) new or modified 
Reliability Standards addressing the interconnected directives related 
to registered IBR, unregistered IBR, and IBR-DER data sharing, 
registered IBR disturbance monitoring data sharing, registered IBR, 
unregistered IBR, and IBR-DER data and model validation, and registered 
IBR, unregistered IBR, and IBR-DER planning and operational studies 
shall be filed with the Commission within 24 months of Commission 
approval of the plan; and (3) new or modified Reliability Standards 
including the remaining directives for post-disturbance ramp rates and 
phase-locked loop synchronization shall be filed with the Commission 
within 36 months of Commission approval of the plan. We believe this 
staggered approach to standard development may be necessary based on 
the scope of work anticipated and that specific target dates will 
provide a valuable tool and incentive to NERC to timely address the 
directives in the final rule. This proposal strikes a reasonable 
balance between the need to timely implement identified improvements to 
the Reliability Standards that will further Bulk-Power System 
reliability and the need for NERC to develop modifications with 
appropriate stakeholder input using its open stakeholder process.
    9. In view of the rapid growth of IBRs connected to the Bulk-Power 
System, we are issuing this NOPR concurrently with a separate order in 
Docket No. RD22-4-000 directing NERC to address the registration of 
owners and operators of unregistered IBRs that may have a material 
impact on the reliable operation of the Bulk-Power System.\19\ That 
order addresses the registration of unregistered IBRs that individually 
fall outside of the bulk electric system definition, are connected 
directly to the Bulk-Power System, and that in the aggregate have a 
material impact on the reliable operation of the Bulk-Power System.
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    \19\ See Registration of Inverter-based Resources, 181 FERC ] 
61,124 (2022).
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II. Background

A. Legal Authority

    10. Section 215 of the FPA provides that the Commission may certify 
an ERO, the purpose of which is to establish and enforce Reliability 
Standards, which are subject to Commission review and approval. 
Reliability Standards may be enforced by the ERO, subject to Commission 
oversight, or by the Commission independently.\20\ Pursuant to section 
215 of the FPA, the Commission established a process to select and 
certify an ERO,\21\ and subsequently certified NERC as the ERO.\22\
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    \20\ 16 U.S.C. 824o(e).
    \21\ Rules Concerning Certification of the Elec. Reliability 
Org. & Procs. for the Establishment, Approval, & Enf't of Elec. 
Reliability Standards, Order No. 672, 71 FR 8662 (Feb. 17, 2006), 
114 FERC ] 61,104, order on reh'g, Order No. 672-A, 71 FR 19814 
(Apr. 18, 2006), 114 FERC ] 61,328 (2006).
    \22\ N. Am. Elec. Reliability Corp., 116 FERC ] 61,062, order on 
reh'g and compliance, 117 FERC ] 61,126 (2006), aff'd sub nom. 
Alcoa, Inc. v. FERC, 564 F.3d 1342 (DC Cir. 2009).
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    11. The Commission has the authority pursuant to section 215(d)(5) 
of the FPA and consistent with Sec.  39.5(f) of the Commission's 
regulations, upon its own motion or upon complaint, to order the ERO to 
submit to the Commission a proposed Reliability Standard or a 
modification to a Reliability Standard that addresses a specific matter 
if the Commission considers such a new or modified Reliability Standard 
appropriate to carry out section 215 of the FPA.\23\ Further, pursuant 
to Sec.  39.5(g) of the Commission's regulations, when ordering the ERO 
to submit to the Commission a proposed or modified Reliability Standard 
that addresses a specific matter, the Commission may order a deadline 
by which the ERO must submit such Reliability Standard.\24\
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    \23\ 16 U.S.C. 824o(d)(5); 18 CFR 39.5(f).
    \24\ 18 CFR 39.5(g).
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B. Reliability Impacts of IBR Technologies

    12. Until recently, the Bulk-Power System generation fleet was 
composed almost exclusively of synchronous generation resources \25\ 
that convert mechanical energy into electric energy through 
electromagnetic induction. By virtue of their large rotating elements, 
these synchronous generation resources inherently resist changes in 
system frequency due to the kinetic energy in their rotating 
components, providing time for other governor controls (when properly 
configured) to maintain supply and load balance. Similarly, synchronous 
generation resources can provide voltage support during voltage 
disturbances.
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    \25\ The Reliability Standards use both terms ``generation 
resources'' and ``generation facilities'' to define sources of 
electric power on the transmission system. In this NOPR, we use the 
terms ``generation resources'' and ``generation facilities'' 
interchangeably.
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    13. In contrast, IBRs do not use electromagnetic induction from 
machinery that is directly synchronized to the Bulk-Power System. 
Instead, IBRs predominantly use grid-following inverters, which rely on 
sensed information from the grid (e.g., a voltage waveform) in order to 
produce the desired AC real and reactive power

[[Page 74545]]

output.\26\ IBRs can track grid state parameters (e.g., voltage angle) 
on the order of milli-seconds and react nearly instantaneously to 
changing grid conditions. Some IBRs, however, are not configured or 
programmed to support grid voltage and frequency and, as a result, will 
reduce power,\27\ exhibit momentary cessation, or trip in response to 
variations in system voltage or frequency.\28\ In other words, under 
certain conditions some IBRs cease to provide power to the Bulk-Power 
System due to how they are configured and programmed even though some 
models and simulations predict that IBRs maintain real power output and 
provide voltage and frequency support consistent with Reliability 
Standard PRC-024-2 (Generator Frequency and Voltage Protective Relay 
Settings).
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    \26\ See, e.g., NERC, 2021 Long Term Reliability Assessment 
Report, 6 (Dec. 2021), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf (2021 LTRA Report) 
(``IBRs respond to disturbances and dynamic conditions based on 
programmed logic and inverter controls, not mechanical 
characteristics.''); see also generally, Denholm et al., National 
Renewable Energy Laboratory, Inertia and the Power Grid: A Guide 
Without the Spin, NREL/TP-6120-73856, v (2020), https://www.nrel.gov/docs/fy20osti/73856.pdf.
    \27\ NERC and WECC, San Fernando Disturbance, 2 (Nov. 2020), 
https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf (San Fernando Disturbance 
Report).
    \28\ See Essential Reliability Servs. & the Evolving Bulk-Power 
Sys. Primary Frequency Response, Order No. 842, 83 FR 9636 (Mar. 6, 
2018), 162 FERC ] 61,128 , at P 19 (2018) (describing NERC's comment 
that increased IBR deployment alongside retirement of synchronous 
generation resources has contributed to the decline in primary 
frequency response); see also NERC, Fast Frequency Response Concepts 
and Bulk Power System Reliability Needs, 5 (Mar. 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf (Fast Frequency Response White Paper) (explaining that as the 
instantaneous penetration of IBRs with little or no inertia 
continues to increase, system rate of change of frequency after a 
loss of generation will increase and the time available to deliver 
frequency responsive reserves will shorten, and illustrating the 
steeper rate of change of frequency and the importance of speed of 
response).
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    14. IBRs are also more dispersed across the Bulk-Power System 
compared to synchronous generation resources, and both localized and 
interconnection-wide IBR issues must be identified, studied, and 
mitigated to preserve Bulk-Power System reliability. Although IBRs are 
typically smaller-megawatt (MW) facilities, they are at greater risk 
than synchronous generation resources of being lost (i.e., ceasing to 
provide power to the Bulk-Power System) in the aggregate in response to 
a single fault on the transmission or sub-transmission systems. Such 
response can occur when individual IBR controls and equipment 
protection settings are not configured to ride through system 
disturbances.\29\ Thus, the impact of IBRs is not restricted by the 
size of a single facility or an individual balancing authority area, 
but rather by the number of IBRs or percent of generation made up by 
IBRs within an interconnection. In areas of high IBR saturation, this 
type of aggregate response may have an impact much greater than the 
most severe single contingency (i.e., the traditional worst-case N-1 
contingency) \30\ of a balancing authority area, potentially adversely 
affecting other balancing authority areas across an 
interconnection.\31\ Unless IBRs are configured and programmed to ride 
through normally cleared transmission faults, the potential impact of 
losing IBRs individually or in the aggregate will continue to increase 
as IBRs are added to the Bulk-Power System and make up an increasing 
proportion of the resource mix.
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    \29\ See, e.g., Canyon 2 Fire Event Report at 19 (finding 
momentary cessation as a major cause for the loss of IBRs when 
voltages rose above 1.1 per unit or decreased below 0.9 per unit).
    \30\ The most severe single contingency, or the N-1 contingency, 
generally refers to the concept that a system must be able to 
withstand an unexpected failure or outage of a single system 
component and maintain reliable service at all times. See, e.g., 
NERC Glossary at 17 (defining ``most severe single contingency'').
    \31\ See, e.g., San Fernando Disturbance Report at vi (stating 
that ``[t]his event, as with past events, involved a significant 
number of solar PV resources reducing power output (either due to 
momentary cessation or inverter tripping) as a result of normally-
cleared [Bulk-Power System] faults. The widespread nature of power 
reduction across many facilities poses risks to [Bulk-Power System] 
performance and reliability.'').
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    15. Further, simulations conducted by the NERC Resource 
Subcommittee demonstrate that the risks to Bulk-Power System 
reliability posed by momentary cessation are greater than any of the 
IBR disturbances NERC has documented as being experienced thus far. 
These simulations indicate the potential for: (1) normally-cleared, 
three-phase faults at certain locations in the Western Interconnection 
that could result in upwards of 9,000 MW of solar PV IBRs entering 
momentary cessation across a large geographic region; (2) transient 
instability caused by excessive transfer of inter-area power flows 
during and after momentary cessation; and (3) a drop in frequency that 
falls below the first stage of under frequency load shedding in WECC, 
traditionally studied as the loss of the two Palo Verde nuclear units 
in Arizona (approximately 2,600 MW).\32\ These simulation results 
indicate that IBR momentary cessation occurring in the aggregate can 
lead to instability, system-wide uncontrolled separation, and voltage 
collapse.
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    \32\ Resource Loss Protection Whitepaper at 1-2, key findings 4, 
7, 8.
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    16. Although IBRs present risks that Bulk-Power System planners and 
operators must account for, IBRs also present new opportunities to 
support the grid and respond to abnormal grid conditions.\33\ When 
appropriately programmed, IBRs can operate during greater frequency 
deviations (i.e., a wider frequency range) than synchronous generation 
resources.\34\ This operational flexibility, and the ability of IBRs to 
perform with precision and speed, offers increased Bulk-Power System 
performance capabilities and controls that could mitigate disturbances 
on the Bulk-Power System. For Bulk-Power System operators to harness 
the unique performance and control capabilities of IBRs, these 
resources must be properly configured and programmed to support grid 
voltage and frequency during normal and abnormal grid conditions and be 
accurately modeled and represented in transmission planning and 
operations models.
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    \33\ See, e.g., IBR Performance Guideline at vii (finding that 
the power electronics aspects of IBRs ``present new opportunities in 
terms of grid control and response to abnormal grid conditions.'').
    \34\ See, e.g., Fast Frequency Response White Paper at 11.
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C. Actions To Address the Reliability Impact of IBR Technologies

    17. NERC has begun to address some of the reliability risk posed by 
IBRs. Specifically, since the first documented disturbance event on the 
Bulk-Power System demonstrating common mode failures of IBRs in 2016, 
NERC has: (1) published seven reports on 12 disturbance events; \35\ 
(2) issued two

[[Page 74546]]

NERC Alerts addressing the loss of solar PV IBRs; \36\ (3) issued three 
reliability guidelines; \37\ (4) formed the IBR performance task force 
(IRPTF) \38\ and a system planning impacts of distributed energy 
resources working group (SPIDERWG); (5) issued various technical 
reports regarding IBR data collection and performance; \39\ and (6) 
issued an IBR strategy document.\40\ The NERC materials (e.g., 
guidelines, whitepapers, reports, alerts, etc.) cited in this NOPR are 
also listed in Appendix A as a reference. Appendix A will not appear in 
the Federal Register. Appendix A will be available separately on the 
Commission's website.\41\
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    \35\ The seven reports on the 12 disturbances are:
    (1) NERC, 1,200 MW Fault Induced Solar Photovoltaic Resource 
Interruption Disturbance Report (June 2017), https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf (Blue Cut Fire Event Report) (covering the Blue Cut Fire event 
(August 16, 2016));
    (2) Canyon 2 Fire Event Report (covering the Canyon 2 Fire event 
(October 9, 2017));
    (3) NERC and WECC, April and May 2018 Fault Induced Solar 
Photovoltaic Resource Interruption Disturbances Report (Jan. 2019), 
(Angeles Forest and Palmdale Roost Events Report), https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf (Angeles Forest and 
Palmdale Roost Events Report) (covering the Angeles Forest (April 
20, 2018) and Palmdale Roost (May 11, 2018) events);
    (4) San Fernando Disturbance Report (covering the San Fernando 
event (July 7, 2020));
    (5) NERC and Texas RE, Odessa Disturbance (Sept. 2021), https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf 
(Odessa Disturbance Report) (covering events in Odessa, Texas on May 
9, 2021 and June 26, 2021);
    (6) NERC and WECC, Multiple Solar PV Disturbances in CAISO 
(April 2022), https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf (2021 Solar PV 
Disturbances Report) (covering four events: Victorville (June 24, 
2021); Tumbleweed (July 4, 2021); Windhub (July 28, 2021); and Lytle 
Creek (August 26, 2021)); and
    (7) NERC and Texas RE, March 2022 Panhandle Wind Disturbance 
Report (August 2022), https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf (Panhandle Report) (covering 
the Texas Panhandle event (March 22, 2022)).
    \36\ NERC, Industry Recommendation: Loss of Solar Resources 
during Transmission Disturbances due to Inverter Settings (June 
2017), https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20Loss%20of%20Solar%20Resources%20during%20Transmission%20Disturbance.pdf (Loss of Solar Resources Alert I); NERC, Industry 
Recommendation Loss of Solar Resources during Transmission 
Disturbances due to Inverter Settings--II (May 2018), https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf (Loss of Solar Resources Alert II).
    \37\ See IBR Performance Guideline; NERC, Reliability Guideline: 
Improvements to Interconnection Requirements for BPS-Connected 
Inverter-Based Resources (Sept. 2019), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf (IBR Interconnection Requirements Guideline); NERC, Reliability 
Guideline: Performance, Modeling, and Simulations of Bulk-Power 
System-Connected Battery Energy Storage Systems and Hybrid Power 
Plants (Mar. 2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf 
(BESS Performance Modeling Guideline).
    \38\ The task force later became the IBR Performance Working 
Group in October 2020, and most recently became the IBR Performance 
Subcommittee in March 2022. For consistency, this NOPR uses 
``IRPTF'' to refer to all three iterations.
    \39\ See, e.g., NERC, Technical Report, Bulk-Power System-
Connected Inverter-Based Resource Modeling and Studies, (May 2020), 
https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf (Modeling and Studies Report); 
NERC and WECC, WECC Base Case Review: Inverter-Based Resources (Aug. 
2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf (Western Interconnection (WI) Base 
Case IBR Review).
    \40\ NERC IBR Strategy, (July 2021), https://www.nerc.com/FilingsOrders/us/NERC%20Filings%20to%20FERC%20DL/2022-2024%20RSDP%20FERC%20Filing.pdf.
    \41\ Federal Energy Regulatory Commission, Table of Cited NERC 
IBR Resources (RM22-12-000), https://www.ferc.gov/media/table-cited-nerc-ibr-resources-rm22-12-000.
---------------------------------------------------------------------------

    18. The only NERC actions that required a response from entities 
are the two NERC alerts addressing the loss of solar PV IBRs (both 
alerts were level 2 alerts, ``Recommendation to Industry'').\42\ These 
NERC level 2 alerts recommended specific voluntary action to be taken 
by registered IBRs and required that the registered IBRs provide 
responsive information to NERC. While unregistered IBRs could also 
voluntarily take the specific actions set out in the level 2 alert, 
there was no reporting requirement for unregistered IBRs due to NERC's 
authority to require reporting responses only from registered IBRs. 
NERC issued these alerts to assess the scope of and recommend 
performance actions to address registered IBR reliability risks to the 
Bulk-Power System. NERC issued its first alert in 2017 after the Blue 
Cut Fire Event to collect data to assess the extent of the condition 
and to provide recommended performance improvements for existing and 
newly interconnecting solar PV IBRs connected to the Bulk-Power 
System.\43\ NERC issued its second alert in 2018 after the Canyon 2 
Fire event to recommend performance improvements including eliminating 
momentary cessation for registered IBRs already in operation.\44\
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    \42\ NERC uses level 2 alerts to recommend specific actions to 
be taken by registered entities (i.e., ``Recommendation to 
Industry''). A response from recipients, as defined in the alert, is 
required. NERC, About Alerts (2022), https://www.nerc.com/pa/rrm/bpsa/Pages/About-Alerts.aspx. NERC also uses level 1 alerts (i.e., 
``Industry Advisory'') to advise registered entities of issues or 
potential problems, which does not require a response. In addition, 
NERC uses level 3 alerts (i.e., ``Essential Action'') to identify 
actions that registered entities are required to take because they 
are deemed to be ``essential'' to reliability.
    \43\ Loss of Solar Resources Alert I at 4-6 (noting that 
although the alert pertains directly to registered IBRs, the ``same 
potential susceptibility to frequency and voltage perturbations 
during transmission faults exist for all utility grade, and perhaps 
some larger commercial grade solar installations, regardless of the 
interconnection voltage.'').
    \44\ Loss of Solar Resources Alert II at 1-5 (finding again that 
``[a]lthough this NERC Alert pertains specifically to [bulk electric 
system] solar PV resources, the same characteristics may exist for 
non-[bulk electric system] solar PV resources connected to the 
[Bulk-Power System] regardless of installed generating capacity or 
interconnection voltage.'' (footnote omitted)).
---------------------------------------------------------------------------

