Building Energy Standards Program: Preliminary Determination Regarding Energy Efficiency Improvements in the Energy Standard for Buildings, Except Low-Rise Residential Buildings, ANSI/ASHRAE/IESNA Standard 90.1-2007, 54117-54131 [2010-22060]

Agencies

• DEPARTMENT OF ENERGY

[Federal Register Volume 75, Number 171 (Friday, September 3, 2010)]
[Notices]
[Pages 54117-54131]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-22060]


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DEPARTMENT OF ENERGY

 [Docket No. EERE-2006-BC-0132]
RIN 1904-AC18


Building Energy Standards Program: Preliminary Determination 
Regarding Energy Efficiency Improvements in the Energy Standard for 
Buildings, Except Low-Rise Residential Buildings, ANSI/ASHRAE/IESNA 
Standard 90.1-2007

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy

ACTION: Notice of preliminary determination.

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SUMMARY: The Department of Energy (DOE) has preliminarily determined 
that the 2007 edition of the Energy Standard for Buildings, Except Low-
Rise Residential Buildings, American National Standards Institute 
(ANSI)/American Society of Heating, Refrigerating and Air-Conditioning 
Engineers (ASHRAE) Illuminating Engineering Society of North America 
(IESNA) Standard 90.1-2007, (Standard 90.1-2007) would achieve greater 
energy efficiency in buildings subject to the code, than the 2004 
edition (Standard 90.1-2004 or the 2004 edition). Also, DOE has 
preliminarily determined that the quantitative analysis of the energy 
consumption of buildings built to Standard 90.1-2007, as compared with 
buildings built to Standard 90.1-2004, indicates national source energy 
savings of approximately 3.7 percent of commercial building energy 
consumption. Additionally, DOE has preliminarily determined site energy 
savings are estimated to be approximately 4.4 percent. If these 
determinations are finalized, States would be required to certify that 
they have reviewed the provisions of their commercial building code 
regarding energy efficiency, and as necessary, updated their code to 
meet or exceed Standard 90.1-2007. Additionally, this Notice provides 
guidance to States on Certifications, and Requests for Extensions of 
Deadlines for Certification Statements, should the preliminary 
determination by adopted as final.

DATES: Comments on the preliminary determination must be provided by 
October 4, 2010.

ADDRESSES: You may submit comments, identified by any of the following 
methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments.
     E-mail: ronald.majette@ee.doe.gov. Include RIN 1904-AC18 
in the subject line of the message.
     Postal Mail: Mr. Ronald B. Majette, U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, Forrestal 
Building, Mail Station EE-2J, 1000 Independence Avenue, SW., 
Washington, DC 20585-0121, Please submit one signed paper original.
     Hand Delivery/Courier: Mr. Ronald B. Majette, U.S. 
Department of Energy, Building Technologies Program, Room 6003, 1000 
Independence Avenue, SW., Washington, DC 20585-0121.
    Instructions: All submissions must include the agency name, 
Department of Energy, and docket number, EERE-2006-BC-0132, or 
Regulatory Information Number (RIN), 1904-AC18, for this rulemaking.

FOR FURTHER INFORMATION CONTACT: Mr. Ronald B. Majette, U.S. Department 
of Energy, Office of Energy Efficiency and Renewable Energy, Forrestal 
Building, Mail Station EE-2J, 1000 Independence Avenue, SW., 
Washington, DC 20585-0121, 202-586-7935. For legal issues contact 
Kavita Patel, U.S. Department of Energy, Office of the General Counsel, 
Forrestal Building, GC-71, 1000 Independence Avenue, SW., Washington, 
DC 20585, (202) 586-0669, e-mail: Kavita.Patel@hq.doe.gov.

SUPPLEMENTARY INFORMATION:
I. Introduction
    A. Statutory Requirements
    B. Background
    1. Publication of Standard 90.1-2007
    2. Analysis Methodology
    3. DOE Response to Comments on Previous Analysis
    C. Summary of the Comparative Analysis
    1. Quantitative Analysis
    2. Detailed Textual Analysis
    D. Preliminary Determination Statement
II. Results of Quantitative Analysis
III. Discussion of Detailed Textual Analysis
IV. Filing Certification Statements With DOE
    A. Review and Update
    B. Certification
    C. Requests for Extensions To Certify
V. Regulatory Analysis
    A. Review Under Executive Order 12866
    B. Review Under the Regulatory Flexibility Act
    C. Review Under the National Environmental Policy Act of 1969
    D. Review Under Executive Order 13132, ``Federalism''
    E. Review Under the Unfunded Mandates Reform Act of 1995
    F. Review Under the Treasury and General Government 
Appropriations Act of 1999
    G. Review Under the Treasury and General Government 
Appropriations Act of 2001
    H. Review Under Executive Order 13211
    I. Review Under Executive Order 13175
VI. Public Participation
VII. Approval of the Office of the Secretary

I. Introduction

A. Statutory Requirements

    Title III of the Energy Conservation and Production Act, as amended 
(ECPA), establishes requirements for the Building Energy Efficiency 
Standards Program. (42 U.S.C. 6831 et seq.) Section 304(b), as amended, 
of ECPA provides that whenever the ANSI/ASHRAE/IESNA Standard 90.1-1989 
(Standard 90.1-1989 or 1989 edition), or any successor to that code, is 
revised, the Secretary must make a determination, not later than 12 
months after such revision, whether the revised code would improve 
energy efficiency in commercial buildings and must publish notice of 
such determination in the Federal Register. (42 U.S.C. 6833 (b)(2)(A)) 
The Secretary may determine that the revision of Standard 90.1-1989 or 
any successor thereof, improves the level of energy efficiency in 
commercial buildings. If so, then not later than two years after the 
date of the publication of such affirmative determination, each State 
is required to certify that it has reviewed and updated the provisions 
of its commercial building code regarding energy efficiency with 
respect to the revised or successor code. (42 U.S.C. 6833(b)(2)(B)(i)) 
The State must include in its certification a demonstration that the 
provisions of its commercial building code, regarding energy 
efficiency, meet or exceed the revised standard. (42 U.S.C. 
6833(b)(2)(B)(i))
    If the Secretary makes a determination that the revised standard 
will not improve energy efficiency in commercial buildings, State 
commercial codes shall meet or exceed the last revised standard for 
which the Secretary has made a positive determination. (42 U.S.C. 
6833(b)(2)(B)(ii)). On December 30, 2008, the Secretary published a 
determination in the Federal Register updating the reference code to 
Standard 90.1-2004. 73 FR 79868.
    ECPA also requires the Secretary to permit extensions of the 
deadlines for the State certification if a State can demonstrate that 
it has made a good faith effort to comply with the requirements of 
Section 304(c) of ECPA and that it has made significant progress in 
doing so. (42 U.S.C. 6833(c))

