Code of Colorado Regulations
700 - Department of Regulatory Agencies
723 - Public Utilities Commission
4 CCR 723-3 - RULES REGULATING ELECTRIC UTILITIES
INTERCONNECTION PROCEDURES AND STANDARDS
Section 3855 - Level 2 Process (Fast Track)

(I) Eligibility for the Level 2 Process is determined based upon the type and size of the interconnection resource as well as the voltage of the utility line and the location of and the type of utility line at the point of interconnection. An interconnection customer may determine whether the interconnection resource is eligible for the Level 2 Process by requesting a pre-application report pursuant to subparagraph 3853(a)(IV).

(II) For certified inverter-based systems, the size limit of the interconnection resource varies according to the voltage of the utility line at the proposed point of interconnection. Certified inverter-based interconnection resource facilities located within 2.5 electrical circuit miles of a substation and on a mainline are eligible for the Level 2 Process under the higher thresholds pursuant to this rule 3855. The utilities should define "mainline" in their interconnection tariff.

(III) All synchronous and induction facilities must be no larger than 2 MW AC to be eligible for the Level 2 Process, regardless of location.

(IV) In addition to the size threshold, the interconnection resource must meet the codes, standards, and certification requirements specified in certain of these interconnection rules.

(V) A utility may utilize tools that perform screening functions using different methodology from that set out in paragraph 3855(d) as long as the analysis is aimed at preventing the same voltage, thermal and protection limitations specified under rule 3855 and otherwise complies with these rules.

(I) The proposed interconnection resource's point of interconnection must be on a portion of the utility's distribution system that is subject to the utility's tariffs. Proposed interconnection resources on highly seasonal circuits shall also be subject to the supplemental review pursuant to paragraph 3855(d).

(II) For interconnection of a proposed interconnection resources to a radial distribution circuit, the aggregated generation, including the proposed interconnection resources, on the line section(s) shall not exceed 15 percent of the line section's annual peak load as most recently measured at the substation or calculated for the line section(s). A line section is that portion of a utility's electric system connected to a customer bounded by automatic sectionalizing devices or the end of the distribution line. A fuse is not an automatic sectionalizing device. Energy storage system(s) capacity for purposes of this screen shall be based on subparagraph 3853(c)(III).

(III) The proposed interconnection resource, in aggregation with other generation on the distribution circuit, shall not contribute more than ten percent to the distribution circuit's maximum fault current at the point on the distribution feeder voltage (primary) level nearest the proposed point of change of ownership.

(IV) The proposed interconnection resource, in aggregate with other interconnection resource on the distribution circuit, shall not cause any distribution protective devices and equipment (including, but not limited to, substation breakers, fuse cutouts, and line reclosers), or interconnection customer equipment on the system to exceed 87.5 percent of the short circuit interrupting capability; nor shall the interconnection be proposed for a circuit that already exceeds 87.5 percent of the short circuit interrupting capability.

(V) The proposed interconnection resource shall meet the rapid voltage change and flicker requirements of IEEE Standard 1453 (2015) and IEEE Standard 1547-2018, until January 1, 2022, or until such time new DERs applying for interconnection will comply with IEEE 1547- 2018 based on the appropriate test. This rule does not include any later amendments or editions of these standards. These standards are available for public inspection at the Commission's office, 1560 Broadway, Suite 250, Denver, CO 80202.

(VI) The type of interconnection to a primary distribution line shall be determined based on the table below, including a review of the type of electrical service provided to the interconnection customer, line configuration, and the transformer connection to limit the potential for creating over-voltages on the utility's electric power system due to a loss of ground during the operating time of any anti-islanding function.

(VII) If the proposed interconnection resource is to be interconnected on single-phase shared secondary, the aggregate generation capacity on the shared secondary, including the proposed small generating facility, shall not exceed 25 kW. Energy storage system(s) capacity for purposes of this screen, shall be based on subparagraph 3853(c)(III).

(VIII) If the proposed interconnection resource is single-phase and is to be interconnected on a center tap neutral of a 240 volt service, its addition shall not create an imbalance between the two sides of the 240 volt service of more than 20 percent of the nameplate rating of the service transformer.

(IX) No construction of facilities by the utility on its own system shall be required to accommodate the small generating facility.