    19. NERC formed the IRPTF in response to the findings and 
recommendations of the Blue Cut Fire Event Report in order to explore 
the performance characteristics of Bulk-Power System connected IBRs. 
The IRPTF is composed of subject matter experts and representatives 
from a variety of companies, registered entities, and trades groups 
familiar with IBR issues and reliability risks. Among other activities, 
the IRPTF has developed a variety of whitepapers and reliability 
guidelines.\45\ For example, the Modeling and Studies Report documented 
the failure of industry to mitigate IBR-related momentary cessation, 
tripping, and modeling issues.\46\ In March 2020, the IRPTF issued a 
white paper evaluating the applicability of certain Reliability 
Standards to IBRs and identifying seven Reliability Standards with 
potential gaps or areas for improvement.\47\
---------------------------------------------------------------------------

    \45\ See NERC, Reliability Guidelines, Security Guidelines, 
Technical Reference Documents, and White Papers, (2022), https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx 
(providing links to all IRPTF resources).
    \46\ Modeling and Studies Report at iv-v, 1-8.
    \47\ Specifically, the white paper identified Reliability 
Standards: (1) FAC-001-3; (2) FAC-002-2; (3) MOD-026-1; (4) MOD-027-
1; (5) PRC-002-2; (6) TPL-001-4/-5; and (7) VAR-002-4.1. NERC, IRPTF 
Review of NERC Reliability Standards White Paper, 1, (Mar. 2020), 
https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf 
(Reliability Standards Review White Paper).
---------------------------------------------------------------------------

    20. NERC formed the SPIDERWG to, among other things, identify 
potential gaps in the Reliability Standards and address IBR-DER 
modeling and performance.\48\ For example, on December 30, 2019, the 
SPIDERWG submitted a standard authorization request proposing to 
address gaps in Reliability Standard MOD-032-1 (Data for Power System 
Modeling and Analysis) requirements for data collection for the 
purposes of modeling and interconnection-wide planning case models.\49\ 
Based on the extensive record created by the IRPTF and SPIDERWG on the 
need for the Reliability Standards to address IBR impacts on the 
reliable operation of the Bulk-Power System, NERC initiated several 
standards projects \50\ to consider discrete changes

[[Page 74547]]

to the Facilities Design, Connections and Maintenance (FAC), Modeling, 
Data and Analysis (MOD), Protection and Control (PRC), Transmission 
Planning (TPL), and Voltage and Reactive Control (VAR) Reliability 
Standards.\51\
---------------------------------------------------------------------------

    \48\ NERC, System Planning Impacts from DER Working Group 
(SPIDERWG), (2022) https://www.nerc.com/comm/RSTC/Pages/SPIDERWG.aspx.
    \49\ NERC, Standard Authorization Request, Project 2020-01 
Modifications to MOD-032-1 (Dec. 2021), https://www.nerc.com/pa/Stand/Project202202ModificationstoTPL00151andMOD0321DL/2022-02_MOD-032%20SAR%20SPIDERWG_020122.pdf.
    \50\ See NERC Rules of Procedure, app. 3A (Standard Processes 
Manual) (providing the process for developing, modifying, 
withdrawing, or retiring a Reliability Standard. One of the first 
steps in the process is initiating a standards authorization 
request, which is a form used to document the scope and benefit of a 
proposed standards drafting project).
    \51\ See NERC, Informational Filing of Reliability Standards 
Development Plan 2022-2024, Docket No. RM05-17-000, et al., attach. 
A (Reliability Standards Development Plan 2022-2024), 3-4 (filed 
Nov. 30, 2021) (NERC 2022-2024 Reliability Standards Development 
Plan). However, several of these projects lack IBR-specific 
considerations or reporting requirements (e.g., MOD-026-1, MOD-027-
1, and PRC-002-2), lack requirements to assess IBR aggregate impacts 
(e.g., VAR-002-4.1), or are identified in the Reliability Standards 
development plan as ``low priority.'' See also NERC, IBR Strategy, 
https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf (providing 
a milestone plan of proposed SARs, reliability guidelines, and 
whitepapers).
---------------------------------------------------------------------------

    21. Other NERC technical committees have also met to review 
recommendations of the Odessa Disturbance Report, including 
recommendations for Reliability Standards addressing, among other IBR-
related issues: (1) ride through; (2) performance validation; (3) 
analysis and reporting for abnormal inverter options; (4) monitoring; 
and (5) inverter-specific performance requirements.\52\
---------------------------------------------------------------------------

    \52\ NERC, Odessa Disturbance Follow-up White Paper, 3-8 (Oct. 
2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf (Odessa Disturbance 
White Paper).
---------------------------------------------------------------------------

    22. Concurrently with this NOPR, we are also approving revisions to 
Reliability Standards FAC-001-3 (Facility Interconnection Requirements) 
and FAC-002-3 (Facility Interconnection Studies).\53\ The revisions 
were responsive to IRPTF recommendations to modify the standards to: 
(1) clarify the registered entity responsible for determining which 
facility changes require study (a ``qualified change''); and (2) 
clarify that a generator owner should notify affected registered 
entities before making a qualified change. As a part of its petition, 
NERC included examples of qualified changes specific to IBRs, such as a 
change in inverter settings that may result in a difference in 
frequency or voltage support.\54\
---------------------------------------------------------------------------

    \53\ See North American Electric Reliability Corporation, 181 
FERC ] 61,126 (2022).
    \54\ NERC, Petition for Approval of Proposed Reliability 
Standards FAC-001-4 and FAC-002-4, Docket No. RD22-5-000, at 9-13 
(filed June 14, 2022) (including examples of IBR-related qualified 
changes: (1) a change of 10% or more in nameplate capacity of the 
IBR; and (2) a change in the IBR's control settings that cause a 
difference in (a) frequency or voltage support or (b) when the IBR 
stops injecting power into the transmission system).
---------------------------------------------------------------------------

    23. In addition to NERC's efforts, there are voluntary industry 
standards and manufacturer certification efforts related to IBRs in 
place or underway, such as the Institute of Electrical and Electronics 
Engineers (IEEE) standard 2800-2020 \55\ for transmission connected 
IBRs, and IEEE 1547-2018 \56\ and Underwriters Laboratory (UL) standard 
UL 1741 \57\ for IBR-DERs. These efforts may enhance the operating 
performance and control capabilities of IBRs; however, these efforts 
remain at relatively early stages, do not apply to all relevant IBRs, 
and require adoption by state or other regulatory authorities.\58\ The 
proposed directives to NERC to develop new or modify existing 
Reliability Standards are intended to complement existing voluntary 
efforts underway and are not intended to supersede or interfere with 
these efforts.
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    \55\ IEEE Standard for Interconnection and Interoperability of 
Inverter-Based Resources (IBR) Interconnecting with Associated 
Transmission Electric Power Systems (IEEE 2800-2022), https://standards.ieee.org/ieee/2800/10453/ (explaining that 2800-2020 
standard establishes ``[u]niform technical minimum requirements for 
the interconnection, capability, and lifetime performance of [IBRs] 
interconnecting with transmission and sub-transmission systems . . . 
[and includes] . . . performance requirements for reliable 
integration of [IBRs] into the [B]ulk [P]ower [S]ystem.'').
    \56\ IEEE, Interconnection and Interoperability of Distributed 
Energy Resources with Associated Electric Power Systems Interfaces 
(IEEE 1547-2018), https://sagroups.ieee.org/scc21/standards/1547rev/
. The IEEE 1547-2018 and more recent 2020 amendment of this standard 
enhance operating performance and control capabilities of IBR-DER. 
For example, future IBR-DER will be equipped with the capability to 
ride through voltage and frequency fluctuation in support of the 
reliable operation of Bulk-Power System.
    \57\ UL Standard 1741 Edition 3, Inverters, Converters, 
Controllers and Interconnection System Equipment for Use With 
Distributed Energy Resources Scope, https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673.
    \58\ While the IEEE-2800-2020 was approved in September 2022, it 
has yet to be adopted by any transmission entity. For IEEE-1547, 
states have made varied progress in adopting the IBR-DER. Adoption 
of IEEE Standard 1547TM-2018. Further, IEEE 1547-2018 
inverter products are not expected to be generally available to the 
market until April 2023. IEEE, IEEE Standard for Interconnection and 
Interoperability of Distributed Energy Resources with Associated 
Electric Power Systems Interfaces, https://sagroups.ieee.org/scc21/standards/1547rev/.
---------------------------------------------------------------------------

III. The Need for Reform

A. Recent Events Show IBR-Related Adverse Reliability Impacts on the 
Bulk-Power System

    24. A number of events have demonstrated the challenges to 
transmission planning and operations of the Bulk-Power System posed by 
gaps in the Reliability Standards specific to IBRs in the areas of: (1) 
IBR data sharing; (2) IBR model validation; (3) IBR planning and 
operational studies; and (4) registered IBR performance requirements.
    25. The first documented large-scale disturbance event related to 
IBRs occurred in August of 2016 during the Blue Cut Fire event in 
California. Until this event, the potential for IBRs to affect the 
reliability of the Bulk-Power System by tripping or momentarily ceasing 
during faults was unknown.\59\ A NERC/WECC joint task force determined 
that a single 500 kV line-to-line fault caused the widespread loss of 
1,200 MW of primarily solar PV IBRs, which adversely affected the 
balance of generation and load needed to maintain Interconnection 
frequency near a nominal value of 60 Hz.\60\ The task force found that 
the solar PV generation loss was primarily due to the unexpected 
tripping and unanticipated momentary cessation of IBRs.\61\ The report 
indicated that planning studies incorrectly predicted that IBRs would 
ride through the disturbance and would provide power during the event. 
Once aware of the potential for IBRs to trip or enter momentary 
cessation in response to faults, Southern California Edison (SoCal 
Edison) and the California Independent System Operator Corporation 
(CAISO) reviewed the supervisory control and data acquisition (SCADA) 
data from SoCal Edison energy management system and discovered that 
this was not an isolated incident.\62\
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    \59\ Blue Cut Fire Event Report at 15-16.
    \60\ Id. at 1.
    \61\ Id. at 9 (identifying momentary cessation as a major cause 
for the loss of IBRs when voltages rose above 1.1 per unit or 
decreased below 0.9 per unit. NERC also identified IBRs that tripped 
due to erroneous frequency calculations and concluded that a more 
accurate representation of the system frequency measurement should 
be used for inverter controls, and a minimum delay for frequency 
detection and/or filtering should be implemented. NERC reported that 
the Blue Cut fire IBR erroneous frequency calculation issue was 
successfully mitigated).
    \62\ SoCal Edison/CAISO identified seven other instances of 
solar PV IBRs either tripping or entering momentary cessation. Id. 
at 3. See also Modeling and Studies Report at 3-4 (explaining that 
SoCal Edison and CAISO attempted to collect updated generation 
dynamic models from generator owners and discussing their challenges 
in obtaining the data).
---------------------------------------------------------------------------

    26. Despite NERC's efforts to date, events involving registered 
IBRs, unregistered IBRs, and IBR-DERs have continued to occur in areas 
of the country with large penetrations of IBRs.\63\ Noting the 
continuing need to address IBR concerns, the NERC Board of Trustees has 
stated that ``the risk of unreliable performance from [Bulk-

[[Page 74548]]

Power System]-connected inverter-based resources remains high'' and 
that NERC and the Regional Entities ``remain[] concerned with [Bulk-
Power System] performance, modeling, planning and study approaches, and 
is urging immediate industry action.'' \64\ As the resource mix trends 
towards higher penetrations of IBRs, the need to reliably integrate 
these resources into the Bulk-Power System is expected to grow.\65\ 
Although groups such as IEEE and entities like CAISO have attempted to 
address these issues at the state, local, or individual entity level, 
the continuing events across the Bulk-Power System and the risks that 
they pose to its reliable operation underscore the need for mandatory 
Reliability Standards to address these issues on a nationwide basis.
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    \63\ Since the first Blue Cut Fire event in August 2016, there 
have been at least 11 additional events throughout the last six 
years, including the most recently reported event in March 2022. 
NERC, Major Event Analysis Reports, https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx, see supra note 12 (listing the IBR-
related events).
    \64\ NERC, Members Representatives Committee Agenda Package, 2 
(May 2022), https://www.nerc.com/gov/bot/Agenda%20highlights%20and%20Mintues%202013/Policy-Input-Package-May-2022-PUBLIC-POSTING.pdf.
    \65\ See Reliability Standards Review White Paper at 1 (finding 
that the ``electric industry is still experiencing unprecedented 
growth in the use of inverters as part of the bulk power system and 
growth is possibly creating new circumstances where current 
standards may not be sufficiently addressing those needs.'').
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B. Reliability Standards Do Not Adequately Address IBR Reliability 
Risks

1. Data Sharing
    27. The Reliability Standards do not ensure that planning 
coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities receive accurate and 
complete data on the location, capacity, telemetry, steady-state, 
dynamic and short circuit modeling information, control settings, ramp 
rates, equipment status, disturbance analysis data, and other 
information about IBRs (collectively, IBR data). IBR data is necessary 
to properly plan, operate, and analyze performance on the Bulk-Power 
System.\66\ As evidenced by the Modeling and Studies Report, the 
Reliability Standards do not ensure that IBR generator owners and 
operators consistently share IBR data, as at least a portion of the 
information that is shared is inaccurate or incomplete.\67\ For 
example, in the Modeling and Studies Report, the IRPTF found that 
Reliability Standard MOD-032-1 ``does not prescribe the details that 
the modeling requirements must cover; rather, the standard requirements 
leave the level of detail and data formats up to each TP [transmission 
planner] and PC [planning coordinator] to define.'' Further, the IRPTF 
found that many of the dynamic models submitted in response to an IBR-
related NERC Alert ``that were intended to represent the existing 
settings and controls currently installed in the field either did not 
match the data provided by the [generator owner] for actual settings or 
did not meet the [transmission planner and planning coordinator] 
requirements for model performance, (i.e., incorrect models used, 
incorrect parameters, or inability of model to initialize).'' \68\
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    \66\ Loss of Solar Resources Alert II at 7-8 (describing 
examples of planning and operational IBR data) and Odessa 
Disturbance Report at 20-21; see generally WI Base Case IBR Review, 
NERC, Reliability Guideline: DER Data Collection for Modeling in 
Transmission Planning Studies, (Sept. 2020) (IBR-DER Data Collection 
Guideline).
    \67\ See Modeling and Studies Report at 33 (finding that a 
``significant number of inverter-based resources, particularly solar 
PV resources, have submitted [root-mean-square] positive sequence 
dynamic models for the interconnection-wide case creation process 
(i.e., MOD-032-1) that do not accurately represent the control 
settings programmed into the inverters installed in the field.''). 
See also Western Interconnection (WI) Base Case IBR Review at 27 
(describing comments from transmission planners and planning 
coordinators relaying concerns regarding generator owners' lack of 
timely responses (or any response in many cases) regarding modeling-
related issues on the use of generic manufacturer-supplied data, and 
failure to update models consistent with Reliability Standard MOD-
032-1).
    \68\ Modeling and Studies Report at 33.
---------------------------------------------------------------------------

    28. Without accurate and complete IBR data, planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities are not able to develop accurate 
system models that account for the behavior of IBRs on their system, 
nor are they able to facilitate the analysis of Bulk-Power System 
disturbances.\69\
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    \69\ E.g., Commission Staff, Distributed Energy Resources 
Technical Considerations for the Bulk Power System Staff Report, 
Docket No. AD18-10-000 (filed Feb. 15, 2018) (Commission Staff IBR-
DER Reliability Report); Modeling and Studies Report at 33 
(recommending that generator owners, for both registered and 
unregistered IBRs, ``should submit updated models to the 
[transmission planners and planning coordinators] as quickly as 
possible to accurately reflect the large disturbance behavior of 
[Bulk-Power System]-connected solar PV resources in the 
interconnection-wide base cases used for planning assessments.'').
---------------------------------------------------------------------------

a. Registered IBR Data Sharing
    29. The Reliability Standards do not ensure that transmission 
planners and operators receive modeling data and parameters from all 
bulk electric system generation resources necessary to create and 
maintain valid individual registered IBR models used to perform steady-
state, dynamic, and short circuit studies. While Reliability Standard 
MOD-032-1(Data for Power System Modeling and Analysis), Requirement R2, 
requires generator owners to submit modeling data and parameters to 
their transmission planners and planning coordinators, it does not 
require generator owners to submit registered IBR-specific modeling 
data and parameters, such as control settings for momentary cessation 
and ramp rates, necessary for modeling steady state and dynamic 
registered IBR performance for purposes of planning the Bulk-Power 
System.\70\ Similarly, Reliability Standard TOP-003-4 (Operational 
Reliability Data) does not require generator owners to submit 
registered IBR-specific modeling data and parameters transmission 
operators or balancing authorities, such as control settings for 
momentary cessation and ramp rates, necessary for modeling steady state 
and dynamic registered IBR performance for purposes of operating the 
Bulk-Power System.
---------------------------------------------------------------------------