[[Page 54118]]

B. Background

1. Publication of Standard 90.1-2007
    The American Society of Heating, Refrigerating and Air-Conditioning 
Engineers (ASHRAE) and the Illuminating Engineering Society of North 
America (IESNA) approved the publication of the 2007 edition of Energy 
Standard for Buildings Except Low-rise Residential Buildings, in 
December 2007.
    The Standard was developed under American National Standards 
Institute approved consensus standard procedures. Standard 90.1 is 
under continuous maintenance by a Standing Standard Project Committee 
(SSPC) for which the ASHRAE Standard Committee has established a 
documented program for regular publication of addenda or revisions, 
including procedures for timely, documented, consensus action on 
requests for change to any part of the standard. The American National 
Standards Institute (ANSI) approves addenda prior to their publication 
by ASHRAE and IESNA and therefore prior to their inclusion in a new 
version of Standard 90.1. ANSI approved the final addendum for 
inclusion in Standard 90.1-2007 on December 18, 2007. The 2007 edition 
was published in December 2007.
2. Analysis Methodology
    In arriving at a preliminary determination, the DOE first reviewed 
all significant changes between the 2004 edition and the 2007 edition 
of Standard 90.1. Standard 90.1 is complex and covers a broad spectrum 
of the energy related components and systems in buildings ranging from 
simple storage buildings to complex hospitals and laboratories. The 
size of buildings addressed range from those smaller than single family 
homes to the largest buildings in the world. The approach to 
development of the standard used in the 2007 edition was not changed 
from that used for the 2004 edition, with no changes to the scope or 
the way components are defined. We preliminarily determined that 
because no significant changes were made to the structure, scope, or 
component definitions of Standard 90.1-2004, a similar methodology used 
for the analysis of Standard 90.1-2004 could be utilized for the 
analysis of Standard 90.1-2007, consisting of a qualitative comparison 
of the textual changes to requirements in Standard 90.1-2007 from 
Standard 90.1-2004, and a quantitative estimate of the energy savings 
developed from whole building simulations of a standard set of 
buildings constructed to both Standards over a range of U.S. climates. 
DOE chose to modify several details of how the quantitative analysis 
would be done, including changes in the simulation tool used, the 
building models, and the procedure and data for weighting of results by 
building type and climate. DOE held a public workshop on February 18, 
2009 to provide for public comment on the proposed analysis 
methodology. DOE provided notice of the workshop in the Federal 
Register (74 FR 4169; Jan. 23, 2009) in which it outlined changes in 
the methodology from previous determinations and identified ten key 
issues for which it requested stakeholder input. These issues were:
    (1) Specific reductions in stringency in Standard 90.1-2007 that 
DOE should be made aware of and that have been identified by 
stakeholders.
    (2) Specific changes in scope between Standard 90.1-2004 and 
Standard 90.1-2007 and how DOE should interpret expansions of scope in 
its determination.
    (3) DOE's proposed approach to changes in referenced ventilation 
standards between Standard 90.1-2004 and Standard 90.1-2007.
    (4) DOE's proposed approach for addressing future effective dates 
for mechanical equipment requirements.
    (5) The frequency of use of alternative paths to compliance in 
building standards (e.g. space-by-space versus whole building lighting 
power allowances).
    (6) New non-residential building construction data (including Mid-
rise and High-rise residential) by State or census division and 
building type.
    (7) Data to quantify the impact of Standard 90.1 on additions and 
renovations to existing buildings.
    (8) The relative prevalence of the semi-heated building envelope 
subcategory in the building types proposed for analysis (e.g. 
warehouses).
    (9) The relative importance of the Mid- and High-rise residential 
sector in DOE's determination and data for developing weighting factors 
for this sector.
    (10) Data describing the relative frequency of use of alternative 
paths to compliance.
    DOE only received stakeholder input peripherally related to one of 
these key issues, that of the relative importance of mid- to high-rise 
residential building and their construction. However, DOE received 
input on several other issues of concern to stakeholders.
3. DOE Response to Comments on Previous Analysis
    DOE sought comment on its general approach to the preliminary 
determination analysis and during the public meeting outlined the 
proposed approach and responded to questions and to comments received. 
DOE reviewed the comments and data submitted regarding issues raised in 
the proposed methodology for the quantitative analysis. The more 
significant comments are discussed below. DOE received comments in four 
general areas regarding the determination analysis methodology: The 
treatment of equipment efficiency improvements, characteristics of 
multi-family buildings, climates used in the quantitative analysis, and 
how DOE addresses the cost-effectiveness of requirements. DOE received 
other comments relating to how the determination results were to be 
used.
    DOE's proposed quantitative analysis methodology includes any 
equipment efficiency improvements mandated by Federal equipment 
efficiency standards, either established by DOE or by legislation but 
not initiated by addenda to ASHRAE 90.1-2004, in the ASHRAE 90.1-2004 
baseline. The purpose for this is to prevent inclusion in the 
quantitative analysis of energy savings that would occur in new 
building construction (due to these mandated equipment efficiency 
improvements) regardless of the use of Standard 90.1-2004 or Standard 
90.1-2007 as the basis for State building codes. This is consistent 
with the approach used in previous DOE determinations.
    The National Multi Housing Council (NMHC) commented that DOE's 
approach would seem to miss an important energy savings feature and 
that the published standard does have a list of equipment efficiencies 
that should be the base for the calculations. NMHC commented that 
taking this into account would seem to be more important given the 
emphasis to improve the efficiency of the standard by a certain 
percentage. Also, NMHC commented that there is a time lag between when 
equipment improvements are adopted by the standards and when DOE 
publishes these as requirements. (NMHC, Public Meeting Transcript, pp. 
38, 40-41)
    DOE does not use the determination methodology to ascertain whether 
the standard has met a minimum percentage improvement and is instead 
focused on estimating whether the adoption of the revised standard as 
the basis of State building codes would result in energy savings, as 
compared to the previous