(X) For interconnection of a proposed interconnection resource to the load side of spot network protectors serving more than a single customer, the proposed interconnection resource must utilize an inverter-based equipment package and, together with the aggregated other inverter-based interconnection resource, shall not exceed the smaller of five percent of a spot network's maximum load or 300 kW. For spot networks serving a single customer, the interconnection resource must use inverter-based equipment package and either meet the requirements above or shall use a protection scheme or operate the generator so as not to exceed on-site load or otherwise prevent nuisance operation of the spot network protectors.

(XI) For interconnection of a proposed interconnection resource to the load side of area network protectors, the proposed interconnection resource must utilize an inverter-based equipment package and, together with the aggregated other inverter-based interconnection resource, shall not exceed the smaller of ten percent of an area network's minimum load or 500 kW AC.

(XII) The nameplate capacity of a proposed interconnection resource, in combination with the nameplate capacity of any previously interconnected interconnection resource, shall not exceed the capacity of the customer's existing electrical service unless there is a simultaneous request for an upgrade to the customer's electrical service, regardless of exporting or non-exporting designations for any of the interconnection resources.

(I) If the proposed interconnection fails the screens, but the utility does not or cannot determine from the initial review whether the interconnection resource may nevertheless be interconnected consistent with safety, reliability, and power quality standards unless the IC is willing to consider minor modifications or further study, the utility shall provide the IC with the opportunity to attend a customer options meeting. The utility shall provide to the IC in writing with a detailed information on the reasons(s) for failure.

(II) If the utility determines the interconnection request cannot be approved without minor modifications at minimal cost; without a supplemental study or other additional studies or actions; or without significant costs to address safety, reliability, or power quality problems, the utility shall notify the IC within the five business day period after the determination and provide the data and analyses underlying its conclusion. Within ten business days of the utility's determination, the utility shall offer to convene a customer options meeting with the utility to review possible IC facility modifications or the screen analysis and related results, to determine what further steps are needed to permit the small generating facility to be connected safely and reliably. At the time of notification of the utility's determination, or at the customer options meeting, the utility shall:

(I) To accept a utility's offer to conduct a supplemental review, the interconnection customer, within 15 business days of the offer, shall agree in writing to the supplemental review and submit a deposit for the estimated costs. If the written agreement and deposit have not been received by the utility within the 15 days, the interconnection request shall continue to be evaluated under the Level 3 Process, unless the request is withdrawn by the IC. The IC shall be responsible for the utility's actual costs for conducting the supplemental review. The IC must pay any review costs that exceed the deposit within 20 business days of receipt of the invoice or resolution of any dispute. If the deposit exceeds the invoiced costs, the utility will return such excess within 20 business days of the invoice without interest.

(II) Within 30 business days following receipt of the deposit for a supplemental review, the utility will perform a supplemental review of the proposed interconnection resource using the screens set forth below, notify the interconnection customer of the results of the screens in writing, and include with the notification copies of the analysis and data underlying the utility's determinations.

(III) The interconnection customer may specify the order in which the utility completes the supplemental review screens.

(IV) The utility shall notify the interconnection customer of the failure of the interconnection resource in any supplement review screen or of the utility's inability to perform any screen for the interconnection resource. Within two business days of the receipt of such notice, the interconnection customer may grant the utility permission:

(V) Minimum load, minimum loading, and minimum load data shall be specific to time(s) that the interconnection resource exports active power to the utility.

(VI) Supplemental review screens.

(VII) If the supplemental screening meets utility determined adequacy with minor modifications, the utility shall provide a non-binding good faith estimate of the limited cost to make such modifications to the utility's electric system upon notification of review results.

(I) If the proposed interconnection passes the screens, the interconnection request shall be approved and the utility will provide the IC an executable interconnection agreement within five business days after the determination.

(II) If the proposed interconnection fails the screens, but the utility determines that the small generating facility may nevertheless be interconnected consistent with safety, reliability, and power quality standards, the utility shall provide the IC an executable interconnection agreement within five business days after the determination.

(III) If the interconnection customer agrees to pay for the modifications to the utility's electric system as identified by the utility pursuant to subparagraph 3855(c)(II)(A), the utility will provide the interconnection customer with an executable interconnection agreement within ten business days of the customer options meeting.

(IV) If the interconnection customer agrees to pay for the modifications to the utility's electric system as identified by the utility pursuant to subparagraph 3855(d)(VII), the utility will provide the interconnection customer with an executable interconnection agreement within five business days of IC agreement to pay.