    \70\ See Modeling and Studies Report at 35 (stating that 
Reliability Standard MOD-032-1 ``does not prescribe the details that 
the modeling requirements must cover; rather, the standard 
requirements leave the level of detail and data formats up to each 
[transmission planner] and [planning coordinator] to define.'' 
(footnote omitted)).
---------------------------------------------------------------------------

b. Unregistered IBR and IBR-DER Data Sharing
    30. The Reliability Standards do not ensure that transmission 
planners and operators receive modeling data and parameters regarding 
unregistered IBRs and IBR-DERs that, individually or in the aggregate, 
are capable of adversely affecting the reliable operation of the Bulk-
Power System. As shown by various reports and guidelines,\71\ planners 
and operators do not currently have the data to accurately model the 
behavior of unregistered IBRs as well as IBR-DERs in the aggregate for 
steady-state, dynamic, and short circuit studies.
---------------------------------------------------------------------------

    \71\ See, e.g., Commission Staff IBR-DER Reliability Report at 
11-13 (explaining that absent adequate data, many Bulk-Power System 
models and operating tools will not fully represent the effects of 
IBR-DERs in aggregate. The report also noted the lack of a formal 
process to provide static IBR-DER data to Bulk-Power System 
operators and planners as well as the limited visibility that 
operators and planners have into IBR-DER telemetry data); see also 
IBR-DER Data Collection Guideline at 2 (recommending that 
transmission planners and planning coordinators update their data 
reporting requirements for Reliability Standard MOD-032-1, 
Requirement R1 to explicitly describe the requirements for aggregate 
IBR-DER data in a manner that is clear and consistent with their 
modeling practices. The guideline also recommended that transmission 
planners and planning coordinators establish modeling data 
requirements for steady-state IBR-DERs in aggregate and coordinate 
with their distribution providers to develop these requirements).
---------------------------------------------------------------------------

c. Disturbance Monitoring Data Sharing
    31. The Reliability Standards do not ensure that transmission 
planners and operators receive disturbance

[[Page 74549]]

monitoring data regarding all generation resources capable of having a 
material impact on the reliable operation of the Bulk-Power System, 
including IBRs, to adequately assess disturbance events (e.g., a fault 
on the line, a generator tripped off-line) and their behavior during 
those events. Without adequate monitoring capability, the disturbance 
analysis data for a system event is not comprehensive enough to 
effectively determine the causes of the system event.\72\ Further, the 
absence of adequate monitoring capability leads to the potential for 
unreliable operation of resources due to the inability to effectively 
gather disturbance analysis data and develop mitigation strategies for 
abnormal resource performance during disturbance events.
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    \72\ 2021 Solar PV Disturbances Report at 13. The report 
explains that the ``analysis team had significant difficulty 
gathering useful information for root cause analysis at multiple 
facilities . . . [and] this led to an abnormally large number of 
`unknown' causes of power reduction for the plants analyzed.''
---------------------------------------------------------------------------

    32. Limitations on the availability of event data have hampered 
efforts by NERC and industry to determine the causes of various events 
since 2016, explained in more detail below. In many instances, data was 
limited and disturbance monitoring equipment was absent because 
registered IBRs generally do not fall within the thresholds of the 
current Reliability Standard PRC-002-2 (Disturbance Monitoring and 
Reporting Requirements) Attachment 1 methodology requirements for 
equipment installation given that they often interconnect at lower 
voltages and are typically smaller compared to synchronous 
generators.\73\ While Reliability Standard PRC-002-2 requires the 
installation of disturbance monitoring equipment at certain key nodes 
(e.g., stability limited interfaces), and such limited placements were 
adequate to provide the data necessary to analyze major system events 
in the past, they are not sufficient to analyze the distributed system 
events that have become more common since 2016.\74\
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    \73\ Reliability Standard PRC-002-2, Attachment 1 includes a 
methodology for selecting which buses require sequence of events 
recording and fault recording data--IBRs do not meet the threshold 
for this methodology.
    \74\ See, e.g., Angeles Forest and Palmdale Roost Events Report 
at 23 (explaining that the lack of data visibility and poor data 
quality continue to be a concern for comprehensive event analysis 
after large Bulk-Power System disturbances, as well as how the 
quality of event reporting is negatively affected by data 
acquisition resolution issues as a lack of high speed data captured 
at the IBR controller hinders a complete analysis of IBR behavior in 
response to Bulk-Power System fault events); San Fernando 
Disturbance Report at 7 (explaining that many facilities have data 
archiving systems that only record, store, and retrieve information 
with a one-minute resolution (or a five-minute resolution in some 
cases) and that no facilities recorded electrical quantities with 
sufficient resolution to observe their on-fault behavior, limiting 
the ability to perform a more detailed analysis of the event.); 
Odessa Disturbance Report at 11 (indicating some improved monitoring 
data, but noting the monitoring capability at solar PV facilities is 
not comprehensive enough to effectively perform root cause analysis 
and is leading to unreliable operation of these resources due to the 
inability to effectively develop mitigations for abnormal 
performance). See generally Odessa Disturbance White Paper; NERC, 
San Fernando Disturbance Follow-Up NERC Inverter-Based Resource 
Performance Working Group White Paper, (June 2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20(003).pdf (San 
Fernando Disturbance White Paper).
---------------------------------------------------------------------------

2. IBR and IBR-DER Data and Model Validation
    33. IBR-specific modeling data and parameters are necessary to 
ensure that the registered entities responsible for planning and 
operating the Bulk-Power System can validate both the individual 
registered IBR and unregistered IBR data as well as IBR-DER data in the 
aggregate by comparing the provided data and resulting models with 
actual performance and behavior.\75\ Therefore, even if the Reliability 
Standards did ensure planning coordinators, transmission planners, 
reliability coordinators, transmission operators, and balancing 
authorities receive registered IBR modeling data from registered IBR 
generator owners and operators, the Reliability Standards would still 
need to include unregistered IBR modeling data and parameters and IBR-
DER aggregate modeling data and parameters to ensure reliability. The 
bulk electric system definition, which delineates the entities required 
to comply with the Reliability Standards, does not include unregistered 
IBRs or IBR-DERs. Therefore, the current Reliability Standards do not 
address the provision of either unregistered IBR or IBR-DER aggregate 
modeling data and parameters. Further, the Reliability Standards do not 
include IBR-specific modeling data and parameters (e.g., performance 
and control settings). As a result, the planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities need to coordinate with: (1) 
registered IBR generator owners and operators, (2) transmission owners 
that have unregistered IBRs connected to their systems, (3) and the 
distribution providers that have IBR-DERs to obtain IBR specific 
modeling data and parameters so that the transmission planners and 
operators can validate the accuracy of such data to create meaningful 
models of steady-state and dynamic registered IBR, unregistered IBR, 
and aggregate IBR-DER performance.\76\
---------------------------------------------------------------------------

    \75\ Modeling and Studies Report at 37 (recommending revising 
Reliability Standards MOD-026-1 (Verification of Models and Data for 
Generator Excitation Control System or Plant Volt/Var Control 
Functions) and MOD-027-1 (Verification of Models and Data for 
Turbine/Governor and Load Control or Active Power/Frequency Control 
Functions) to ``ensure that large disturbance behavior of [IBRs] is 
verified.''). In addition, the task force recommended that 
transmission planners and planning coordinators ``should be required 
to verify the appropriateness of all dynamic model parameters to 
ensure suitability of these parameters to match actual performance 
for all operating conditions.'' Id. See also WI Base Case IBR Review 
at v (recommending that IBR owners ensure that all data fields are 
reported correctly, that transmission planners and planning 
coordinators ``should verify that the data fields are submitted 
correctly,'' and that the Regional Entity ``should ensure that data 
quality checks are being performed on all incoming data from 
[transmission planners] and [planning coordinators] for their 
areas.'').
    \76\ Static or steady-state models represent electrical 
component state variables as constant with respect to the time 
variable of the simulation. Steady-state models are used to 
represent a single snapshot of balanced system conditions as 
observed during normal Bulk-Power System operations and serve as a 
basis of subsequent time-variant technical studies. Dynamic models 
represent electrical component state variables that vary with time 
depending on the course of the simulation. Dynamic models are built 
upon steady-state models and may be validated to ensure they 
adequately reflect actual historic performance and/or field-testing 
data. Dynamic models are used by the industry to evaluate resource 
(i.e., generation and load) performance during simulated events and 
event investigations.
---------------------------------------------------------------------------

    34. System planners and operators need accurate planning, 
operational, and interconnection-wide models to ensure reliable 
operation of the system. Planners and operators use electrical 
component models to build the generation, transmission, and 
distribution facility models that form the planning and operational 
area models, and these area models are combined with the models of 
their neighboring footprints to form the interconnection-wide models. 
Each of the planning, operational, and interconnection-wide models 
consist separately of steady state, dynamic, and short circuit models.
    35. Without planning, operational, and interconnection-wide models 
that accurately reflect the resource (e.g., generators and loads) 
behavior in steady state and dynamic conditions; otherwise, planners 
and operators are unable to adequately predict resources' behaviors, 
including momentary cessation from both individual and aggregate 
registered IBRs and unregistered IBRs, as well as IBR-DERs in the 
aggregate and subsequent impacts

[[Page 74550]]

on the Bulk-Power System.\77\ Accordingly, to be able to adequately 
predict resources' behaviors, planners and operators must validate and 
update resource models by comparing the provided data and resulting 
models against actual operational behavior.\78\ When accuracy and 
validation of models are combined, these planning, operational, and 
interconnection-wide models enable planners and operators to perform 
valid planning, operational, and interconnection-wide studies.
---------------------------------------------------------------------------

    \77\ See IBR Interconnection Requirements Guideline at 24 
(stating that a systemic modeling issue was uncovered regarding the 
accuracy of the inverter-based resource dynamic models submitted in 
the interconnection-wide base cases following the issuance of the 
NERC Alert related to the Canyon 2 Fire disturbance).
    \78\ See Modeling and Studies Report at 35 (explaining that 
assessments on the accuracy or reasonableness of modeling parameter 
values are not typically performed and standardized validity testing 
for dynamic models of newer generation inverter-based resources is 
not readily available to planners; therefore, contributing to 
inaccuracies in the interconnection-wide base cases).
---------------------------------------------------------------------------

a. Approved Component Models
    36. The starting points for an accurate planning, operational, and 
interconnection-wide model are the steady state, dynamic, and short 
circuit models of the elements that make up generation, transmission, 
and distribution facilities. To this end, NERC has worked with its 
stakeholders to develop, validate, and maintain a library of 
standardized approved component models (e.g., generator elements) and 
parameters for powerflow and dynamic cases.\79\ NERC's approved 
component model list is a collection of generic industry steady-state 
and dynamic models (e.g., excitor, governor, load, etc.) that when 
combined accurately reflect the steady-state and dynamic performance of 
a resource.\80\ Despite these efforts, some resource owners still 
provide modeling data that is based on a proprietary model rather than 
an approved industry-vetted model.\81\ The use of proprietary models in 
interconnection-wide models can be problematic because their internal 
model components cannot be viewed or modified, and thus produce outputs 
that cannot be explained or verified.\82\ Without using approved 
generator models that accurately reflect the generator behavior in 
steady state and dynamic conditions, planners and operators are unable 
to adequately predict IBR behavior and subsequent impact on the Bulk-
Power System.\83\ The Reliability Standards do not require the use of 
NERC's approved component models; instead, models are referred to 
generally in Reliability Standard MOD-032-1 Attachment 1.\84\
---------------------------------------------------------------------------

    \79\ NERC Libraries of Standardized Powerflow Parameters and 
Standardized Dynamics Models version 1 (Oct. 2015), https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf (NERC 
Standardized Powerflow Parameters and Dynamics Models).
    \80\ The models are specific to the power flow software. NERC 
communicates the approved models list by issuing modeling 
notifications and guidelines. NERC annually assesses the 
interconnection-wide case quality and publishes a report to help 
entities responsible for complying with Reliability Standard MOD-
032-1 to resolve model issues and improve the cases. See NERC, 
Reliability Assessment and Performance Analysis Department Modeling 
Assessments, https://www.nerc.com/pa/RAPA/ModelAssessment/Pages/default.aspx.
    \81\ NERC Standardized Powerflow Parameters and Dynamics Models 
at 1 (explaining that ``[s]ome of the model structures have 
information that is considered to be proprietary or confidential, 
which impedes the free flow of information necessary for 
interconnection[hyphen]wide power system analysis and model 
validation.'') See also NERC, Events Analysis Modeling Notification 
Recommended Practices for Modeling Momentary Cessation Initial 
Distribution, n.4 (Feb. 2018), https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf (explaining that more 
detailed vendor-specific models may be used for local planning 
studies; however, they are generally not allowed or recommended for 
the interconnection-wide cases).
    \82\ See, e.g., Electric Power Research Institute, Model User 
Guide for Generic Renewable Energy System, 2 (June 2015), https://www.epri.com/research/products/000000003002006525 (explaining that 
the ``models presented here were developed primarily for the purpose 
of general public use and benefit and to eliminate the long standing 
issues around many vendor-specific models being proprietary and thus 
neither publicly available nor easily disseminated among the many 
stakeholders. Furthermore, using multiple user-defined non-standard 
models within large interconnection studies, in many cases, 
presented huge challenges and problems with effectively and 
efficiently running the simulations.'').
    \83\ NERC Standardized Powerflow Parameters and Dynamics Models 
(explaining that there is a growing need for accurate 
interconnection[hyphen]wide powerflow and dynamics simulations that 
analyze phenomena such as: frequency response, inter-area 
oscillations, and interactions between the growing numbers of wide-
area control and protections systems).
    \84\ Reliability Standard MOD-032-1, Attachment 1 (explaining 
that if a user-written model(s) is submitted in place of a generic 
or library model, it must include the characteristics of the model, 
including block diagrams, values and names for all model parameters, 
and a list of all state variables).
---------------------------------------------------------------------------

b. IBR Plant Dynamic Model Performance Verification
    37. Once each generator provides a NERC and industry-approved 
generator model, the model performance must be verified by real-world 
data.\85\ The currently effective Reliability Standards MOD-026-1 \86\ 
and MOD-027-1 \87\ require the generator owner to verify models and 
data for specific components of synchronous resources (e.g., generator 
excitation control systems, plant volt/var control functions, turbine/
governor and load controls, and active power/frequency controls), but 
they do not require a generator owner to provide verified models and 
data for IBR-specific controls (e.g., power plant central controller 
functions and protection system settings). Further, the Reliability 
Standards neither require verified dynamic models from the transmission 
owner for unregistered IBRs nor require verified IBR-DER dynamic models 
in the aggregate from distribution providers.
---------------------------------------------------------------------------

    \85\ NERC Standardized Powerflow Parameters and Dynamics Models 
at 1 (explaining that the NERC Modeling Working Group was tasked to 
develop, validate, and maintain a library of standardized component 
models and parameters for powerflow and dynamics cases. The 
standardized models in these libraries have documentation describing 
their model structure, parameters, and operation. This information 
has been vetted by the industry and thus deemed appropriate for 
widespread use in interconnection[hyphen]wide analysis.).
    \86\ Reliability Standard MOD-026-1 (Verification of Models and 
Data for Generator Excitation Control System or Plant Volt/Var 
Control Functions).
    \87\ Reliability Standard MOD-027-1 (Verification of Models and 
Data for Turbine/Governor and Load Control or Active Power/Frequency 
Control Functions).
---------------------------------------------------------------------------

    38. Transmission planners and operators need dynamic models (i.e., 
models of equipment that reflect the equipment's behavior during 
changing grid conditions and disturbances) that accurately represent 
the dynamic performance of all generation resources, including 
momentary cessation when applicable. As discussed in several NERC 
analyses,\88\ current IBR dynamic models do not accurately represent 
disturbance behavior due to model deficiencies and because certain key 
parameters that govern large disturbance response are incorrect; thus, 
planners are not able to rely on these IBR dynamic models. Unless IBR 
models are verified to ensure that the models accurately reflect IBR 
performance during testing or actual events, planners' and system 
operators' unverified models may indicate that the IBRs will behave 
reliably when studied in planning and operational analyses, even if 
ride through operation modes such as momentary cessation persist in 
actual operations, as observed during

[[Page 74551]]

the Blue Cut Fire and Canyon 2 Fire events. Additionally, the 2017 NERC 
DER Report explained that accurate IBR-DER dynamic models are needed 
where ``[IBR-]DERs are expected to have a significant impact on the 
modeling results.'' \89\
---------------------------------------------------------------------------