[[Page 54119]]

version. With regard to the last statement, DOE's quantitative analysis 
methodology does include energy savings from improvements in equipment 
efficiency first initiated by ASHRAE 90.1 in part because these 
improvements can be requirements in building codes before they can be 
promulgated as Federal minimum equipment efficiency standards. After 
considering the statements of NMHC, DOE determined not to modify its 
proposed methodology.
    The Responsible Energy Codes Alliance (RECA) wanted clarification 
and assurance that DOE was not providing credit in the assessment of 
energy savings for any requirements in 90.1 that would in fact be 
preempted by existing Federal equipment efficiency standards and 
therefore could not be promulgated in State codes. (RECA, Public 
Meeting Transcript, pp. 43-45) DOE notes that there are no such 
requirements in ASHRAE Standard 90.1-2007 and that this concern does 
not exist for this preliminary determination.
    In its discussion on the number of climates, NMHC asked if DOE 
planned to reduce the number of simulation locations from those 
identified in the notice and encouraged DOE not to reduce the number of 
locations used for the quantitative analysis simulations. (NMHC, Public 
Meeting Transcript, p. 57) In response, DOE will use a single 
representative climate for each of the 15 U.S. climate zones identified 
in the ASHRAE Standard 90.1-2004 and ASHRAE Standard 90.1-2007 
documents. It did not reduce the number of climate zones being used in 
the quantitative analysis but rather increased this number when 
compared with previous determinations.
    In commenting on representativeness of the multi-family building 
models, the NMHC commented that wood-frame was the dominant 
construction type up to and including four stories. NMHC stated that 
above five stories, steel-frame construction is more common, but the 
percentage of the construction market represented by these taller 
buildings drops off considerably. NMHC suggested that for the mid-rise 
multi-family buildings, DOE could assume that wood-frame construction 
was representative of the market. NMHC noted a steel-frame building 
would be more representative of a high-rise construction (10 stories) 
and DOE could assume steel-frame for the high-rise multi-family 
building class. (NMHC, Public Meeting Transcript, p. 65) The American 
Forest & Paper Association (AF&PA) expressed concern that the 
quantitative analysis would not pick up on the fact that multi-family 
buildings are built out of wood-frame construction. (AF&PA, Public 
Meeting Transcript, p. 73) In response, DOE appreciates the information 
provided by the NMHC and points out that wood-frame construction does 
form the basis of the mid-rise apartment building model. DOE has not 
included a high-rise apartment building model into its quantitative 
analysis for the Standard 90.1-2007 determination.
    AF&PA expressed concern over how the results of a quantitative 
analysis are used by DOE and presented to the building community. In 
particular, AF&PA questioned why a quantitative analysis is being done 
by DOE, given the legislative charge to DOE regarding the 
determination. AF&PA stated that it appeared that doing a quantitative 
analysis may be going beyond what is required of DOE. Further, AF&PA 
stated that DOE believes that this comparison can be done with a 
qualitative analysis, but DOE is choosing to bring in a quantitative 
analysis that misses some very significant issues such as construction 
type and material choices. They stated that it seems that the DOE goal 
for 30 percent savings applies only to Federal buildings and questioned 
why DOE isn't looking at a typical pool of Federal buildings if it 
wants to do a quantitative analysis toward that goal. Finally, AF&PA 
stated that the results of a quantitative analysis would be a driving 
factor with the 90.1 committee, and that this would put further 
pressure on the committee to increase the stringency of wood-frame 
construction. (AF&PA, Public Meeting Transcript, pp. 69-74)
    In response, DOE notes that the preliminary determination on ASHRAE 
Standard 90.1-2007 is not related to the legislative goal of 30-percent 
improvement in Federal buildings. In addition, while DOE has signed a 
memorandum with ASHRAE to improve energy efficiency in commercial 
building codes (Memorandum of Understanding between the United States 
Department of Energy and the American Society of Heating, Refrigerating 
and Air-Conditioning Engineers, Inc. Signed July 2007), DOE does not 
consider the purpose of the preliminary determination to measure how 
far along a path building standards have progressed from ASHRAE 
Standard 90.1-2004. DOE does believe that a quantitative analysis of 
savings should be done alongside a qualitative analysis and has carried 
this through in past ASHRAE Standard 90.1 determinations. The 
quantitative analysis allows DOE to examine quantitatively multiple 
changes to Standard 90.1, with some reflecting improved efficiency, and 
others possibly reduced efficiency to determine in balance whether 
there has been an overall improvement in building efficiency. DOE does 
not intend for this preliminary determination to be used as a tool to 
measure progress toward a 30-percent improvement in commercial building 
energy codes beyond ASHRAE Standard 90.1-2004. In support of both the 
preliminary determination and ASHRAE-driven code improvement process, 
DOE and ASHRAE are relying on a sample set of commercial buildings 
(based on the DOE benchmark buildings developed for DOE's Net-Zero 
Energy Commercial Buildings Initiative and available at https://www1.eere.energy.gov/buildings/commercial_initiative/benchmark_models.html) for measuring improvement in commercial building 
efficiency. DOE is using versions of this same set of building models 
for both the preliminary determination quantitative analysis as well as 
in a separate project to track improvement in future updates to ASHRAE 
Standard 90.1. The versions used for this preliminary determination can 
be found at https://www.energycodes.gov/implement/determinations_90.1-2007.stm.
    Following up on AF&PA comments, ASHRAE commented that the Standard 
90.1 development process is done with consensus building following the 
ANSI process and is developed through a broad spectrum of 
representation. ASHRAE further commented that the 30-percent target 
that was reflected in a memorandum with DOE to improve efficiency in 
commercial buildings is a goal, not a mandate, since a mandate cannot 
be placed on a consensus body. (ASHRAE, Public Meeting Transcript, pp. 
81, 82)
    AF&PA also commented that the DOE analysis reflects a snapshot in 
time and does not consider changes that will occur in the marketplace. 
Further, AF&PA believed that there is a legislative charge for DOE to 
support the notion of cost-effectiveness and use of readily available 
technology. They asked if there is a way for DOE to become more engaged 
in how that aspect is driving changes in envelope energy performance. 
(AF&PA, Public Meeting Transcript, pp. 87-88) In response, DOE points 
out that the analysis used to set the envelope requirements for 
different construction assemblies had cost-effectiveness as its basis. 
However, the purpose of the preliminary determination analysis is not 
to investigate the validity of the development of ASHRAE Standard

[[Page 54120]]

