Mich. Admin. Code R. 460.980

Current through Vol. 24-21, December 1, 2024

Section R. 460.980 - Capacity of the DER

Rule 80.

(1) If the interconnection application requests an increase in capacity for an existing DER, the electric utility shall evaluate the application based on the new export capacity of the DER. The maximum capacity of a DER is the aggregate nameplate rating. or may be limited as described in the electric utility's interconnection procedures.

(2) An interconnection application for a DER that includes single or multiple types of DERs at a site for which the applicant seeks a single point of common coupling must be evaluated as described in the electric utility's interconnection procedures.

(3) The electric utility's interconnection procedures may describe acceptable methods for power limited export DER including, but not limited to, reverse power protection and utilizing inverters or control systems so that the DER capacity considered by the electric utility for reviewing the interconnection application is only the amount capable of being exported. These methods for power limited export DER may be used as alternatives to the method described in subrule (4) of this rule.

(4) An electric utility shall allow interconnection of limited-export or non-exporting DERs according to this subrule. If a DER uses any configuration or operating mode in this subrule to limit the export of electrical power across the point of common coupling, then the capacity must be only the amount capable of being exported, not including any inadvertent export. To prevent impacts on system safety and reliability, any inadvertent export from a DER must comply with the limits in subdivisions (e) or (f) of this subrule. The export capacity specified by the applicant in the application must be included as a limitation in the interconnection agreement. Other means not listed in this subrule may be utilized to limit export if mutually agreed upon by the electric utility and applicant. Interconnections of limited-export or non-exporting DERs are subject to the following options:

To ensure power is never exported across the point of common coupling, a reverse power protective function may be provided. The default setting for this protective function must be 0.1% export of the service transformer's rating, with a maximum 2.0 second time delay.

To ensure at least a minimum amount of power is imported across the point of common coupling at all times and, therefore, that power is not exported, an under-power protective function may be provided. The default setting for this protective function is 5% import of the DER's total nameplate rating, with a maximum 2.0 second time delay.

The nameplate rating of the DER, minus any auxiliary load, must be so small in comparison to its host facility's minimum load that the use of additional protective functions are not required to ensure that power is not exported to the distribution system. This option requires the DER capacity must be no greater than 50% of the applicant's verifiable minimum host load over the past 12 months.

A reduced output rating utilizing the power rating configuration setting may be used to ensure the DER does not generate power beyond a certain value lower than the nameplate rating.

DERs may utilize a Nationally Recognized Testing Laboratory Certified Power Control System and inverter system that results in the DER disconnecting from the distribution system, ceasing to energize the distribution system, or halting energy production within 2 seconds if the period of continuous inadvertent export exceeds 30 seconds. Failure of the control or inverter system for more than 30 seconds, resulting from loss of control or measurement signal, or loss of control power, must result in the DER entering an operational mode where no energy is exported across the point of common coupling to the distribution system.

DERs may be designed with other control systems or protective functions, or both, to limit export and inadvertent export to levels mutually agreed on by the applicant and the electric utility. The limits may be based on technical limitations of the applicant's equipment or the distribution system's equipment. To ensure inadvertent export remains within mutually agreed-upon limits, the applicant shall use an internal transfer relay, energy management system, or other customer facility hardware or software.

Mich. Admin. Code R. 460.980

2023 MR 8, Eff. 4/25/2023