    \88\ WI Base Case IBR Review at 18, 25 (finding that the models 
are not parameterized with as-built settings and that verification 
of dynamic models is not capturing errors); see also Modeling and 
Studies Report at 34 (finding that a significant number of generator 
owners submitted data in response to the Loss of Solar Resources 
Alert II ``indicating that they could eliminate the use of 
[momentary cessation] for existing resources; however, either no 
model of proposed changes was provided, or the provided model did 
not meet [transmission planner] and [planning coordinator] 
requirements for model performance.'').
    \89\ NERC, Distributed Energy Resources: Connection Modeling and 
Reliability Considerations, 7 (Feb. 2017), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf (NERC DER Report) at 6 
(explaining that ``[a]n assessment of the expected impact will have 
to be scenario-based, and the time horizon of interest may vary 
between study types. For long-term planning studies, expected DER 
deployment levels looking 5-10 years ahead may reasonably be 
considered.''). The NERC DER Report also noted that modeling the 
modern Bulk-Power System ``with a detailed representation of a large 
number of [IBR-]DER[s] and distribution feeders can increase the 
complexity, dimension, and handling of the system models beyond 
practical limits in terms of computational time, operability, and 
data availability.'' Id.
---------------------------------------------------------------------------

    39. NERC has issued multiple recommendations for: (1) generator 
owners of IBRs to ensure that their dynamic models accurately represent 
the behavior of the actual installed equipment; \90\ (2) transmission 
planners and planning coordinators to work with generator owners and 
operators of IBRs connected to their system to ensure that the dynamic 
models correctly represent the large disturbance behavior of the actual 
installed equipment; \91\ and (3) transmission planners and planning 
coordinators to develop updated dynamic models of their systems that 
accurately represent momentary cessation and to study the impacts of 
IBRs on the Bulk-Power System.\92\
---------------------------------------------------------------------------

    \90\ See, e.g., Loss of Solar Resources Alert II at 2 
(generators should ``[e]nsure that the dynamic model(s) being used 
accurately represent the dynamic performance of the solar 
facilities.'' The generator owners should ``update the dynamic 
model(s) to accurately represent momentary cessation and provide the 
model(s) to the Transmission Planner and Planning Coordinator (to 
support . . . Reliability Standard TPL-001-4 studies) and to the 
Reliability Coordinator, Transmission Operator, and Balancing 
Authority (in accordance with . . . Reliability Standards TOP-003-3 
and IRO-010-2).''); see also WI Base Case IBR Review at 18, 25 
(recommending that the IBR generator owners update their generic 
models as soon as possible).
    \91\ See, e.g., Modeling and Studies Report at 33 (recommending 
that ``[Generator owners] should submit updated models to the 
[transmission planners] and [planning coordinators] as quickly as 
possible to accurately reflect the large disturbance behavior of 
[Bulk-Power System]-connected solar PV resources in the 
interconnection-wide base cases used for planning assessments. This 
applies to [bulk electric system] resources as well as non-[bulk 
electric system] resources connected to the [Bulk-Power System].''). 
NERC further recommended that ``[transmission planners] and 
[planning coordinators] should proactively work with all [Bulk-Power 
System]-connected solar PV resources connected to their system to 
ensure that the dynamic models correctly represent the large 
disturbance behavior of the actual installed equipment. [Generator 
owners] should verify the dynamic model parameters with actual 
equipment and control settings. These activities should occur on a 
regular basis.'' Id.
    \92\ Id. at 34; see also Loss of Solar Resources Alert II at 3.
---------------------------------------------------------------------------

c. Validating and Updating System Models
    40. Transmission planners and operators must validate and update 
system models by comparing the provided data and resulting system 
models against actual system operational behavior. While Reliability 
Standard MOD-033-2 requires data validation of the interconnection-wide 
system model,\93\ the Reliability Standards lack clarity as to whether 
models of registered IBRs, unregistered IBRs, and IBR-DERs in the 
aggregate are required to represent the real-world behavior of the 
equipment installed in the field for interconnection-wide disturbances 
that have demonstrated common mode failures of IBRs.\94\
---------------------------------------------------------------------------

    \93\ Reliability Standard MOD-033-2 (Steady State and Dynamic 
System Model Validation), Requirements R1, R2.
    \94\ NERC annually assesses the interconnection-wide case 
quality and publishes a report to help entities responsible for 
complying with Reliability Standard MOD-032 to resolve model issues 
and improve the cases. As NERC's 2021 Case Quality Metrics 
Assessment asserts, currently planners are neither able to develop 
accurate system models that account for the IBRs on their system, 
nor facilitate the analysis of Bulk-Power System disturbances. See 
NERC, Case Quality Metrics Annual Interconnection-wide Model 
Assessment, (Oct. 2021), https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf.
---------------------------------------------------------------------------

    41. In addition, Reliability Standard MOD-032-1 lacks clarity on 
whether generator owners are required to communicate to planners and 
operators if there are any changes to registered IBRs, including 
settings, configurations, and ratings. Additionally, transmission 
owners are not required to communicate to planners and operators if 
there are any changes to unregistered IBRs for modeling, including 
settings, configurations, and ratings. Similarly, distribution 
providers are not required to communicate to planners and operators if 
there are any changes to IBR-DERs in the aggregate for modeling, 
including settings, configurations, and ratings. While Reliability 
Standards MOD-032-1 and MOD-033-2 have iterative updating and 
validation processes, Reliability Standard MOD-032-1 lacks IBR-specific 
modeling data and parameters and Reliability Standard MOD-033-2 does 
not contemplate the technology-specific performance characteristics of 
registered IBRs, unregistered IBRs, and IBR-DERs. As NERC explained in 
its petition for approval of the proposed Reliability Standards MOD-
032-1 and MOD-033-2, the lack of generator model verification can 
result in ``the use of inaccurate models [that] could result in grid 
underinvestment, unsafe operating conditions, and ultimately widespread 
power outages.'' \95\
---------------------------------------------------------------------------

    \95\ NERC, Petition for Approval of Proposed Reliability 
Standards MOD-032-1 and MOD-033-1, Docket No. RD14-5-000, at 2, 9-10 
(filed Feb. 25, 2014).
---------------------------------------------------------------------------

    42. In the November 2020 San Fernando Disturbance Report, NERC and 
WECC found that the previously identified modeling issues in the 
interconnection-wide planning base cases and modeling challenges 
continued to be an issue.\96\ The San Fernando Disturbance Report again 
recommended that generator owners and generator operators take steps to 
ensure communication of changes to various settings, topologies, and 
ratings to their relevant transmission planner, planning coordinator, 
balancing authority, and reliability coordinator.\97\
---------------------------------------------------------------------------

    \96\ San Fernando Disturbance Report at ix; Odessa Disturbance 
Report at 22-28, 29-31.
    \97\ San Fernando Disturbance Report at ix.
---------------------------------------------------------------------------

d. Lack of Coordination When Creating and Updating Planning, 
Operational, and Interconnection-Wide Models
    43. Planners and operators need to coordinate planning, 
operational, and interconnection-wide models so that they represent all 
generation resources--including registered IBRs, unregistered IBRs, 
IBR-DERs in the aggregate and synchronous generation--and load. When 
coordinated properly, these sets of models ensure enough detail for 
planners and operators to perform valid planning, operational, and 
interconnection-wide studies.
    44. Reliability Standard MOD-032-1 Requirement R4 requires planning 
coordinators to make available models for their planning areas to the 
ERO or its designee \98\ to support creation of interconnection-wide 
cases.\99\ Two reliability gaps lead to interconnection-wide cases that 
do not reflect the large disturbance behavior that NERC identified in 
its analyses of IBR disturbance events. The first gap is the use of 
incorrect and unvalidated registered IBR, unregistered IBR, and IBR-DER 
models (discussed above) that do not accurately represent performance 
and behavior of both individual and

[[Page 74552]]

aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in 
the aggregate. Planners and operators incorporate incorrect and 
unvalidated IBR models within the footprint of the planner and operator 
area models. These registered IBR, unregistered IBR, and IBR-DER model 
inaccuracies from the planning and operation area models then propagate 
into the interconnection-wide cases.
---------------------------------------------------------------------------

    \98\ See Reliability Standard MOD-032-1, Requirement R4.
    \99\ In this NOPR, the terms ``interconnection-wide case'' and 
``interconnection-wide model'' are interchangeable. Both refer to a 
collection of electric power system models and requisite data 
developed to represent either a snapshot of the electric power 
system at a particular point of time (e.g., year, season) or to 
represent the power system at a particular operating condition 
(i.e., normal or abnormal).
---------------------------------------------------------------------------

    45. Secondly, there is a coordination gap among registered entities 
that build and verify interconnection-wide cases. Reliability Standards 
MOD-032-1 and MOD-033-2 do not obligate the applicable entities to work 
collaboratively to create interconnection-wide cases that accurately 
reflect real-world interconnection-wide IBR performance and 
behavior.\100\ In the Western Interconnection, for example, a single 
MOD-032-1 designee, WECC, collects a set of planning models from the 
planning authority and builds an interconnection-wide case on the 
behalf of the registered entities. Having a single MOD-032-1 designee 
helps in efficiently building an interconnection-wide case. However, 
the process does not contain requirements for the MOD-032-1 designee to 
coordinate and verify with MOD-033-2 functional entities (e.g., the 
system operators) that the interconnection-wide cases reflect real-
world IBR behaviors. For example, the Modeling and Studies Report 
indicates that the MOD-032-1 feedback loops are not being used to 
correct modeling issues.\101\ Further, NERC's 2020 annual assessment of 
interconnection-wide case quality report explains that there is a need 
to compare the interconnection-wide models against actual measured 
system conditions and encourages planning coordinators to consider 
performing the comparison during MOD-033 evaluation, but such a 
comparison is not required by a standard.\102\ The Reliability 
Standards should ensure registered entities coordinate to build 
interconnection-wide cases that reflect the large disturbance behavior 
of both individual and aggregate registered IBRs and unregistered IBRs, 
as well as IBR-DERs in the aggregate (i.e., tripping offline or 
momentary cessation individually or in the aggregate in response to a 
single fault on a transmission or sub-transmission system).
---------------------------------------------------------------------------

    \100\ Reliability Standard MOD-032-1 is applicable to the 
following entities: (1) balancing authority, (2) generator owner, 
(3) load serving entity, (4) planning authority/planning 
coordinator, (5) resource planner, (6) transmission owner, (7) 
transmission planner, and (8) transmission service provider.
    \101\ See Modeling and Studies Report at 27 (finding that 
``[t]he feedback loops developed in MOD-032-1 are not being used by 
[transmission planners] and [planning coordinators] to correct 
modeling issues, nor are [transmission planners] and [planning 
coordinators] being proactive to address identified issues on a 
widespread basis.'').
    \102\ NERC, Case Quality Metrics Annual Interconnection-Wide 
Model Assessment, vii (Oct. 2020), https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2020_Case_Quality_Metrics_Assessment-FINAL_postpubs.pdf (explaining that the report focuses solely on the 
case data quality of the individual component models comprising the 
base case and that validation of an interconnection-wide case or 
overall model performance requires comparison of the cases to actual 
measured system conditions and are not included in the report. 
Nevertheless, the report does encourage planning coordinators ``to 
consider these metrics in their MOD-033 evaluation and to also 
include metrics on case fidelity.'').
---------------------------------------------------------------------------

    46. NERC and WECC identified the impacts of these two reliability 
gaps in the WI Base Case IBR Review. Specifically, NERC and WECC found 
that IBR dynamic models used for interconnection-wide planning and 
operating studies do not properly represent the behavior of the 
equipment installed in the field, as current interconnection-wide cases 
contain many inaccurate and unverified IBR models, and many wind and 
solar PV IBRs are not represented.\103\
---------------------------------------------------------------------------

    \103\ WI Base Case IBR Review at 1-4.
---------------------------------------------------------------------------

3. IBR and IBR-DER Planning and Operational Studies
    47. The Reliability Standards do not ensure that planning and 
operational studies assess the performance and behavior (e.g., IBRs 
tripping or entering momentary cessation individually or in the 
aggregate) of both individual and aggregate registered IBRs and 
unregistered IBRs, as well as IBR-DERs in the aggregate. Planning and 
operational studies must use validated registered IBR, unregistered 
IBR, and IBR-DER aggregate modeling and operational data (as discussed 
in above Section III.B.1. Data Sharing and Section III.B.2. IBR and 
IBR-DER Data and Model Validation) to ensure studies account for the 
actual behavior of registered IBRs, unregistered IBRs, and IBR-DERs in 
the aggregate. Planning and operational studies must assess the 
performance and behavior of individual and aggregate registered IBRs 
and unregistered IBRs, as well as IBR-DERs in the aggregate, during 
normal and contingency conditions for the reliable operation of the 
Bulk-Power System.
a. Planning Studies
    48. Transmission planning (TPL) Reliability Standards are intended 
to ensure that the transmission system is planned and designed to meet 
an appropriate and specific set of reliability criteria. The TPL 
Reliability Standards, however, do not require planners to study in 
planning assessments the performance and behavior specific to both 
individual and aggregate registered IBRs and unregistered IBRs, as well 
as IBR-DERs in the aggregate, under normal operations and contingency 
event conditions. This reliability gap in planning assessments may lead 
to false expectations that system performance requirements are met and 
may inadvertently mask potential reliability risks in planning and 
operations. NERC's 2021 Battery Storage and Hybrid Plants Guideline 
further identifies reliability gaps in planning assessments related to 
newer technologies and provides recommendations to address some of the 
aforementioned concerns.\104\ Nevertheless, as reliability guidelines 
are voluntary, the gap remains.
---------------------------------------------------------------------------

    \104\ See BESS Performance Modeling Guideline, ix Recommendation 
S1 and S2 (explaining study process enhancements and expansion of 
study conditions are needed for both interconnection-wide and annual 
planning assessments to ensure that the variability and uncertainty 
of renewable energy resources (e.g., registered IBRs, unregistered 
IBRs, and IBR-DERs in the aggregate) are reflected in planning 
analyses with appropriate dispatch conditions and under stressed 
operating conditions. NERC further explained that renewable energy 
resources have led to different operating conditions than were 
previously used in planning assessments and ``indicates that 
developing suitable and reasonable study assumptions will become a 
significant challenge for future planning analyses.'').
---------------------------------------------------------------------------

    49. Reliability Standard TPL-001-4 (Transmission System Planning 
Performance Requirements) requires planning to ensure reliable 
operations over a broad spectrum of system conditions and following a 
wide range of probable contingencies.\105\ The 2021 Solar PV 
Disturbances Report explains that ``many of the reliability issues 
observed in real-time [e.g., solar PV resources tripping off line and 
momentary cessation] and identified in the numerous disturbance reports 
are not being captured in planning studies.'' \106\ The Odessa 
Disturbance Report explains that IBR plants are ``abnormally responding 
to [Bulk-Power System] disturbance events and ultimately tripping 
themselves off-line'' and that these issues are not being

[[Page 74553]]

properly detected by the models and studies conducted during annual 
planning assessments.\107\ In addition, the Panhandle Report found that 
``many [Bulk-Power System]-connected inverter-based resources (and 
distributed energy resources) will significantly reduce active power 
for depressed voltages'' that will change grid dynamics and should be 
accurately modeled in simulations and studied during planning 
assessments.\108\
---------------------------------------------------------------------------

    \105\ Reliability Standard TPL-001-5.1 (Transmission System 
Planning Performance Requirements) was approved by the Commission to 
become effective on July 1, 2023. See N. Am. Elec. Reliability 
Corp., Docket No. RD20-8-000 (June 10, 2020) (delegated letter 
order) (approving a NERC-proposed erratum to Reliability Standard 
TPL-001-5); Transmission Planning Reliability Standard TPL-001-5, 
Order No. 867, 85 FR 8155 (Feb. 13, 2020), 170 FERC ] 61,030 (2020) 
(approving Reliability Standard TPL-001-5).
    \106\ 2021 Solar PV Disturbances Report at 8 and 21.
    \107\ Odessa Disturbance Report at 43.
    \108\ Panhandle Report at 8.
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    50. The NERC DER Report found that many IBR-DERs are generally not 
visible to Bulk-Power System planners and stated that Bulk-Power System 
plans must account for this lack of visibility.\109\ The report 
recommended that IBR-DERs be ``modeled in an aggregated and/or 
equivalent way to reflect their dynamic characteristics and steady-
state output.'' \110\ The report also found that planners face a 
challenge with respect to forecasting the adoption of IBR-DER types 
over long-term planning horizons with ``sufficient locational 
granularity for identifying and planning needed [Bulk-Power System] 
infrastructure upgrades.'' \111\
---------------------------------------------------------------------------

    \109\ NERC DER Report at 3.
    \110\ Id. at 9.
    \111\ Id. at 35.
---------------------------------------------------------------------------

    51. Similarly, in the WI Base Case IBR Review, NERC and WECC 
observed that IBR-DERs are not widely included in WECC base cases and 
noted that this could pose a ``risk for the creation of a reasonable 
starting case for entities neighboring those with notable [IBR-] DER 
penetrations.'' \112\ NERC and WECC also observed that planners and 
operators do not have enough information about generators (including 
IBR information) to develop a complete and accurate base case.\113\
---------------------------------------------------------------------------