90.1-2007 but to determine whether it reflects an increase in 
efficiency.
    AF&PA also asked if a description of the building models, in 
particular how infiltration is modeled, could be provided. (AF&PA, 
Public Meeting Transcript, pp. 93-94) DOE has included a description of 
the benchmark building models and how these were used in the 
quantitative analysis documentation published at https://www.energycodes.gov/implement/determinations_90.1-2007.stm.
    RECA commented that some States that will adopt the International 
Energy Conservation Code (IECC) for both residential and commercial 
building energy codes with the understanding that because ASHRAE is 
referenced by the IECC, they are essentially equivalent. RECA asked 
whether DOE has prepared any guidance for States to describe what is 
acceptable and whether this would be provided in the preliminary 
determination. (RECA, Public Meeting Transcript, pp. 111-112)
    Currently, DOE has not published any statements that a version of 
the IECC is equivalent in terms of energy savings to for ASHRAE 90.1 in 
the State code certification process. Each State's submittal with 
regard to certification of its energy code is dealt with on a case-by-
case basis. Further, the DOE commercial energy code certification 
requirements with regard to meeting or exceeding the efficiency of the 
most recent ASHRAE Standard 90.1 version for which a positive 
determination has been made are separate from the residential energy 
code certification requirements that reference the IECC. Some States 
may adopt the IECC and not adopt the commercial code requirements. For 
these reasons, DOE considers the commercial and residential building 
energy code certification by the States a separate process.
    As acknowledged in the previous analysis, DOE recognizes that, 
given the numerous assumptions required to simulate the potential 
impact of a new commercial building energy standard, reasonable minds 
could differ over both the specific building models employed and the 
assumptions used in those models. DOE also recognizes the cautions from 
AF&PA regarding the quantitative analysis and previous comments about 
the complexity of the problem.
    DOE recognizes that the methodology proposed for the quantitative 
analysis will be insufficient for determining an absolute 
quantification of energy savings estimates associated with using 
Standard 90.1-2007 (e.g., total quads of energy savings) and makes no 
such claim for the analysis on which this preliminary determination 
relies. DOE's quantitative analysis includes many of the changes 
brought about in Standard 90.1-2007 that can be modeled, but this 
quantitative analysis is not able to quantify accurately all the likely 
effects of the new standard. In particular, the degree to which the 
market may react to certain changes brought about following the 
adoption of a new building code, and the degree to which different 
requirements are currently being met or will be met in future 
construction, are exceedingly difficult to ascertain and would affect 
the absolute quantification of energy savings. However, DOE believes 
that the quantitative determination process outlined does provide a 
reasonable approach to establishing whether, in concert, the changes 
brought about by ASHRAE Standard 90.1-2007 will result in improved 
energy efficiency in buildings over ASHRAE Standard 90.1-2004.
    DOE continues to believe that the preliminary determination should 
rely on both quantitative and qualitative comparisons. While 
quantitative estimates of energy savings are indeed a much preferred 
method of comparison, it is not always possible to simulate or provide 
appropriate weighting to many features in Standard 90.1. Therefore, DOE 
will continue to note changes that individually or in net result in 
increased energy efficiency, even where they could not be accurately 
quantified. States can use this information when upgrading their energy 
codes.
    DOE continues to believe that the quantitative analysis should be 
based on the minimum requirements of each standard that reflect the 
minimum set of options available in new construction. In assessing the 
impact of those requirements, DOE also believes that assessment should 
be based on an estimate of typical construction practices. DOE believes 
that this has been done in the quantitative analysis.
    For this preliminary determination, DOE utilized 5 years of 
previous building construction data, as developed using proprietary 
F.W. Dodge building statistical data by building type and by location 
down to the county level and purchased by DOE, to develop weighting 
factors to weight the building simulation results. (A summary of the 
data is available in a PNNL report--PNNL-19116--Jarnagin and 
Bandyopodhyay, 2010, Weighting Factors for the Commercial Building 
Prototypes used in the Development of ANSI/ASHRAE/IESNA Standard 90.1-
2010 at https://www.pnl.gov/main/publications/external/technical_reports/PNNL-19116.pdf.) Past determinations have relied on new 
construction floor space growth estimates extracted from the Energy 
Information Administration's (EIA) National Energy Modeling System 
(NEMS) as the basis for weighting energy savings across building types 
and regions. DOE believes that for the purpose of this analysis the 
F.W. Dodge construction data provides better mapping of actual 
construction by region and building type than could be obtained using 
the EIA/NEMS data. In particular, the use of county-level construction 
data allowed DOE to develop building construction statistics directly 
reflecting construction in each of the ASHRAE climate regions, avoiding 
many assumptions on regional construction volume that would be 
necessary using the EIA/NEMS data.
    Consistent with the previous analysis, DOE compared versions of 
Standard 90.1 ``as a whole'' and did not issue determinations for 
individual addenda. DOE interprets the language in Section 304(b)(2) of 
ECPA to mean that when a comprehensive revision of the ASHRAE Standard 
is published (which in this case is ASHRAE Standard 90.1-2007), then 
that revised or successor standard triggers the Secretary's obligation 
to issue a determination as to whether the revised standard improves 
energy efficiency. This determination is made by comparing the revised 
or successor standard to the last predecessor standard. While the 
addenda process is part of the ongoing maintenance of the standard and 
thus continually modifies or revises the existing standard over time, 
it would be an unreasonable reading of the statute to categorize each 
addenda in this maintenance process as a ``revised or successor 
standard'' within the meaning of Section 304(b)(2) of ECPA, so as to 
require a determination by the Secretary. Such an interpretation of the 
statute would put an unreasonable burden both on the States and DOE. 
For the States, a determination by the Secretary requires some State 
action, and what is required depends upon whether the Secretary issues 
an affirmative or a negative determination. If the Secretary were 
required to issue a determination after each addenda was published, the 
States would be constantly required to change their codes. This would 
affect the stability and certainty of State commercial building codes.
    The statutory language in Section 304(b) of ECPA states that the 
Secretary is required to make a determination as to whether any 
successor standard to ASHRAE Standard 90.1-1989 will improve energy 
efficiency. (42 U.S.C. 6833(b)(2)(A)) The Secretary must publish a 
notice of this determination in

[[Page 54121]]

the Federal Register. The language does not require that DOE perform an 
independent economic analysis as part of the determination process. 
Section 304(b) of ECPA does not include any reference to language 
concerning economic justification.
    However, Congress did address consideration of the technological 
feasibility and cost effectiveness of the Voluntary Building Energy 
Codes. Section 307 of ECPA requires DOE to participate in the ASHRAE 
process and to assist in determining the cost effectiveness and 
technical feasibility of the ASHRAE standard. (42 U.S.C. 6836) It also 
requires DOE to periodically review the economic basis of the voluntary 
building energy codes and participate in the industry process for 
review and modification, including seeking adoption of all 
technologically feasible and economically justified energy efficiency 
measures. (42 U.S.C. 6836(b))
    Unlike Section 307 of ECPA (42 U.S.C. 6836), which specifically 
includes language concerning economic justification, Section 304 of 
ECPA does not include any reference to economic justification. ``It is 
generally presumed that Congress acts intentionally and purposefully 
where it includes particular language in one section of a statute but 
omits it in another section.'' Bates v. United States, 522 U.S. 23, 29-
30 (1997) (Citations omitted). Accordingly, the statutory scheme cannot 
be read to require an economic analysis as part of the determination 
process in Section 304(b) of ECPA.
    The fact that the Section 304 of ECPA determination process does 
not require the Secretary to perform an economic analysis does not 
diminish the importance that the ASHRAE standards be technologically 
feasible and economically justified. However, the statute addresses 
these issues by directing DOE to participate in the ASHRAE process 
itself.
    Accordingly, for all of these reasons, DOE has determined that it 
is not required to perform an economic analysis as part of its 
determination process in Section 304 of ECPA.
    A significant change in DOE's approach from previous determinations 
was the use of specific buildings, as representative of a typical 
building type, in the development of building energy use intensity 
(EUI), without the scaling approach used in previous determinations. 
While the scaling approach used previously provides an assessment of 
the impact of building changes over a broad range of building sizes, 
DOE determined that the benefits did not outweigh the complexity of 
this approach for the purpose of a yes/no determination. The 
availability of commercial benchmark building models in EnergyPlus for 
a wide variety of building types and typical sizes was deemed 
sufficient for the preliminary quantitative determination analysis of 
Standard 90.1-2007.
    One of the most significant commercial building end-uses regulated 
by energy codes and standards is lighting. For the preliminary 
quantitative analysis, each of DOE's building models have its internal 
lighting power density (LPD) determined using either the building area 
lighting compliance path or the space-by-space lighting compliance path 
from each ASHRAE Standard 90.1 edition. Building area LPDs are defined 
in ASHRAE Standard 90.1 as maximum lighting power allowance given in 
watts (W)/square foot (ft\2\), for specific building types and do not 
consider internal variation in the spaces used within a given building. 
In contrast, space-by-space LPDs are a specific lighting power 
allowance in W/ft\2\ for a given space type regardless of what building 
type it is in. Using the space-by-space method, the maximum allowed 
lighting power density for a given building is determined by summing up 
the product of the area fraction of each defined space-type within the 
building and the allowed lighting power within each space-type. The 
space-by-space method takes into account variation in the area devoted 
to different space types within a particular building. In addition, 
both Standard 90.1 editions allow for certain additional lighting power 
allowances when the space-by-space method is used.
    The building models used for the preliminary quantitative analysis 
are specific building designs, in most cases with specific spaces 
defined within the prototype and with different lighting schedules for 
each space in accordance with its expected use. DOE chose to use the 
space-by-space method to establish the overall lighting power within 
these prototypes. In the case of one prototype, the strip mall retail 
building, DOE also included lighting power to reflect the typical 
values for additional lighting power allowances that would be allowed 
as display lighting under Standard 90.1-2004 and Standard 90.1-2007, 
assuming the same display area in the prototype. For building 
prototypes where space type distinctions were not deemed as important 
or significant, the building area LPD numbers were used (e.g., office 
buildings).
    The use of the space-by-space lighting method is a deviation from 
previous ASHRAE Standard 90.1 determinations where less detailed 
building models were utilized in the quantitative analysis. However, 
since the base LPD values for either path did not change between 
Standard 90.1-2004 and Standard 90.1-2007 and the change in the 
additional lighting power allowance was small and considered for only 
one building type, the choice of compliance path was deemed not to 
affect significantly the determination of energy savings. For each 
building type, Table 1shows the lighting compliance path used for the 
quantitative analysis and the average LPD used in the building models. 
Once selected, the same compliance path was used for LPD assumptions in 
both Standard 90.1 editions being compared. For each building 
prototype, the ASHRAE Standard 90.1-2004 and 90.1-2007 building area 
LPDs are shown for comparison alongside the values used in the 
quantitative analysis.

                        Table 1--Internal Lighting Power Density Used in Building Models
----------------------------------------------------------------------------------------------------------------
                                                Lighting         Simulation lighting     Building area lighting
                             Building       compliance path     power densityW/ft\2\      power densityW/ft\2\
     Building type          prototype           used for     ---------------------------------------------------
                                            simulation model   90.1-2004    90.1-2007    90.1-2004    90.1-2007
----------------------------------------------------------------------------------------------------------------
Office................  Small Office.....  Building Area....        1.000        1.000          1.0          1.0
                        Medium Office....  Building Area....        1.000        1.000          1.0          1.0
                        Large Office.....  Building Area....        1.000        1.000          1.0          1.0
Retail................  Stand-Alone        Space-by-Space...        1.548        1.548          1.5          1.5
                         Retail.
                        Strip Mall.......  Space-by-Space...        1.645        1.568          1.5          1.5
Education.............  Primary School...  Space-by-Space...        1.188        1.188          1.2          1.2
                        Secondary School.  Space-by-Space...        1.134        1.134          1.2          1.2
Healthcare............  Outpatient Health  Space-by-Space...        1.094        1.094          1.0          1.0
                         Care.

[[Page 54122]]

 
                        Hospital.........  Space-by-Space...        1.119        1.119          1.2          1.2
Lodging...............  Small Hotel......  Space-by-Space...        0.968        0.968          1.0          1.0
                        Large Hotel......  Building Area....        1.000        1.000          1.0          1.0
Warehouse.............  Non-Refrigerated   Space-by-Space...        0.810        0.810          0.8          0.8
                         Warehouse.
Food Service..........  Fast Food          Space-by-Space...        1.650        1.650          1.4          1.4
                         Restaurant.
                        Sit-Down           Space-by-Space...        1.855        1.855          1.6          1.6
                         Restaurant.
Apartment.............  Mid-Rise           Space-by-Space...        0.402        0.402          0.7          0.7
                         Apartment.
----------------------------------------------------------------------------------------------------------------