    \112\ WI Base Case IBR Review at 2.
    \113\ Id. at 1-4.
---------------------------------------------------------------------------

b. Operational Studies
    52. Operators must perform various operational studies, including 
operational planning analyses, real-time monitoring, real-time 
assessments and other analyses that include all resources necessary to 
adequately assess the performance of the Bulk-Power System for normal 
and contingency conditions.\114\ The Reliability Standards do not 
require operators to include the performance and behavior of both 
individual and aggregate registered IBRs and unregistered IBRs, as well 
as IBR-DERs in the aggregate (e.g., IBRs tripping or entering momentary 
cessation individually or in the aggregate) in operational studies used 
to identify potential system operating limits and interconnection 
reliability operating limit exceedances and to identify any potential 
reliability risks related to instability, cascading, or uncontrolled 
separation. In addition, models of registered IBRs, unregistered IBRs, 
as well as models of IBR-DERs in the aggregate are generally not 
accurate (as discussed above), which invalidates the operational 
studies, as evidenced by numerous Bulk-Power System IBR disturbance 
events seen since 2016.\115\ For example, in the FERC, NERC, and 
Regional Entity Joint Report on Real-time Assessments, ``[s]everal 
participants expressed concern that Contingencies may now change 
seasonally because of the decline in system inertia due to the growing 
number of Inverter-Based Resources in the generation mix. This placed a 
greater onus on the participant to conduct in-depth and up-to-date 
studies to ensure all stability Contingencies on its system are 
identified.'' \116\
---------------------------------------------------------------------------

    \114\ See Reliability Standard TOP-001-5 (Transmission 
Operations), Requirements R10, R11, R13; Reliability Standard TOP-
002-4 (Operations Planning), Requirements R1, R4; Reliability 
Standard IRO-008-2 (Reliability Coordinator Operational Analyses and 
Real-time Assessments), Requirements R1, R4; Reliability Standard 
IRO-002-7 (Reliability Coordination--Monitoring and Analysis), 
Requirement R5.
    \115\ See Modeling and Studies Report at iv (finding that ``Many 
of the dynamic models that were supplied by [generator owners] as 
part of the NERC Alert process had modeling errors or inaccuracies 
and were unusable to the [transmission planner] and [planning 
coordinator].''); see also NERC DER Report at vi (expressing that 
``Today, the effect of aggregated [IBR-]DER is not fully represented 
in [Bulk-Power System] models and operating tools.'').
    \116\ FERC, NERC, Regional Entities, Joint Report on Real-time 
Assessments, 13-14 (July 2021), https://www.ferc.gov/media/ferc-and-ero-enterprise-joint-report-real-time-assessments.
---------------------------------------------------------------------------

    53. In the Loss of Solar Resources Alert II, NERC recommended that 
reliability coordinators, transmission operators, and balancing 
authorities ``[t]rack, retain, and use the updated IBR dynamic model(s) 
. . . of existing resource performance that are supplied by the 
Generator Owners to perform assessments and system analyses to identify 
any potential reliability risks related to instability, cascading, or 
uncontrolled separation . . . .'' \117\ In addition, the NERC DER 
Report explained that IBR-DERs do not follow a dispatch signal and are 
generally not visible to Bulk-Power System operators.\118\ The NERC DER 
Report recommended that all components of the Bulk-Power System, 
including IBR-DERs, be modeled either directly or in aggregate, with 
sufficient fidelity to enable dynamic and steady-state models to 
provide meaningful and accurate simulations of actual system 
performance.\119\
---------------------------------------------------------------------------

    \117\ Loss of Solar Resources Alert II at 4-5.
    \118\ NERC DER Report at 3; see also IBR Performance Guideline 
at 65.
    \119\ NERC DER Report at iv, 9.
---------------------------------------------------------------------------

4. IBR Performance
    54. Essential reliability services, such as frequency and voltage 
support, serve as the basis for reliably operating the Bulk-Power 
System. Without the availability of essential reliability services, the 
system would experience instability, voltage collapse, or uncontrolled 
separation.\120\ NERC's Essential Reliability Services Concept Paper 
initially identified two essential reliability services building 
blocks--voltage support and frequency support.\121\ Some components of 
these services are provided automatically by synchronous generation due 
to their physical and mechanical properties. By contrast, IBRs must be 
configured and programmed to provide these services, and the 
Reliability Standards do not require registered IBRs to provide such 
services.
---------------------------------------------------------------------------

    \120\ Essential Reliability Services Concept Paper at iii.
    \121\ Id.
---------------------------------------------------------------------------

    55. The Commission previously revised the pro forma Large Generator 
Interconnection Agreement and the pro forma Small Generator 
Interconnection Agreement to require newly interconnecting generating 
facilities to address certain issues related to essential reliability 
services. In Order No. 827, the Commission required all newly 
interconnecting non-synchronous generating facilities to provide 
dynamic reactive power within the range of 0.95 leading to 0.95 lagging 
at the high-side of the generator substation as a condition of 
interconnection unless the transmission provider establishes a 
different power factor range, eliminating an earlier exemption for wind 
generation.\122\ In Order No. 828, the Commission required newly 
interconnecting small generating facilities to have the capability to 
``ride through abnormal frequency and voltage events and not disconnect 
during such events.'' \123\ Finally, in Order No. 842,

[[Page 74554]]

the Commission required newly interconnecting generating facilities 
``to install, maintain, and operate equipment capable of providing 
primary frequency response as a condition of interconnection.'' \124\
---------------------------------------------------------------------------

    \122\ Reactive Power Requirements for Non-Synchronous 
Generation, Order No. 827, 81 FR 40793 (June 23, 2016), 155 FERC ] 
61,277, at PP 1-2 (2016).
    \123\ Requirements for Frequency & Voltage Ride Through 
Capability of Small Generating Facilities, Order No. 828, 81 FR 
50290 (Aug. 1, 2016), 156 FERC ] 61,062, at P 1 (2016). The 
Commission went on to explain that it ``continues to affirm that 
this Final Rule is not intended to interfere with state 
interconnection procedures or agreements in any way. The pro forma 
SGIA applies only to interconnections made subject to a 
jurisdictional open access transmission tariff (OATT) for the 
purposes of jurisdictional wholesale sales.'' Id. P 12.
    \124\ Essential Reliability Servs. & the Evolving Bulk-Power 
Sys.--Primary Frequency Response, Order No. 842, 162 FERC ] 61,128 
at P 1.
---------------------------------------------------------------------------

a. Frequency Ride Through
    56. The Reliability Standards do not account for the difference 
between registered IBRs' and synchronous facilities' responses during 
normal and contingency conditions. IBR technology is different than 
synchronous generation technologies. For instance, IBR ride through 
capability must be configured and programmed for IBRs to be able to 
ride through frequency disturbances. Synchronous resources will 
automatically ride through a disturbance because they are synchronized 
(i.e., connected at identical speeds) to the electric power system and 
physically linked to support the system frequency during frequency 
fluctuations by continuing to produce real and reactive power. The 
frequency of an interconnection depends on the instantaneous balance 
between load and generation resources to which all resources must 
contribute during both normal and contingency conditions. This requires 
generation resources to remain connected to the grid and continue to 
support grid frequency (i.e., ride through) for either loss of 
generation (underfrequency) or loss of load (overfrequency) related 
frequency deviations.
    57. Reliability Standard PRC-024-3 (Frequency and Voltage 
Protection Settings for Generating Resources) does not include 
frequency ride through performance requirements that address the unique 
protection and control functions of IBRs. In particular, the 
Reliability Standard PRC-024-3 requirement for specific relay 
protection frequency settings does not address momentary cessation. As 
a result, registered IBRs are not required to continually produce real 
power and support frequency inside the ``no trip zone'' during a 
frequency excursion.\125\
---------------------------------------------------------------------------

    \125\ Reliability Standard PRC-024-3, Attachment 1, nn.8, 9. 
There is no explicitly stated expected performance requirements for 
IBRs while system operating conditions are within the no-trip zone. 
Therefore, IBRs could continue to act adversely in response to 
normally cleared faults by continuing to exhibit momentary cessation 
and power reduction behaviors.
---------------------------------------------------------------------------

    58. In the Blue Cut Fire Event Report, NERC and WECC found that 
inverters that ``trip instantaneously based on near instantaneous 
frequency measurements are susceptible to erroneous tripping during 
transients generated by faults'' on the Bulk-Power System.\126\ In 
response, NERC and WECC recommended a review of Reliability Standard 
PRC-024-2 to determine whether to modify it for clarity and to ensure a 
more accurate representation of Bulk-Power System frequency 
measurement.\127\ Shortly after the Blue Cut Fire Event Report, NERC 
also issued the Loss of Solar Resources Alert I identifying and 
recommending corrective action to prevent similar IBR responses in the 
future.\128\
---------------------------------------------------------------------------

    \126\ Blue Cut Fire Event Report at v, 15.
    \127\ Id.
    \128\ Loss of Solar Resources Alert I at 1-2.
---------------------------------------------------------------------------

    59. On July 9, 2020, the Commission approved Reliability Standard 
PRC-024-3, which addressed some of the reliability gaps in Reliability 
Standard PRC-024-2 that NERC found contributed to the outages during 
the August 2016 Blue Cut Fire event system disturbance.\129\ For 
example, Reliability Standard PRC-024-3 clarifies that the ``applicable 
protection does not cause the generating resource to trip or cease 
injecting current within the `no trip zone' during a frequency 
excursion. . . .'' \130\ In addition, Reliability Standard PRC-024-3 
requires that frequency be calculated over a window of time and 
clarifies that instantaneous trip settings based on instantaneously-
calculated frequency measurement are not permissible.\131\ However, 
Reliability Standard PRC-024-3 does not require registered IBRs (or any 
generator) to remain connected to the Bulk-Power System and to continue 
to produce real power and support frequency inside the ``no trip 
zone.'' This reliability gap led to NERC and Texas RE recommending in 
the 2021 Odessa Disturbance Report the development of a new ride 
through standard to replace Reliability Standard PRC-024-3 focusing 
specifically on generator-ride through performance.\132\
---------------------------------------------------------------------------

    \129\ N. Am. Elec. Reliability Corp., Docket No. RD20-7-000 
(July 9, 2020) (delegated letter order).
    \130\ Cessation of current injection was not included in 
Reliability Standard PRC-024-2. See also Reliability Standard PRC-
024-3, Requirement R1 & Attachment 1, n.9.
    \131\ Reliability Standard PRC-024-3, Attachment 1, n.9.
    \132\ Odessa Disturbance Report at 30.
---------------------------------------------------------------------------

b. Voltage Ride Through
    60. The Reliability Standards do not require registered IBRs to 
continually produce real power and support voltage inside the ``no trip 
zone'' during a voltage excursion. The Reliability Standards also do 
not have voltage ride through performance requirements that address the 
unique protection and control functions of registered IBRs that can 
cause tripping and momentary cessation, even when the IBR voltage 
protection settings are compliant with Reliability Standard PRC-024-3. 
Keeping generation resources connected to the grid during and after a 
Bulk-Power System disturbance is critical to maintaining reliability. 
During both Bulk-Power System fault and post-fault periods, the 
transmission system experiences voltage depressions. Additionally, the 
transmission system may experience high voltages during post-fault 
recovery periods. Voltage fluctuations during system disturbances may 
lead to IBRs tripping and momentary cessation, which can exacerbate 
Bulk-Power System recovery.
    61. Since first identifying that IBRs momentarily cease current 
injection or trip in response to voltage fluctuations during system 
disturbances, NERC has continued to find that the majority of installed 
inverters fail to continuously inject active or reactive current during 
abnormal voltages (i.e., ride through).\133\ Through event reports, 
NERC and WECC have recommended that momentary cessation should not be 
used for new IBRs and ``should be eliminated or mitigated to the 
greatest extent possible for existing [IBRs] connected to the [Bulk-
Power System].'' and WECC also noted that for existing IBRs with an 
equipment limitation that requires momentary cessation, ``active 
current injection following voltage recovery should be restored very 
quickly (within 0.5 seconds).'' \134\
---------------------------------------------------------------------------

    \133\ Blue Cut Fire Event Report at 9; Canyon 2 Fire Event 
Report at 14, 16-17, 20; Angeles Forest and Palmdale Roost Events 
Report at 13, 15, 19; San Fernando Disturbance Report at iv, 2-9.
    \134\ Canyon 2 Fire Event Report at 19.
---------------------------------------------------------------------------

    62. In addition to event reports, NERC has also recommended in the 
Loss of Solar Resources Alert II that registered IBR owners and 
operators as well as unregistered IBR owners and operators take action 
to address voltage ride through and ensure the timely restoration of 
current injection following momentary cessation by all inverter-based 
resources connected to the Bulk-Power System.\135\ NERC also 
recommended that solar PV IBR owners should ``[w]ork with their 
inverter manufacturer(s) to identify the changes that can be made to 
eliminate momentary cessation of current injection to the greatest 
extent possible, consistent with equipment capability.'' \136\
---------------------------------------------------------------------------

    \135\ Loss of Solar Resources Alert II at 1.
    \136\ Id. at 2-3.

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[[Page 74555]]

    63. For IBRs for which momentary cessation cannot be eliminated 
entirely, NERC recommended that generator owners should identify the 
changes that can be made to inverter settings to minimize the impact of 
momentary cessation on the Bulk-Power System.\137\ NERC also 
recommended that solar PV IBR owners should ``consult with their 
inverter manufacturer(s) and their PV panel manufacturer(s) to 
implement inverter DC reverse current protection settings based on 
equipment limitations, such that the resource will not trip 
unnecessarily during high voltage transients on the [Bulk-Power 
System.]'' \138\ Also in the IBR Performance Guideline, NERC recommends 
reducing the recovery delay on the order of one to three electrical 
cycles and return to full active power within one second. The only 
exception to the return to service recommendation is when the 
transmission planner or generation interconnection studies specify a 
longer period to return to normal operations. Longer restoration 
periods would require other essential reliability services from other 
generators to be deployed to arrest frequency decline and provide 
voltage support when IBRs trip or do not return to service in a timely 
manner.\139\
---------------------------------------------------------------------------

    \137\ Id. at 3.
    \138\ Id. at 4.
    \139\ NERC IBR Performance Guideline at 13, 68.
---------------------------------------------------------------------------

c. Post-Disturbance IBR Ramp Rate Interactions
    64. The Reliability Standards do not ensure that all generation 
resources that momentarily cease operation following a system 
disturbance return to pre-disturbance output levels without impeded 
ramp rates. In the Canyon 2 Fire Event Report, NERC and WECC explained 
that impeded ramp rates need to be ``remediated to ensure [Bulk-Power 
System] transient and frequency stability.'' \140\ Further, NERC and 
WECC found that IBR ramp rates are artificially bounded, resulting in 
IBRs returning to pre-disturbance outputs slower than desired--ranging 
from seconds to several minutes--because plant-level controller ramp 
rate limits used for balancing generation and load are being applied to 
IBRs following momentary cessation.\141\ For IBRs that cannot eliminate 
momentary cessation, NERC and WECC recommended that active current 
injection should not be restricted by a plant-level controller or other 
limits on ramp rates.\142\ NERC and WECC also recommended that IBR 
owners should remediate post-disturbance ramp rate limitations in close 
coordination with their balancing authority and inverter manufacturers 
while ensuring that ramp rates are enabled appropriately to control 
generation-load balance.\143\
---------------------------------------------------------------------------

    \140\ Canyon 2 Fire Event Report at 9.
    \141\ Id. at 9-11, 19; see also Blue Cut Fire Event Report at 15 
(observing that during the Blue Cut Fire Event, some inverters that 
went into momentary cessation mode returned to pre-disturbance 
levels at a slow ramp rate).
    \142\ Canyon 2 Fire Event Report at v.
    \143\ Id. See also Loss of Solar Resources Alert II at 3 
(recommending that IBR solar PV generators owners ensure that 
inverter restoration from momentary cessation should not be impeded 
by plant-level control ramp rates); see also Angeles Forest and 
Palmdale Roost Events Report at 14-15 (reiterating the findings and 
recommendations from the Loss of Solar Resources Alert II); see also 
San Fernando Disturbance Report at iv (explaining that some IBRs 
returned to pre-disturbance power output levels quickly (i.e., 
around one second) while the majority of IBRs had longer ramp rates 
and required substantially more time to return to pre-disturbance 
power output levels).
---------------------------------------------------------------------------

d. Phase Lock Loop Synchronization
    65. The Reliability Standards do not require that all generation 
resources maintain voltage phase angle synchronization with the Bulk-
Power System grid voltage during a system disturbance. IBRs will 
momentarily cease current injection into the grid due to protection and 
control settings during Bulk-Power System disturbance events if IBRs 
lose synchronization with grid voltage (i.e., phase lock loop loss of 
synchronism). The Odessa Report explained that phase lock loop loss of 
synchronism was the largest contributor to the reduction of solar PV 
output during the reported Bulk-Power System disturbance event.\144\
---------------------------------------------------------------------------

    \144\ Odessa Report at 8.
---------------------------------------------------------------------------