    The building area LPDs are identical for both Standard 90.1 
versions. The space-by-space LPDs tabulated by space type are also 
identical in both Standards. However, in addition, under the space-by-
space compliance path are additional lighting power allowances provided 
for specific circumstances (primarily display lighting). Standard 90.1-
2004 and Standard 90.1-2007 both have additional lighting power 
allowances for decorative lighting and for retail display lighting to 
highlight merchandise. Standard 90.1-2004 also provides a small 
additional lighting power allowance for video display terminal 
lighting. This latter was removed in Standard 90.1-2007 and considered 
seldom used in practice. The additional lighting power for decorative 
lighting was not changed between standards. The additional lighting 
power allowance for retail display lighting was changed to use four 
specific merchandise categories described by lists of merchandise. Only 
two general merchandise categories were used in Standard 90.1-2004. DOE 
collected limited information on display areas in a small sample of 
retail buildings and made a conservative estimate that for the strip 
mall prototype, approximately 13 percent of the entire building area 
might qualify for the display lighting power allowances. DOE assumed 
that the additional lighting power allowance for that display area was 
reduced from an average of 2.75 W/ft2 (based on an average 
of the two additional lighting power display categories in Standard 
90.1-2004) to 2.15 W/ft2 (based on an average of the middle 
two additional lighting power display categories in Standard 90.1-
2007). This assumption resulted in a 4.6 percent reduction in whole 
building LPD for this prototype. DOE believes that this result is 
likely a conservative estimate of the energy savings from this 
additional lighting power change.
    The final space-by-space calculations used in the quantitative 
analysis yield LPDs that differ from the LPDs determined from the 
building area compliance paths. For all building models other than 
restaurants and the mid-rise apartment, the lighting power densities 
used are between 7 percent lower to 8 percent higher than LPD from the 
building area compliance path. The LPDs modeled for the two restaurant 
prototypes are 16 to 18 percent higher than the LPD from the building 
area compliance path in either standard, a direct result of the 
relative ratio of kitchen to dining areas used in these prototypes 
compared with that assumed in the development of the ASHRAE 90.1 
building area LPD values. All else being equal, the impact of higher 
LPD assumptions is to result in a somewhat greater cooling load and 
lower heating load in these prototypes.
    The building average LPD modeled for the mid-rise apartment 
prototype is 43 percent lower than the tabulated building area LPD 
value shown in both versions of Standard 90.1. However, the lighting 
section in both versions states that lighting in living units (i.e., 
apartments within multi-family housing) is not within the scope of 
Standard 90.1, implying that the building area method value should be 
applied only to common space within multi-family buildings and would 
not be suitable for the modeling of building lighting power. To 
generate the LPD for the mid-rise apartment building, DOE used the 
space-by-space LPD allowances in Standard 90.1. The mid-rise apartment 
prototype consists of two defined space types: Office-enclosed and 
corridors; and the individual apartment units. Standard 90.1 has space-
by-space LPDs for the office and corridor spaces. DOE assumed a value 
of 0.36 W/ft2 for the LPD inside the apartments based on the 
lighting power assumptions found in the DOE Residential Building 
America Research Benchmark.
    Identical lighting schedules were used for the Standard 90.1-2004 
and Standard 90.1-2007 building prototypes, as no addenda to Standard 
90.1-2004 affected the scheduled usage.
    In addition to the internal lighting power density, Standard 90.1 
has requirements for exterior lighting power. These requirements are 
identical between Standard 90.1-2004 and Standard 90.1-2007 and are 
based on the application of specific exterior lighting power densities 
allowances to defined exterior surfaces types (e.g., building entrances 
or parking areas). In order for the building prototypes to better 
reflect energy use in actual buildings, specific assumptions for the 
amount of these defined exterior surfaces present for each building 
prototype were developed from detailed building plan data. All exterior 
lighting was assumed to be controlled by astronomical time clock for 
the prototypes.
    Table 2 shows the exterior lighting power assumption, expressed in 
W/ft\2\ of building area.

              Table 2--Exterior Lighting Power for Both 90.1-2004 and 90.1-2007 Building Prototypes
----------------------------------------------------------------------------------------------------------------
                                                             Prototype exterior lighting power (normalized to W/
                                  Building      Prototype                ft2 of building floor area)
        Building type            prototype      floor area -----------------------------------------------------
                                                   ft2      Parking lot     Doors     Fa[ccedil]ade     Total
----------------------------------------------------------------------------------------------------------------
Office......................  Small Office...        5,502        0.243        0.039         0.015         0.297
                              Medium Office..       53,628        0.243        0.010         0.015         0.268
                              Large Office...      498,588        0.098        0.002         0.026         0.126

[[Page 54123]]

 
Retail......................  Stand-Alone           24,692        0.213        0.063         0.020         0.297
                               Retail.
                              Strip Mall.....       22,500        0.282        0.095         0.030         0.407
Education...................  Primary School.       73,959        0.030        0.039         0.004         0.073
                              Secondary            210,887        0.042        0.021         0.003         0.067
                               School.
Healthcare..................  Outpatient            40,946        0.304        0.042         0.007         0.353
                               Health Care.
                              Hospital.......      241,501        0.048        0.007         0.014         0.069
Lodging.....................  Small Hotel....       43,202        0.117        0.006         0.018         0.140
                              Large Hotel....      122,120        0.109        0.004         0.047         0.159
Warehouse...................  Non-                  52,045        0.058        0.090         0.003         0.151
                               Refrigerated
                               Warehouse.
Food Service................  Fast Food              2,501        0.607        0.024         0.065         0.697
                               Restaurant.
                              Sit-Down               5,502        0.607        0.027         0.037         0.672
                               Restaurant.
Apartment...................  Mid-Rise              33,741        0.127        0.000         0.011         0.138
                               Apartment.
----------------------------------------------------------------------------------------------------------------

    Because the exterior lighting power densities did not change 
between Standard 90.1-2004 and Standard 90.1-2007, the inclusion of 
exterior lighting does not affect DOE's determination of energy 
savings; however, as it affects the baseline building energy use, it 
does have an impact on the percentage savings calculated for each 
building type.
    DOE's preliminary quantitative determination was carried out using 
the EnergyPlus building simulation tool. EnergyPlus was selected for 
this determination for several reasons. First, DOE believes that the 
underlying calculation methods and the wide variety of systems 
available in EnergyPlus version 3.0, used for this preliminary 
determination, are sufficiently advanced over those in BLAST and DOE2 
to justify the use of EnergyPlus. Quoting from DOE's EnergyPlus Web 
site (https://apps1.eere.energy.gov/buildings/energyplus/), ``While 
originally based on the most popular features and capabilities of BLAST 
and DOE-2, EnergyPlus includes many innovative simulation capabilities 
such as time steps of less than an hour, modular systems and plant 
integrated with heat balance-based zone simulation, multi-zone air 
flow, thermal comfort, water use, natural ventilation, and photovoltaic 
systems''. Second, DOE had developed a set of commercial building 
prototypes in EnergyPlus that could reasonably form the basis of a 
national-scale simulation analysis. DOE has received and responded to 
much feedback from the ASHRAE Standard 90.1 simulation working group 
and other simulation experts on how to improve the representativeness 
of these building models. Finally, DOE believes that a critical mass of 
EnergyPlus users and sufficiently broad range of DOE contractor 
experience with the tools meant that models could be reviewed and 
results examined sufficiently for the purpose of the preliminary 
determination.

C. Summary of the Comparative Analysis

    DOE carried out both a broad quantitative analysis and a detailed 
textual analysis of the differences between the requirements and the 
stringencies in the 2004 and the 2007 editions of Standard 90.1.
1. Quantitative Analysis
    The quantitative comparison of ASHRAE Standard 90.1-2007 was 
carried out using whole-building energy simulations of buildings built 
to both ASHRAE Standard 90.1-2004 and ASHRAE Standard 90.1-2007. DOE 
simulated 15 representative building types in 15 U.S. climate 
locations, each climate location selected to be representative of one 
of the 15 U.S. climate zones used in the definition of building energy 
code criteria in ASHRAE Standard 90.1-2004 and Standard 90.1-2007. The 
simulations were developed using specific building prototypes based on 
the DOE commercial benchmark building models developed for DOE's Net-
Zero Energy Commercial Building Initiative.
    For each building prototype simulated in each climate the energy 
use intensities (EUI) by fuel type and by end-use were extracted. These 
EUIs by fuel type for each building were then weighted to national 
average EUI figures using weighting factors based on the relative 
square footage of construction represented by that prototype in each of 
the 15 climate regions. These weighting factors were based on 
commercial building construction starts data for a five year period 
from 2003 to 2007. The source of data was the McGraw-Hill Construction 
Projects Starts Database (MHC). The MHC database captures over 90% of 
new commercial construction in any given year and the collection 
process is independently monitored to ensure the coverage of most of 
the commercial construction in the U.S. The data is used by other 
federal agencies such as the U.S. Census Bureau, the Federal Reserve 
and the U.S. Department of Health and Human Services (HHS) for 
characterizing building construction in the U.S. For the purpose of 
developing construction weighting factors, the strength of this data 
lies in the number of samples, the characterization of each sample in 
terms of building end-use and size and number of stories, the frequency 
of data collection, and the detailed location data. In addition, the 
MHC database can be used to identify multi-family residential buildings 
that would be covered under ASHRAE Standard 90.1.
    DOE's prototypes reflect the use of two fuel types, electricity and 
natural gas. Using the weighting factors, DOE was able to preliminarily 
establish an estimate of the relative reduction in building energy use, 
as determined by a calculated reduction in weighted average site EUI 
for each building prototype. Site energy refers to the energy consumed 
at the building site. In a corresponding fashion, DOE was also able to 
calculate a reduction in terms of weighted average primary EUI and in 
terms of weighted average energy cost intensity (ECI) in $/sf of 
building floorspace. Primary energy as used here refers to the energy 
required to generate and deliver energy to the site. To estimate 
primary energy, all electrical energy use intensities were first 
converted to primary energy using a factor of 10,800 Btus primary 
energy per kWh (based on the 2009 estimated values reported in Table 2 
of the EIA Annual Energy Outlook, 2009, April 2009 release available at 
https://

[[Page 54124]]

www.eia.doe.gov/oiaf/aeo/). Natural Gas EUIs in the prototypes were 
converted to primary energy using a factor of 1.089 Btus primary energy 
per Btu of site natural gas use (based on the 2009 national energy use 
estimated shown in Table 2 of the AEO 2009). This natural gas source 
energy conversion factor was calculated by dividing the sum of all 
natural gas usage, including usage for natural gas field production, 
leases, plant fuel, and pipeline (compression) supply by delivered gas 
energy to the four primary energy sectors (residential, commercial, 
industrial, and transportation).
    To estimate the reduction in energy cost index, DOE relied on 
national average commercial building energy prices of $0.1028/kWh of 
electricity and $11.99 per 1000 cubic feet ($1.163/therm) of natural 
gas, based on EIA statistics for 2008 (the last complete year of data 
available in Table 5.3 Average Retail Price of Electricity to Ultimate 
Consumers: Total by End-Use Sector for the commercial sector--available 
from EIA at https://www.eia.doe.gov/cneaf/electricity/epm/table5_3.html 
and from the EIA Natural Gas Annual Summary for the commercial sector 
available at https://tonto.eia.doe.gov/dnav/ng/ng_pri_sum_dcu_nus_a.htm.) DOE recognizes that actual fuel costs will vary somewhat by 
building type within a region, and will in fact vary more across 
regions. Nevertheless, DOE believes that the use of simple national 
average figures illustrates whether there will be energy cost savings 
sufficient for the purposes of the DOE preliminary determination.
    Energy use intensities developed for each representative building 
type were weighted by total national square footage of each 
representative building type to provide an estimate of the difference 
between the national energy use in buildings constructed to both 
editions of the Standard 90.1. Note that the 15 buildings types used in 
the preliminary determination reflect approximately 80% of the total 
square footage of commercial construction including multi-family 
buildings greater than three stories covered under ASHRAE Standard 
90.1.
    Note that only differences between new building requirements were 
considered in this quantitative analysis. Changes to requirements in 
the 2007 edition that pertain to existing buildings only are addressed 
in the detailed textual analysis only.
    Both the 2007 and 2004 editions address additions and renovations 
to existing buildings. Since DOE has preliminarily found insufficient 
data to characterize renovations in terms of what energy using features 
are utilized, DOE has not determined that the results obtained from the 
whole building prototypes used would reasonably reflect the EUI 
benefits that would accrue to renovated floor space. For this reason, 
renovated floor space is not included in the DOE weighting factors. 
Building additions on the other hand are believed to be substantially 
equivalent to new construction. For this reason, FW Dodge construction 
data on additions has been incorporated into the overall weighting 
factors. Floor space additions reflect approximately 13 percent of new 
construction floor space based on data captured in the FW Dodge 
dataset.
    The quantitative analysis assumed the same base ventilation level 
for buildings constructed to Standard 90.1-2004 and Standard 90.1-2007. 
Neither edition of Standard 90.1 specifies ventilation rates for 
commercial building construction. ASHRAE has a separate ventilation 
standard for commercial construction, ASHRAE Standard 62.1 Ventilation 
for Acceptable Indoor Air Quality. This standard is cited only in a few 
exceptions within the mechanical sections of either ASHRAE 90.1-2004 or 
ASHRAE 90.1-2007, with each edition referencing a different version of 
standard 62.1. ASHRAE 90.1-2004 lists ASHRAE 62.1-1999 in its table of 
references. ASHRAE 90.1-2007 lists ASHRAE 62.1-2004 in its table of 
references. The latest version of ASHRAE Standard 62 is Standard 62.1-
2007.
    Ventilation rates can have significant impact on the energy use of 
commercial buildings. States and local jurisdictions typically specify 
the ventilation requirements for buildings within their respective 
building codes and can set these requirements independent of the energy 
code requirements. Because of the limited reference to ventilation 
within either the 2004 or the 2007 edition of ASHRAE 90.1, the 
requirements that States certify that their energy codes meet or exceed 
the 2007 edition of ASHRAE 90.1 would in general not require 
modification of State ventilation code requirements. However, in many 
cases, ventilation requirements can be traced back to requirements 
found in one or another version of ASHRAE Standard 62.1. For the 
purpose of the quantitative analysis, DOE assumed ventilation rate for 
the simulation prototypes based on the requirements ASHRAE 62.1-2004. 
DOE also performed a sensitivity analysis which calculated the 
quantitative impacts assuming a ventilation rate based on ASHRAE 
Standard 62.1-1999.
    The quantitative analysis of the energy consumption of buildings 
built to Standard 90.1-2007, as compared with buildings built to 
Standard 90.1-2004, indicates national primary energy savings of 
approximately 3.7 percent of commercial building energy consumption 
based on the weighting factors for the 15 buildings simulated. Site 
energy savings are estimated to be approximately 4.4 percent. Using 
national average fuel prices for electricity and natural gas DOE 
estimated a reduction in energy expenditures of 3.8 percent would 
result from the use of ASHRAE Standard 90.1-2007 as compared to ASHRAE 
Standard 90.1-2004. As identified previously, these estimated savings 
figures do not include energy savings from equipment or appliance 
standards that would be in place due to Federal requirements regardless 
of their presence in the ASHRAE Standard 90.1-2007.
    We also performed a detailed analysis of the differences between 
the textual requirements and stringencies of the two editions of 
Standard 90.1 in the scope of the standard, the building envelope 
requirements, the building lighting and power requirements, and the 
building mechanical equipment requirements.
    DOE works with the National Institute of Standards and Technology's 
(NIST) Building and Fire Research Laboratory on a variety of projects 
related to high-performance buildings. NIST is the main overseer of the 
Building Life Cycle Cost (BLCC) software used to support 10 CFR 436 and 
Federal life cycle costing requirements within the Federal sector. DOE 
and NIST co-chair the Building Technology Research and Development (BT 
R&D) committee under the Office of Science and Technology Policy (OSTP) 
as required under Section 913 of the Energy Policy Act of 2005. 
However, DOE does not typically work with NIST on determinations of 
energy efficiency of building standards. The technical work on DOE's 
determinations is provided by staff at Pacific Northwest National 
Laboratory's Building Energy Codes Program.
2. Detailed Textual Analysis
    The emphasis of our detailed requirement and stringency analysis 
was on looking at the specific changes that ASHRAE made in going from 
Standard 90.1-2004 to Standard 90.1-2007. ASHRAE publishes changes to 
their standards as addenda to the preceding standard and then bundles 
all the addenda together to form the next edition. ASHRAE processed 44 
addenda to Standard 90.1-2004 to create Standard 90.1-2007. Each of 
these