    66. For IBRs, an inverter phase lock loop ``continually monitors 
the phase angle difference between the inverter [AC] voltage command 
and the grid-side [AC] voltage.'' \145\ The phase lock loop also 
``adjusts the internal phase angle of current injection to remain 
synchronized with the [AC] grid.'' \146\ Synchronous generation 
resources do this automatically through electromagnetic coupling 
whereby mechanical energy from the turbine is converted to electrical 
energy in the magnetic field of the generator, which is synchronized 
with the system.\147\ For certain disturbances, a ``rapid change in 
inverter terminal phase angle can pose challenges for the [phase lock 
loop] to track the terminal voltage angle.'' \148\ In some instances, a 
phase lock loop ``loss of synchronism'' may occur.\149\ Proper tracking 
of voltage phase angle is required for a successful and effective 
synchronization of the inverter with the grid.
---------------------------------------------------------------------------

    \145\ IBR Interconnection Requirements Guideline at 9 (footnotes 
omitted).
    \146\ Id.
    \147\ Edvard, Mysterious Synchronous Operation of Generator 
Solved, Electrical-Engineering-Portal.com, (Jun. 2013), https://electrical-engineering-portal.com/mysterious-synchronous-operation-of-generator.
    \148\ IBR Interconnection Requirements Guideline at 9.
    \149\ Id. at 10 (this is a protective function that operates 
when the angle difference between the phase generated by the phase 
lock loop and the grid phase exceeds a threshold for a predetermined 
period, typically on the order of a couple of milliseconds).
---------------------------------------------------------------------------

    67. The Canyon 2 Fire Event Report found that some IBRs experienced 
a momentary loss of synchronism with the AC grid waveform during the 
disturbance, which resulted in protective action opening the primary 
circuit breaker followed by a five-minute restart action.\150\ NERC and 
WECC recommended that IBRs should ``ride through momentary loss of 
synchronism'' during Bulk-Power System disturbances and that they 
should continue to inject current into the Bulk-Power System during the 
disturbance.\151\
---------------------------------------------------------------------------

    \150\ Canyon 2 Fire Event Report at 15-16, 20.
    \151\ Id.
---------------------------------------------------------------------------

IV. Proposed Directives

    68. We preliminarily find that the Reliability Standards do not 
adequately address the impacts of IBRs on the reliable operation of the 
Bulk-Power System. Informed by the IBR events, reports, alerts, and 
guidelines discussed above, we preliminarily find that changes to the 
Reliability Standards are necessary to appropriately address IBRs and 
their impacts on Bulk-Power System operations.
    69. Pursuant to section 215(d)(5) of the FPA and Sec.  39.5(f) of 
the Commission's regulations, we therefore propose to direct NERC to 
develop and submit new or modified Reliability Standards that address 
the impacts of IBRs on the reliable operation of the Bulk-Power System 
as described in more detail below. Given the current and projected 
increased proportion of IBRs within the Bulk-Power System generation 
fleet,\152\ we propose to direct NERC to develop new or modified 
Reliability Standards that address: (1) IBR data sharing; (2) IBR model 
validation; (3) IBR planning and operational studies; and (4) 
registered IBR performance requirements.
---------------------------------------------------------------------------

    \152\ See, e.g., 2020 LTRA Report at 9.
---------------------------------------------------------------------------

    70. We appreciate that NERC has initiated several standard drafting 
projects relating to IBRs,\153\ but we

[[Page 74556]]

believe that a comprehensive review and development of new or modified 
Reliability Standards to address IBRs is necessary to assure that IBRs 
are properly considered in Bulk-Power System planning and that their 
operational characteristics--such as momentary cessation--are 
addressed.\154\ Developing new or modified Reliability Standards to 
comprehensively address the reliability impacts of IBRs will help 
ensure the reliable operation of the Bulk-Power System as the 
transition to a future resource mix that includes a high level of IBR 
penetration continues.
---------------------------------------------------------------------------

    \153\ NERC 2022-2024 Reliability Standards Development Plan.
    \154\ See 2021 Solar PV Disturbances Report, vi, 30 (stating 
that the report ``strongly reiterates the recommendations in the 
Odessa Disturbance Report regarding the need to modernize and update 
the . . . Reliability Standards.'').
---------------------------------------------------------------------------

    71. Given the variety of concerns related to IBRs, there may be 
efficiencies in developing a new IBR-specific Reliability Standard or 
Standards that address IBR issues in a comprehensive manner. Further, 
considering the directives in the related IBR registration order issued 
concurrently with this NOPR,\155\ a new Reliability Standard or 
Standards may also be more easily developed for the newly registered 
IBR-only generator owners and operators of currently unregistered IBRs 
that fall outside the current bulk electric system definition but that, 
in the aggregate, materially impact the reliable operation of the Bulk-
Power System.\156\ We do not propose to direct any specific method for 
addressing the reliability concerns discussed herein; rather, NERC has 
the discretion, subject to Commission review and approval, to address 
the reliability concerns by developing one or more new Reliability 
Standards or modifying currently effective Reliability Standards.
---------------------------------------------------------------------------

    \155\ See Registration of Inverter-based Resources, 181 FERC ] 
61,124 at P 32 (directing that NERC identify and register 
unregistered IBRs that, in the aggregate, have a material impact on 
the reliable operation of the Bulk-Power System, but that are not 
currently required to be registered with NERC under the [bulk 
electric system] definition.'').
    \156\ Id. P 33 (``NERC may determine that the full set of 
Reliability Standard Requirements otherwise applicable to generator 
owners and operators need not apply to currently unregistered IBR 
generator owners and operators when they are registered.'' (citation 
omitted)).
---------------------------------------------------------------------------

    72. We propose to direct NERC to submit a compliance filing within 
90 days of the effective date of the final rule in this proceeding. 
That compliance filing shall include a detailed, comprehensive 
standards development and implementation plan explaining how NERC will 
prioritize the development and implementation of new or modified 
Reliability Standards. In its compliance filing, NERC should explain 
how it is prioritizing its IBR Reliability Standard projects to meet 
the directives in the final rule, taking into account the risk posed to 
the reliability of the Bulk-Power System, standard development projects 
already underway, resource constraints, and other factors as necessary.
    73. We propose to direct NERC to use a staggered approach that 
would result in NERC submitting new or modified Reliability Standards 
in three stages: (1) new or modified Reliability Standards including 
directives related to registered IBR failures to ride through frequency 
and voltage variations during normally cleared Bulk-Power System faults 
shall be filed with the Commission within 12 months of Commission 
approval of the plan; (2) new or modified Reliability Standards 
addressing the interconnected directives related to registered IBR, 
unregistered IBR, and IBR-DER data sharing, registered IBR disturbance 
monitoring data sharing, registered IBR, unregistered IBR, and IBR-DER 
data and model validation, and registered IBR, unregistered IBR, and 
IBR-DER planning and operational studies shall be filed with the 
Commission within 24 months of Commission approval of the plan; and (3) 
new or modified Reliability Standards including the remaining 
directives for post-disturbance ramp rates and phase-locked loop 
synchronization shall be filed with the Commission within 36 months of 
Commission approval of the plan. We believe this staggered approach to 
standard development may be necessary based on the scope of work 
anticipated and that specific target dates will provide a valuable tool 
and incentive to NERC to timely address the directives in the final 
rule.
    74. NERC should also reflect in its compliance filing that the 
proposed directives for individual and aggregate registered IBRs and 
unregistered IBRs, as well as IBR-DERs in the aggregate, related to 
data sharing, validation, and use in studies are interdependent. For 
example, data models and validation build and rely upon the data 
sharing directives. Similarly, the planning and operational study 
directives require the use of validated models and data sharing. We 
believe that this proposal strikes a reasonable balance between the 
need to timely implement identified improvements to the Reliability 
Standards that will further Bulk-Power System reliability and the need 
for NERC to develop modifications with industry input using its open, 
stakeholder process.
    75. We seek comments from NERC and other interested entities on 
this staggered approach, including the 90-day timeframe to submit a 
compliance filing with a development and implementation plan, and on 
all other proposals in this NOPR.

A. IBR and IBR-DER Data Sharing

    76. We preliminarily find that the current Reliability Standards 
are inadequate to ensure that sufficient data of registered IBRs and 
unregistered IBRs, and IBR-DER data in the aggregate is provided to the 
registered entities responsible for planning, operating, and analyzing 
disturbances on the Bulk-Power System. The currently effective 
Reliability Standards, such as TOP-003-4 (Operational Reliability Data) 
and IRO-010-3 (Reliability Coordinator Data Specification and 
Collection), require the data recipient (e.g., transmission operator, 
reliability coordinator) to specify a list of data to be provided, and 
obligates other identified registered entities (e.g., generator owner, 
generator operator, transmission owner, distribution provider) to 
provide the specified data. Although Reliability Standards TOP-003-4 
and IRO-010-3, along with other data-related Reliability Standards 
(including MOD-032-1 and PRC-002-2) are effective and enforceable, we 
preliminarily find that these Reliability Standards do not require 
generator owners, generators operators, transmission owners, and 
distribution providers to provide data that represents the behavior of 
both individual and aggregate registered IBRs and unregistered IBRs, as 
well as IBR-DERs in the aggregate, at a sufficient level of fidelity 
for planners and operators to accurately plan, operate, and analyze 
disturbances on the Bulk-Power System.
    77. To address this gap in the Reliability Standards, we propose to 
direct NERC to develop new or modified Reliability Standards that 
identify: (1) the registered entities that must provide certain data of 
registered IBRs and unregistered IBRs, as well as IBR-DER data in the 
aggregate; (2) the recipients of that registered IBR, unregistered IBR, 
and IBR-DER data; (3) the minimum categories or types of registered 
IBR, unregistered IBR, and IBR-DER related data that must be provided; 
and (4) the timing and periodicity for the provision of registered IBR, 
unregistered IBR, and IBR-DER data needed for modeling, operations, and 
disturbance analysis to the appropriate registered entities and the 
review of that data by those entities.
    78. Further, we propose to direct NERC to ensure that the new or 
modified Reliability Standards require registered generator owners and 
generator operators of registered IBRs to provide registered IBR-
specific

[[Page 74557]]

modeling data and parameters (e.g., steady-state, dynamic and short 
circuit modeling information, and control settings for momentary 
cessation and ramp rates) that are complete and accurate to their 
planning coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities that are responsible 
for planning and operating the Bulk-Power System. This approach would 
provide the registered entities responsible for planning and operating 
the Bulk-Power System with accurate data on registered IBRs. We propose 
to direct NERC to include technical criteria for having disturbance 
monitoring equipment at buses and elements of registered IBRs to ensure 
disturbance monitoring data is available to the planners and operators 
for analyzing disturbances on the Bulk-Power System and to validate 
registered IBR models.
    79. We also preliminarily find that planning coordinators and other 
entities also need modeling data and parameters from both unregistered 
IBRs as well as IBR-DERs in the aggregate to assure greater accuracy in 
modeling. We propose to direct that the new or modified Reliability 
Standards addressing IBR data sharing require transmission owners to 
provide modeling data and parameters (e.g., steady-state, dynamic and 
short circuit modeling information, and control settings for momentary 
cessation and ramp rates) for unregistered IBRs in their transmission 
owner areas where the unregistered IBRs that individually or in the 
aggregate materially affect the reliable operation of the Bulk-Power 
System. Similarly, where entities that own or operate IBR-DERs that, in 
the aggregate, materially affect the reliability of the Bulk-Power 
System and are not subject to compliance with Reliability Standards, we 
propose to direct that the new or modified Reliability Standards 
addressing IBR data sharing require that the distribution provider 
provide modeling data and parameters for IBR-DERs in the aggregate 
connected in its distribution provider area.\157\
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    \157\ NERC, Reliability Guideline: Parameterization of the DER A 
Model, 8-16 (Sept. 2019), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf.
---------------------------------------------------------------------------

    80. This approach would be similar to other Reliability Standards 
that require transmission owners and distribution providers to provide 
certain planning and operational data received from unregistered 
entities.\158\ Moreover, given the small size and location of many of 
the IBR-DERs on the distribution system, we recognize that it may not 
be practical for distribution providers to provide modeling data and 
parameters to model individual IBR-DERs directly. Instead, the new or 
modified Reliability Standards should permit distribution providers to 
provide IBR-DER modeling data and parameters in the aggregate or 
equivalent for IBR-DERs interconnected to their distribution systems 
(e.g., IBR-DERs in the aggregate and modeled by resource type such as 
wind or solar PV, or IBR-DERs in the aggregate and modeled by 
interconnection requirements performance to represent different steady-
state and dynamic behavior).\159\
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    \158\ This approach is consistent with certain currently 
effective Reliability Standards. See, e.g., Reliability Standard 
IRO-010-2 (Reliability Coordinator Data Specification and 
Collection) Requirement R1 (providing that ``[t]he Reliability 
Coordinator shall maintain a documented specification for the data . 
. . including non-[bulk electric system] data''(emphasis added)), 
Requirement R2 (providing that ``[t]he Reliability Coordinator shall 
distribute its data specification to entities''), Requirement R3 
(providing that ``[e]ach . . . Transmission Owner, and Distribution 
Provider receiving a data specification in Requirement R2 shall 
satisfy the obligations of the documented specifications''); 
Reliability Standard PRC-006-3 (Automatic Underfrequency Load 
Shedding) Requirement R8 (requiring that a UFLS entity, i.e., 
relevant transmission owner and distribution provider, ``provide 
data to its Planning Coordinator(s)'').
    \159\ NERC DER Report at 7 (explaining ``a certain degree of 
simplification may be needed either by model aggregation (i.e., 
clustering of models with similar performance), by derivation of 
equivalent models (i.e., reduced-order representation), or by a 
combination of the two.''). See also NERC, Reliability Guideline: 
Parameterization of the DER A Model, (Sept. 2019), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf.
---------------------------------------------------------------------------

    81. We believe that these proposed directives will ensure that 
entities such as planning coordinators and reliability coordinators 
receive accurate and complete data about IBRs, both registered IBRs and 
unregistered IBRs, as well as IBR-DERs in the aggregate to properly 
plan, operate, and analyze performance on the Bulk-Power System to 
ensure reliable operations.

B. IBR and IBR-DER Data and Model Validation

    82. We preliminarily find that the existing Reliability Standards 
are inadequate to ensure that planners and operators: (1) have the 
steady state, dynamic, and short circuit models of the elements that 
make up generation, transmission, and distribution facilities that 
accurately reflect the generator behavior in steady state and dynamic 
conditions; (2) have dynamic models (i.e., models of equipment that 
reflect the equipment's behavior during various grid conditions and 
disturbances) that accurately represent the dynamic performance of all 
generation resources, including momentary cessation when applicable; 
(3) validate and update resource models by comparing the provided data 
and resulting models against actual operational behavior to achieve and 
maintain necessary accuracy of their resource models; and (4) have 
interconnection-wide planning and operational models that represent all 
generation resources, including: registered IBRs, unregistered IBRs, 
and IBR-DERs; synchronous generation; and load resource models. System 
planners and operators need accurate planning, operational, and 
interconnection-wide models to ensure reliable operation of the system.
    83. We therefore propose to direct NERC to submit to the Commission 
for approval one or more new or modified Reliability Standards that 
would ensure that all necessary models are validated. Specifically, 
NERC should ensure that the Reliability Standards require: (1) 
generator owners to provide validated registered IBR models to the 
planning coordinators for interconnection-wide planning and operational 
models; (2) require transmission owners to provide validated 
unregistered IBR models to the planning coordinators for 
interconnection-wide planning and operational models; and (3) require 
distribution providers to provide validated models of IBR-DERs in the 
aggregate (e.g., IBR-DERs in the aggregate and modeled by resource type 
such as wind or solar PV, or IBR-DERs in the aggregate and modeled by 
interconnection requirements performance to represent different steady-
state and dynamic behavior) to the planning coordinators for 
interconnection-wide planning and operational models. Further, NERC 
should ensure that the new or modified Reliability Standards require 
models of individual registered IBRs and unregistered IBRs, as well as 
IBR-DERs in the aggregate to represent the dynamic behavior of these 
IBRs at a sufficient level of fidelity for planners and operators to 
perform valid facility interconnection, planning, and operational 
studies on a basis comparable to synchronous generation resources.
    84. The Reliability Standards do not require a generator owner to 
provide verified models and data for IBR-specific controls (e.g., power 
plant central controller functions and protection system settings) and 
do not require verified dynamic models from the transmission owner for 
unregistered IBRs or require verified IBR-DERs dynamic models in the 
aggregate from distribution providers. We therefore