[[Page 54125]]

addenda was evaluated by DOE in preparing this preliminary 
determination.
    In addition, each standard has multiple ways to demonstrate 
compliance, including a prescriptive set of requirements by section of 
the standard, various tradeoff approaches within those same sections, 
and a whole building performance method (Energy Cost Budget; ``ECB''). 
For each addendum we identified whether it applies to the prescriptive 
requirements, or one of the tradeoff paths provided for in the 
envelope, lighting, or mechanical sections, or the ECB whole building 
performance path. For each addendum DOE identified the impact on the 
stringency for that path to compliance.

D. Preliminary Determination Statement

    DOE's review and evaluation indicates that there are significant 
differences between the 2004 edition and the 2007 edition. Our overall 
preliminary conclusion is that the 2007 edition will improve the energy 
efficiency of commercial buildings. However, DOE identified two changes 
in textual requirements that taken alone appear to represent a 
reduction in stringencies and could decrease energy efficiency. The two 
changes are addendum ``p'' broadens the implicit definition of 
``visually impaired'' as used in exceptions provided in the standard 
which allow for lighting power to not be included in the calculated 
lighting power densities subject to maximum limits and addendum ``av'' 
which provides for an explicit shading credit allowed for louvered 
projections, where such a credit was not explicitly provided for in 
90.1-2004. DOE believes that in these cases, the reduction in 
stringency was not considered a major impact. For the other addenda, 
DOE preliminarily determined that the remaining addenda either 
represented no change in stringency, or indicated a positive change in 
stringency corresponding to improved efficiency. Overall, DOE 
preliminarily concluded the changes in textual requirements and 
stringencies are ``positive,'' in the sense that they would improve 
energy efficiency in commercial construction. Our quantitative analysis 
preliminarily shows that for the 15 prototype buildings, a weighted 
average national improvement in new building efficiency of 3.7 percent, 
when considering source energy, and by 4.4 percent, when considering 
site energy. As both the 2004 and 2007 editions cover existing 
buildings, to the extent that these standards are applied to existing 
buildings in retrofits or in new construction addition, the 2007 
edition should improve the efficiency of the existing building stock. 
DOE has, therefore, preliminarily concluded that Standard 90.1-2007 
receive an affirmative determination under Section 304(b) of the ECPA.

II. Results of Quantitative Analysis

    Tables 3 and 4 show the aggregated energy use and associated energy 
savings by building type for the 15 building prototypes analyzed and on 
an aggregated national basis for the 2004 and 2007 editions, 
respectively. For each edition of Standard 90.1, the national building 
floor area weight used to calculate the national impact on building EUI 
or building ECI, is presented. The national average electricity and gas 
building energy use intensity is presented separately for each building 
prototype analyzed, electricity being the predominant energy usage in 
all prototypes. National-average site energy use intensities ranges 
from over five hundred Btu per square foot annually for the Fast Food 
prototype to approximately 28 Btu per square foot annually for the Non-
refrigerated Warehouse type. Source energy use intensities and building 
energy cost intensities ($/sf-yr) are also presented. Further details 
on the quantitative analysis can be found in the full preliminary 
quantitative analysis report available at https://www.energycodes.gov/implement/determinations_90.1-2007.stm.

                                         Table 3--Estimated Energy Use Intensity by Building Type--2004 Edition
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Building    Whole building EUI data for building population kBtu/ft\2\-yr
                                                                             type floor ----------------------------------------------------------------
               Building type                       Building prototype       area weight    Electric                                           ECI $/ft2-
                                                                                 %           EUI        Gas EUI      Site EUI    Source EUI       yr
--------------------------------------------------------------------------------------------------------------------------------------------------------
Office.....................................  Small Office.................         6.16         35.6          3.6         39.2        116.3        $1.11
                                             Medium Office................         6.64         42.1          4.2         46.3        137.5         1.32
                                             Large Office.................         3.65         34.4          5.7         40.1        114.6         1.10
Retail.....................................  Stand-Alone Retail...........        16.76         56.1         15.0         71.1        192.6         1.86
                                             Strip Mall...................         6.23         55.2         20.1         75.2        194.8         1.90
Education..................................  Primary School...............         5.49         47.9         23.5         70.5        175.3         1.72
                                             Secondary School.............        11.38         43.7         19.5         62.4        157.8         1