[[Page 74558]]

propose to direct that the proposed new or modified Reliability 
Standards account for the technological differences between Bulk-Power 
System IBRs and synchronous generation resources. We also propose to 
direct NERC to require generator owners of registered IBRs and 
transmission owners that have unregistered IBRs on their system to 
ensure that the dynamic models provided to the planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities accurately represent the dynamic 
performance of registered IBR and unregistered IBR facilities, 
including momentary cessation and/or tripping, including all ride 
through behavior. Further, we propose to direct NERC to require 
distribution providers that have IBR-DERs on their system to ensure 
that the aggregated dynamic models provided to the planning 
coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities accurately represent 
the dynamic performance of IBR-DER facilities in the aggregate, 
including momentary cessation and/or tripping, including all ride -
through behavior (e.g., IBR-DERs in aggregate modeled by 
interconnection requirements performance to represent different steady-
state and dynamic behavior).
    85. We also preliminarily find that there is a coordination gap 
among registered entities that build and verify interconnection-wide 
cases. Reliability Standards MOD-032-1 and MOD-033-2 functional 
entities and designees are not required to work collaboratively to 
create interconnection-wide cases that accurately reflect real-world 
interconnection-wide IBR performance and behavior. Therefore, we 
propose to direct NERC to ensure that the new or modified Reliability 
Standards require planning coordinators, transmission planners, 
reliability coordinators, transmission operators, and balancing 
authorities to validate, coordinate, and keep up-to-date in a timely 
manner \160\ the verified data and models of registered IBRs, 
unregistered IBRs, and IBR-DERs in the aggregate by comparing their 
data and resulting models against actual operational behavior to 
achieve and maintain necessary modeling accuracy of individual and 
aggregate registered IBR and unregistered IBR performance and 
behaviors, as well as performance and behaviors of IBR-DERs in the 
aggregate.
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    \160\ Panhandle Report at 19 (recommending that the performance 
validation feedback loop is addressed in a timely manner).
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    86. Finally, without approved generator models that accurately 
reflect the generator behavior in steady state and dynamic conditions, 
we preliminarily find that planners and operators are unable to 
adequately predict IBR behavior and their subsequent impact on the 
Bulk-Power System.\161\ The Reliability Standards do not require the 
use of NERC's approved component models, instead models are referred to 
generally in Reliability Standard MOD-032-1, Attachment 1.\162\ We 
therefore propose to require that the new or modified Reliability 
Standards require the use of approved industry IBR models that 
accurately reflect the behavior of IBRs during both steady state and 
dynamic conditions. One way to do this would be to reference NERC's 
approved model list in the Reliability Standards and require that only 
those models be used when developing planning, operational, and 
interconnection-wide models. The proposed directives are consistent 
with the recommendations in NERC reports.\163\
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    \161\ NERC Standardized Powerflow Parameters and Dynamics Models 
(explaining that there is a growing need for accurate 
interconnection[hyphen]wide powerflow and dynamics simulations that 
analyze phenomena such as: frequency response, inter-area 
oscillations, and interactions between the growing numbers of wide-
area control and protections systems).
    \162\ Reliability Standard MOD-032-1, Attachment 1 (explaining 
that if a user-written model(s) is submitted in place of a generic 
or library model, it must include the characteristics of the model, 
including block diagrams, values and names for all model parameters, 
and a list of all state variables).
    \163\ See, e.g., Modeling and Studies Report at 37 (recommending 
revising Reliability Standards to ensure that large disturbance 
behavior of IBRs is verified); WI Base Case IBR Review at v 
(recommending that IBR owners ensure that all data fields are 
reported correctly and that transmission planners and planning 
coordinators ``should verify that the data fields are submitted 
correctly'').
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C. IBR and IBR-DER Planning and Operational Studies

    87. We preliminarily find that the existing Reliability Standards 
are inadequate to ensure planning and operational studies: (1) assess 
performance and behavior of both individual and aggregate registered 
IBRs and unregistered IBRs as well as IBR-DERs in the aggregate; (2) 
have and use validated modeling and operational data for individual 
registered IBRs and unregistered IBRs, as well as IBR-DERs in the 
aggregate; and (3) account for the impacts of both individual and 
aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in 
the aggregate, within and across planning and operational boundaries 
for normal operations and contingency event conditions. Planning and 
operational studies must use validated IBR modeling and operational 
data to ensure studies account for the actual behavior of both 
individual and aggregate registered IBRs and unregistered IBRs, as well 
as IBR-DERs in the aggregate.
1. Planning Studies
    88. We preliminarily find that the Reliability Standards do not 
ensure accurate planning studies of Bulk-Power System performance over 
a broad spectrum of system conditions and following a wide range of 
probable contingencies that includes all resources. Inaccurate planning 
assessments may lead to false expectations that system performance 
requirements are met and may inadvertently mask potential reliability 
risks in planning and operations. We therefore propose to direct NERC 
to submit to the Commission for approval one or more new or modified 
Reliability Standards that would require planning coordinators and 
transmission planners to include in their planning assessments the 
study and evaluation of performance and behavior of individual and 
aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in 
the aggregate, under normal and contingency system conditions in their 
planning area. We further propose that the planning assessments include 
the study and evaluation of the ride through performance (e.g., 
tripping and momentary cessation conditions) of such IBRs in their 
planning area for stability studies on a comparable basis to 
synchronous generation resources. The proposed Reliability Standard(s) 
would also require planning coordinators and transmission planners to 
consider the individual and aggregate behavior of registered IBRs and 
unregistered IBRs, as well as IBR-DERs in the aggregate, using planning 
models of their area, and, using interconnection-wide area planning 
models, IBR behavior in adjacent and other planning areas that 
adversely impacts a planning coordinator's or transmission planner's 
area during a disturbance event. We believe that this is needed because 
registered IBRs, unregistered IBRs, and IBR-DERs tend to act in the 
aggregate over a wide area during such an event.\164\
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    \164\ 2021 Solar PV Disturbances Report at v (stating that ``The 
ongoing widespread reduction of solar PV resources continues to be a 
notable reliability risk to the [Bulk-Power System], particularly 
when combined with the additional loss of other generating resources 
on the [Bulk-Power System] and in aggregate on the distribution 
system.''); see also Odessa Disturbance Report at v (stating that 
``[w]hile the ERO has analyzed multiple similar events in 
California, this is the first disturbance involving a widespread 
reduction of solar photovoltaic (PV) resource power output observed 
in the Texas Interconnection.''); Blue Cut Fire Event Report at 2 
(explaining that the system disturbance event was ``impactful 
because of the widespread loss . . . of PV generation.'').

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[[Page 74559]]

2. Operational Studies
    89. We preliminarily find that the Reliability Standards do not 
require that the various operational studies (including operational 
planning analyses, real-time monitoring, real-time assessments and 
other analysis functions) include all resources to adequately assess 
the performance of the Bulk-Power System for normal and contingency 
conditions. We therefore propose to direct NERC to submit to the 
Commission for approval one or more new or modified Reliability 
Standards that would require reliability coordinators and transmission 
operators to include the performance and behavior of both individual 
and aggregate registered IBRs and unregistered IBRs, as well as IBR-
DERs in the aggregate (e.g., IBRs tripping or entering momentary 
cessation individually or in the aggregate) in their operational 
planning analysis,\165\ real-time monitoring, and real-time assessments 
\166\ including non-bulk electric system data and external power system 
network data identified in their data specifications.\167\ We further 
propose to direct NERC to submit to the Commission for approval one or 
more new or modified Reliability Standards that would require balancing 
authorities to include the performance and behavior of both individual 
and aggregate registered IBRs and unregistered IBRs, as well as IBR-
DERs in the aggregate (e.g., resources tripping or entering momentary 
cessation individually or in the aggregate) in their operational 
analysis functions and real-time monitoring.\168\ This proposal is 
consistent with the recommendations in the NERC DER Report, IBR 
Performance Guideline, IBR-DER Data Collection Guideline, and Loss of 
Solar Resources Alert II. These reports indicate that a significant 
amount of IBRs that have been involved in system disturbances were not 
adequately modeled in interconnection-wide cases and tools used to 
study the performance and behavior of both individual and aggregate 
registered IBRs and unregistered IBRs, as well as IBR-DERs in the 
aggregate.\169\ Thus, neighboring operators may be unaware that faults 
in one operator's area can trigger controls actions and trip IBRs in 
another operator's area.
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    \165\ NERC defines operational planning analysis as ``An 
evaluation of projected system conditions to assess anticipated 
(pre-Contingency) and potential (post-Contingency) conditions for 
next-day operations. The evaluation shall reflect applicable inputs 
including, but not limited to, load forecasts; generation output 
levels; Interchange; known Protection System and Special Protection 
System status or degradation; Transmission outages; generator 
outages; Facility Ratings; and identified phase angle and equipment 
limitations. (Operational Planning Analysis may be provided through 
internal systems or through third-party services).'' NERC Glossary.
    \166\ NERC defines real-time assessment as an ``evaluation of 
system conditions using Real-time data to assess existing (pre-
Contingency) and potential (post-Contingency) operating conditions. 
The assessment shall reflect applicable inputs including, but not 
limited to: load, generation output levels, known Protection System 
and Special Protection System status or degradation, Transmission 
outages, generator outages, Interchange, Facility Ratings, and 
identified phase angle and equipment limitations. (Real-time 
Assessment may be provided through internal systems or through 
third-party services).'' Id.
    \167\ See, e.g., Reliability Standard IRO-010-2, Requirement R1, 
part 1.1 and Reliability Standard TOP-003-3 (Operational Reliability 
Data), Requirement R1, part 1.1.
    \168\ See, e.g., Reliability Standard TOP-003-3, Requirement R2, 
part 2.1.
    \169\ Modeling and Studies Report iv-v.
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D. IBR Performance Requirements

    90. We preliminarily find that the Reliability Standards should 
require registered IBRs to ride through system disturbances to support 
essential reliability services. Without the availability of essential 
reliability services, the system would experience instability, voltage 
collapse, or uncontrolled separation.\170\ Therefore, we propose to 
direct NERC to develop new or modified Reliability Standards that would 
require generator owners and generator operators to ensure that their 
registered IBR facilities ride through system frequency and voltage 
disturbances where technologically feasible. Ride through performance 
during system disturbances is necessary for registered IBRs to support 
essential reliability services.\171\ We propose to direct NERC to 
ensure that the proposed new or modified Reliability Standards clearly 
address and document the technical differences and technical 
capabilities between registered IBRs and synchronous generation 
resources in order for registered IBRs to provide support for these 
essential reliability services.\172\
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    \170\ Essential Reliability Services Concept Paper at iii.
    \171\ NERC defines essential reliability services to include 
``necessary operating characteristics'' provided by ``[c]onventional 
generation with large rotating mass,'' which are ``needed to 
reliably operate the North American electric grid.'' NERC explains 
that essential reliability services ``are an integral part of 
reliable operations to assure the protection of equipment, and are 
the elemental `reliability building blocks' provided by 
generation.'' Id.
    \172\ There are similar reliability impacts posed by tripping or 
momentary cessation of unregistered IBRs and IBR-DERs during Bulk-
Power System disturbances; however, we are not proposing to direct 
NERC to develop new or modified Reliability Standards that would 
address unregistered IBR or IBR-DER performance requirements. We 
expect that any currently unregistered IBRs that become registered 
IBRs in the future following an approved NERC workplan in Docket No. 
RD22-4-000 would be required to comply with any applicable new or 
modified IBR performance Reliability Standards proposed in this NOPR 
once those Reliability Standards become enforceable.
---------------------------------------------------------------------------

    91. We also propose to direct NERC to develop new or modified 
Reliability Standards to address other registered IBR performance and 
operational characteristics that can affect the reliable operation of 
the Bulk-Power System, namely, ramp rate interactions and phase-locked 
loop synchronization.
    92. We believe the proposed directives would improve the reliable 
operation of the Bulk-Power System by helping to avoid instability, 
voltage collapse, uncontrolled separation, or islanding.
1. Frequency Ride Through
    93. We preliminarily find that the currently effective Reliability 
Standards do not require registered IBR reliable frequency ride through 
performance during system disturbances. The frequency of an 
interconnection depends on the instantaneous balance between load and 
generation resources to which all resources must contribute during both 
normal and contingency conditions. However, the Reliability Standard 
PRC-024-3 requirement for specific relay protection frequency settings 
does not ensure adequate registered IBR performance because IBRs could 
have protection and control functions that can cause the resource to 
trip or momentarily cease operation even when the IBR frequency 
protection settings are compliant with the standard. We therefore 
propose to direct NERC to submit to the Commission for approval one or 
more new or modified Reliability Standards that would require 
registered IBR generator owners and registered IBR generator operators 
to use appropriate settings (i.e., inverter, plant controller, and 
protection) that will assure frequency ride through during system 
disturbances and that would permit registered IBR tripping only to 
protect the registered IBR equipment. Under this proposal, any new or 
modified Reliability Standards should require registered IBRs to 
continue to produce power and perform frequency support during system 
disturbances. We believe this proposal is consistent with

[[Page 74560]]

recommendations from multiple event reports, including the Blue Cut 
Fire Event Report,\173\ the Odessa Disturbance Report,\174\ and most 
recently the 2021 Solar PV Disturbances Report.\175\
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    \173\ Blue Cut Fire Report at 11-13.
    \174\ Odessa Disturbance Report at vii, 12-13.
    \175\ 2021 Solar PV Disturbances Report at vii, 15, 31.
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2. Voltage Ride Through
    94. We preliminarily find that the currently effective Reliability 
Standards do not adequately address registered IBR protection and 
controls settings to allow for voltage ride through during system 
disturbances (as discussed above in Section III.B.4.b. Voltage Ride 
Through). We propose to direct NERC to submit to the Commission for 
approval one or more new or modified Reliability Standards that would 
require registered IBR generator owners and registered IBR generator 
operators to use appropriate and coordinated registered IBR protection 
and controls settings that will allow for voltage ride through during 
system disturbances and would permit registered IBR tripping only when 
necessary to protect the registered IBR equipment. Under this proposal, 
any new or modified Reliability Standard should require generator 
owners of registered IBR facilities to ensure that they prohibit 
momentary cessation in the no-trip zone during disturbances.\176\
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    \176\ We note that Reliability Standard PRC-024-3, Attachments 1 
and 2 clarify that the area outside the No Trip Zone is not a Must 
Trip Zone.
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    95. We are aware that certain registered IBRs currently in 
operation may not be able to meet the requirements proposed above. 
Therefore, we propose to direct NERC to require transmission planners 
and operators to implement mitigation activities that may be needed to 
address any reliability impact to the Bulk-Power System posed by these 
existing facilities. We believe that planners and operators should be 
able to accommodate this limited number of affected existing registered 
IBRs, and we expect that the technology of newer IBRs will not require 
such accommodation.
3. Post-Disturbance IBR Ramp Rate Interactions
    96. We preliminarily find that the current Reliability Standards do 
not sufficiently address registered IBR post-disturbance ramp rates 
following momentary cessation such that Bulk-Power System transient and 
frequency stability is supported during the system disturbances.\177\ 
We propose to direct NERC to submit to the Commission for approval one 
or more new or modified Reliability Standards that would require 
registered IBR post-disturbance ramp rate not to be restricted or to 
artificially interfere with the resource returning to pre-disturbance 
output level in a quick and stable manner after a Bulk-Power System 
fault event. Further, we propose generator owners communicate to the 
relevant planning coordinators, transmission planners, reliability 
coordinators, transmission operators, and balancing authorities the 
actual post-disturbance ramp rates and the ramp rates to meet expected 
dispatch levels (i.e., generation-load balance). The proposed 
Reliability Standards should account for the technical differences 
between registered IBRs and synchronous generation resources, such as 
registered IBRs' faster control capability to ramp power output down or 
up when capacity is available. We believe this proposal is consistent 
with the recommendations in various NERC reports discussed above.\178\
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    \177\ See Canyon 2 Fire Event Report at 9.
    \178\ See, e.g., id. (explaining that impeded ramp rates need to 
be ``remediated to ensure [Bulk-Power System] transient and 
frequency stability''); Blue Cut Fire Event Report at 15 (observing 
that during the Blue Cut Fire Event, some inverters that went into 
momentary cessation mode returned to pre-disturbance levels at a 
slow ramp rate).
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4. Phase Lock Loop Synchronization
    97. We preliminarily find that the current Reliability Standards do 
not require that all generation resources maintain voltage phase angle 
synchronization with the Bulk-Power System grid voltage during a system 
disturbance (as discussed in above Section III.B.4.d. Phase Lock Loop 
Synchronization). In other words, the current Reliability Standards do 
not adequately address registered IBR's momentary loss of synchronism 
caused by phase jumps during Bulk-Power System disturbance events. This 
results in protective action to open the inverter primary circuit 
breaker (i.e., phase lock loop loss of synchronism). We propose to 
direct NERC to submit to the Commission for approval one or more new or 
modified Reliability Standards that would require registered IBRs to 
ride through any conditions not addressed by the proposed Reliability 
Standards that address frequency or voltage ride through phase lock 
loop loss of synchronism. We note that NERC reported that phase lock 
loop loss of synchronism was a large contributor to the reduction of 
solar PV output during IBR related Bulk-Power System disturbance events 
that resulted in the unexpected loss of resources placing additional 
reliability risk on the Bulk-Power System.\179\ We believe this 
proposal is consistent with the IBR Interconnection Requirements 
Guideline and Canyon 2 Fire Event Report recommendations. The proposed 
Reliability Standards should require registered IBRs to ride through 
momentary loss of synchronism during Bulk-Power System disturbances and 
require registered IBRs to continue to inject current into the Bulk-
Power System at pre-disturbance levels during a disturbance.
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    \179\ See Section III.B.4.d.
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V. Information Collection Statement

    98. This NOPR proposes to direct the ERO to develop and submit to 
the Commission for approval one or more new or modified Reliability 
Standards and submit a compliance filing that includes a standards 
development plan for the new or modified reliability standards that 
address IBRs. The Paperwork Reduction Act (PRA) requires each federal 
agency to seek and obtain OMB approval before undertaking a collection 
of information directed to ten or more persons or contained in a rule 
of general applicability. Reliability Standards Development as 
described in FERC-725 covers standards development initiated by NERC, 
the Regional Entities, and industry, as well as standards the 
Commission may direct NERC to develop or modify.
    99. The proposal to direct NERC to develop new, or to modify 
existing, Reliability Standards (and the corresponding burden) are 
covered by, and already included in, the existing OMB-approved 
information collection FERC-725 (Certification of Electric Reliability 
Organization; Procedures for Electric Reliability Standards; OMB 
Control No. 1902-0225), under Reliability Standards Development.\180\ 
The reporting requirements in FERC-725 include the ERO's overall 
responsibility for developing Reliability Standards.
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    \180\ Reliability Standards Development as described in FERC-725 
covers standards development initiated by NERC, the Regional 
Entities, and industry, as well as standards the Commission may 
direct NERC to develop or modify.
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     Necessity of the Information: The proposed directive to 
the ERO to develop and submit to the Commission for approval one or 
more new or modified Reliability Standards, if adopted, would implement 
the Congressional mandate of the Energy Policy Act of 2005 to develop 
mandatory and enforceable Reliability Standards to better ensure the 
reliability of the nation's Bulk-Power System.

[[Page 74561]]

Specifically, the proposal would ensure that the ERO develops and 
submits for approval new or modified Reliability Standards that would 
require certain facilities to operate in support of the reliable 
operation of the Bulk-Power System.
     Internal review: The Commission has reviewed the proposed 
directive that the ERO revise its current Reliability Standards and 
determined that the proposal is necessary to meet the statutory 
provisions of the FPA requiring the Commission to ensure the 
reliability of the Bulk-Power System.
    100. Interested persons may obtain information on the reporting 
requirements by contacting: Federal Energy Regulatory Commission, 888 
First Street NE, Washington, DC 20426 [Attention: Ellen Brown, Office 
of the Executive Director, email: [email protected], Phone: (202) 
502-8663, fax: (202) 273-0873]. Comments on the requirements of this 
rule may also be sent to the Office of Information and Regulatory 
Affairs, Office of Management and Budget, Washington, DC 20503 
[Attention: Desk Officer for the Federal Energy Regulatory Commission]. 
For security reasons, comments should be sent by email to OMB at 
[email protected]. Please reference OMB Control No. 1902-
0225, FERC-725 and the docket number of this proposed rulemaking in 
your submission.

VI. Environmental Assessment

    101. The Commission is required to prepare an Environmental 
Assessment or an Environmental Impact Statement for any action that may 
have a significant adverse effect on the human environment.\181\ The 
Commission has categorically excluded certain actions from this 
requirement as not having a significant effect on the human 
environment. Included in the exclusion are rules that are clarifying, 
corrective, or procedural or that do not substantially change the 
effect of the regulations being amended.\182\ The actions proposed here 
fall within this categorical exclusion in the Commission's regulations.
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    \181\ Reguls. Implementing the Nat'l Env't Pol'y Act of 1969, 
Order No. 486, 52 FR 47897 (Dec. 17, 1987), FERC Stats. & Regs., ] 
30,783 (1987) (cross-referenced at 41 FERC ] 61,284).
    \182\ 18 CFR 380.4(a)(2)(ii).
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VII. Regulatory Flexibility Act Certification

    102. The Regulatory Flexibility Act of 1980 (RFA) \183\ generally 
requires a description and analysis of proposed rules that will have 
significant economic impact on a substantial number of small entities. 
By only proposing to direct NERC, the Commission-certified ERO, to 
develop modifications to Reliability Standards, this NOPR will not have 
a significant or substantial impact on entities other than NERC. The 
ERO develops and files with the Commission for approval Reliability 
Standards affecting the Bulk-Power System, which represents: (a) a 
total electricity demand of 830 GW (830,000 MW) and (b) more than $1 
trillion worth of assets. Therefore, the Commission certifies that this 
NOPR will not have a significant economic impact on a substantial 
number of small entities.
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    \183\ 5 U.S.C. 601-612.
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    103. Any Reliability Standards proposed by NERC in compliance with 
this rulemaking will be considered by the Commission in future 
proceedings. As part of any future proceedings, the Commission will 
make determinations pertaining to the Regulatory Flexibility Act based 
on the content of the Reliability Standards proposed by NERC.

VIII. Comment Procedures

    104. The Commission invites interested persons to submit comments 
on the matters and issues proposed in this notice to be adopted, 
including any related matters or alternative proposals that commenters 
may wish to discuss. Comments are due February 6, 2023 and Reply 
Comments are due March 6, 2023. Comments must refer to Docket No. RM22-
12-000, and must include the commenter's name, the organization they 
represent, if applicable, and their address in their comments.
    105. The Commission encourages comments to be filed electronically 
via the eFiling link on the Commission's website at https://www.ferc.gov. The Commission accepts most standard word processing 
formats. Documents created electronically using word processing 
software should be filed in native applications or print-to-PDF format 
and not in a scanned format. Commenters filing electronically do not 
need to make a paper filing.
    106. Commenters that are not able to file comments electronically 
must submit an original of their comments either by mail through the 
United States Postal Service to: the Secretary of the Commission, 
Federal Energy Regulatory Commission, 888 First Street NE, Washington, 
DC 20426,\184\ or by any other method of delivery, including hand 
delivery, to the Federal Energy Regulatory Commission, 12225 Wilkins 
Avenue, Rockville, Maryland 20852.\185\
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    \184\ 18 CFR 385.2001(a)(1)(i).
    \185\ 18 CFR 385.2001(a)(1)(ii).
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    107. All comments will be placed in the Commission's public files 
and may be viewed, printed, or downloaded remotely as described in the 
Document Availability section below. Commenters on this proposal are 
not required to serve copies of their comments on other commenters.

IX. Document Availability

    108. In addition to publishing the full text of this document in 
the Federal Register, the Commission provides all interested persons an 
opportunity to view and/or print the contents of this document via the 
internet through the Commission's Home Page (https://www.ferc.gov). At 
this time, the Commission has suspended access to the Commission's 
Public Reference Room due to the President's March 13, 2020 
proclamation declaring a National Emergency concerning the Novel 
Coronavirus Disease (COVID-19).
    109. From the Commission's Home Page on the internet, this 
information is available on eLibrary. The full text of this document is 
available on eLibrary in PDF and Microsoft Word format for viewing, 
printing, and/or downloading. To access this document in eLibrary, type 
the docket number excluding the last three digits of this document in 
the docket number field.
    110. User assistance is available for eLibrary and the Commission's 
website during normal business hours from the Commission's Online 
Support at 202-502-6652 (toll free at 1-866-208-3676) or email at 
[email protected], or the Public Reference Room at (202) 502-
8371, TTY (202)502-8659. Email the Public Reference Room at 
[email protected].

    By direction of the Commission. Commissioner Danly is concurring 
with a separate statement attached.

    Issued: November 17, 2022.
Debbie-Anne A. Reese,
Deputy Secretary.

    Note: The following appendix will not appear in the Federal 
Register

Appendix A

NERC IBR Resources Cited in the NOPR

NERC Guidelines

    NERC Guidelines referenced in this NOPR are available here: 
https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx.
    NERC, Reliability Guideline: BPS-Connected Inverter-Based 
Resource Performance (Sept. 2018), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf (IBR Performance 
Guideline).

[[Page 74562]]

    NERC, Reliability Guideline: Improvements to Interconnection 
Requirements for BPS-Connected Inverter-Based Resources (Sept. 
2019), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf (IBR Interconnection Requirements Guideline).
    NERC, Reliability Guideline: Parameterization of the DER A 
Model, (Sept. 2019),  https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf.
    NERC, Reliability Guideline: DER Data Collection for Modeling in 
Transmission Planning Studies, (Sept. 2020), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf (IBR-DER 
Data Collection Guideline).
    NERC, Reliability Guideline: Performance, Modeling, and 
Simulations of BPS-Connected Battery Energy Storage Systems and 
Hybrid Power Plants (Mar. 2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf 
(BESS Performance Modeling Guideline).

NERC White Papers

    IRPTF white papers referenced in this NOPR are available here: 
https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx.
    NERC, A Concept Paper on Essential Reliability Services that 
Characterizes Bulk Power System Reliability (Oct. 2014), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf (Essential Reliability Services Concept 
Paper).
    NERC, Resource Loss Protection Criteria Assessment Whitepaper 
(Feb. 2018),  https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf (Resource Loss Protection Whitepaper).
    NERC, Fast Frequency Response Concepts and Bulk Power System 
Reliability Needs (Mar. 2020),  https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf (Fast Frequency Response White Paper).
    NERC, IRPTF Review of NERC Reliability Standards White Paper 
(Mar. 2020),  https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf 
(Reliability Standards Review White Paper).
    NERC, San Fernando Disturbance Follow-Up White Paper (June 
2021),  https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20(003).pdf (San 
Fernando Disturbance White Paper).
    NERC, Utilizing the Excess Capability of BPS-Connected Inverter-
Based Resources for Frequency Support (Sept. 2021),  https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_IBR_Hybrid_Plant_Frequency_Response.pdf (Frequency 
Support White Paper).
    NERC, Odessa Disturbance Follow-up White Paper (Oct. 2021),  
https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf (Odessa Disturbance 
White Paper).

NERC Reports

    NERC, 2013 Long-Term Reliability Assessment (Dec. 2013),  
https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf (2013 LTRA Report).
    NERC, Distributed Energy Resources: Connection Modeling and 
Reliability Considerations (Feb. 2017),  https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf (NERC DER Report).
    NERC, 2020 Long Term Reliability Assessment Report (Dec. 2020),  
https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf (2020 LTRA Report).
    NERC, 2021 Long Term Reliability Assessment Report (Dec. 2021), 
https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf (2021 LTRA Report).

NERC Technical Reports

    NERC technical reports referenced in this NOPR are available 
here: https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx.
    NERC, Technical Report, BPS-Connected Inverter-Based Resource 
Modeling and Studies (May 2020),  https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_IBR_Modeling_and_Studies_Report.pdf (Modeling and Studies 
Report).
    NERC and WECC, WECC Base Case Review: Inverter-Based Resources 
(Aug. 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf (Western Interconnection (WI) Base 
Case IBR Review).

NERC Major Event Reports

    NERC event reports referenced in this NOPR are available here: 
https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx.
    NERC, 1,200 MW Fault Induced Solar Photovoltaic Resource 
Interruption Disturbance Report (June 2017), https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf (Blue Cut Fire Event Report) (covering the Blue Cut Fire event 
(August 16, 2016)).
    NERC and WECC, 900 MW Fault Induced Solar Photovoltaic Resource 
Interruption Disturbance Report (Feb. 2018), https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf (Canyon 2 Fire Event Report) (covering the Canyon 2 
Fire event (October 9, 2017)).
    NERC and WECC, April and May 2018 Fault Induced Solar 
Photovoltaic Resource Interruption Disturbances Report (Jan. 2019), 
https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf (Angeles Forest and 
Palmdale Roost Events Report) (covering the Angeles Forest (April 
20, 2018) and Palmdale Roost (May 11, 2018) events)/
    NERC and WECC, San Fernando Disturbance, (Nov. 2020), https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf 
(San Fernando Disturbance Report) (covering the San Fernando event 
(July 7, 2020)).
    NERC and Texas RE, Odessa Disturbance (Sept. 2021) https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf 
(Odessa Disturbance Report) (covering events in Odessa, Texas on May 
9, 2021 and June 26, 2021).
    NERC and WECC, Multiple Solar PV Disturbances in CAISO (April 
2022), https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf (2021 Solar PV 
Disturbances Report) (covering four events: Victorville (June 24, 
2021); Tumbleweed (July 4, 2021); Windhub (July 28, 2021); and Lytle 
Creek (August 26, 2021)).
    NERC and Texas RE, March 2022 Panhandle Wind Disturbance Report 
(August 2022),  https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf (Panhandle Report) (covering 
the Texas Panhandle event (March 22, 2022)).

NERC Alerts

    NERC Alerts referenced in this NOPR are available here: https://www.nerc.com/pa/rrm/bpsa/Pages/Alerts.aspx.
    NERC, Industry Recommendation: Loss of Solar Resources during 
Transmission Disturbances due to Inverter Settings (June 2017),  
https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20Loss%20of%20Solar%20Resources%20during%20Transmission%20Disturbance.pdf (Loss of Solar Resources Alert I).
    NERC, Industry Recommendation: Loss of Solar Resources during 
Transmission Disturbances due to Inverter Settings--II (May 2018), 
https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf (Loss of Solar Resources Alert II).

Other NERC Resources

    NERC, Reliability Assessment and Performance Analysis Department 
Modeling Assessments, https://www.nerc.com/pa/RAPA/ModelAssessment/Pages/default.aspx.
    NERC Libraries of Standardized Powerflow Parameters and 
Standardized Dynamics Models version 1 (Oct. 2015), https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf (NERC 
Standardized Powerflow Parameters and Dynamics Models).
    NERC, Events Analysis Modeling Notification Recommended 
Practices for

[[Page 74563]]

Modeling Momentary Cessation Initial Distribution (Feb. 2018), 
https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf.
    NERC, ERO Event Analysis Process--Version 4.0 (Dec. 2019), 
https://www.nerc.com/pa/rrm/ea/ERO_EAP_Documents%20DL/ERO_EAP_v4.0_final.pdf.
    NERC, Case Quality Metrics Annual Interconnection-wide Model 
Assessment, (Oct. 2021),  https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf.
    NERC, Informational Filing of Reliability Standards Development 
Plan 2022-2024, Docket No. RM05-17-000, et al., Attachment A, 
Reliability Standards Development Plan 2022-2024 (filed Nov. 30, 
2021) (NERC 2022-2024 Reliability Standards Development Plan).
    NERC, Inverter-Based Resource Strategy: Ensuring Reliability of 
the Bulk Power System with Increased Levels of BPS-Connected IBRs 
(Sept. 2022), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf (NERC IBR Strategy).

United States of America

Federal Energy Regulatory Commission

Reliability Standards to Address Inverter-Based Resources
Docket No. RM22-12-000

(Issued November 17, 2022)
    DANLY, Commissioner, concurring:
    1. I concur in today's order.\1\ I remain gravely concerned about 
the North American Electric Reliability Corporation's (NERC) inability 
to act swiftly and nimbly in response to emerging risks that threaten 
the reliability of the Bulk-Power System (BPS). This is due in no small 
part to the statutory framework of Federal Power Act (FPA) section 
215.\2\ According to NERC's Inverter-Based Resource (IBR) Strategy 
document,\3\ ``[t]he [Electric Reliability Organization (ERO)] 
Enterprise has analyzed numerous widespread IBR loss events and 
identified many systemic performance issues with the inverter-based 
fleet over the past six years.'' \4\ NERC explains that ``[t]he 
disturbance reports, alerts, guidelines, and other deliverables 
developed by the ERO thus far have highlighted that abnormal IBR 
performance issues pose a significant risk to BPS reliability.'' \5\ 
Our actions today in this and another proceeding \6\ propose firm 
deadlines by which NERC must act to register and hold IBR entities 
accountable for failure to comply with mandatory and enforceable 
Reliability Standards.
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    \1\ Reliability Standards to Address Inverter-Based Resources, 
181 FERC ] 61,125 (2022).
    \2\ 16 U.S.C. 824o.
    \3\ NERC, Inverter-Based Resource Strategy: Ensuring Reliability 
of the Bulk Power System with Increased Levels of BPS-Connected IBRs 
(Issued Sep. 14, 2022), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf.
    \4\ Id. at 3.
    \5\ Id. at 5.
    \6\ Registration of Inverter-based Resources, 181 FERC ] 61,124 
(2022).
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    2. Better late than never, I suppose. Nevertheless, it could be at 
least four years before certain of the IBR entities are registered and 
another five years before the full suite of contemplated requirements 
are mandatory and enforceable. So, it will be about ten or eleven years 
after the significant reliability risk was definitively identified that 
we will have required registration and Reliability Standards in place. 
The reliability consequences that attend the rapid deployment of an 
unprecedented number of IBRs are, at this point, unarguable. As NERC's 
President and CEO explained last week: ``the pace of the transformation 
of the electric system needs to be managed and that transition needs to 
occur in an orderly way.'' \7\ Mandatory reliability standards must be 
implemented as quickly as possible to ensure the reliable operation of 
the BPS. We at FERC are responsible for the reliability of the BPS 
under FPA section 215. I fear we may be taking too long to address 
reliability challenges that urgently need our attention.
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    \7\ Statement of James B. Robb, Annual Commissioner-led 
Reliability Technical Conference (Nov. 10, 2022), https://www.ferc.gov/news-events/events/annual-commissioner-led-reliability-technical-conference-11102022.
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    For these reasons, I respectfully concur.

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James P. Danly,
Commissioner.

[FR Doc. 2022-25599 Filed 12-5-22; 8:45 am]
BILLING CODE 6717-01-P