On December 30, 2021, FERC accepted the Midcontinent Independent System Operator, Inc.’s (“MISO”) revisions to its Generator Interconnection Procedures (“GIP”), which MISO proposed to, among other things: (1) classify fuel type change requests made during the three-phase Definitive Planning Phase (“DPP”) of MISO’s generator interconnection study process as a material modification, and (2) allow interconnection customers to request surplus interconnection service earlier in the interconnection study process. As FERC found, MISO’s proposed changes represented a “reasonable compromise” to allow interconnection customers to request an earlier review of fuel change request through the surplus process, while minimizing disruptions to the formal DPP process posed by fuel type changes.

As explained in the Order, MISO’s proposed GIP revisions were primarily designed to correct an unintended outcome of MISO’s Order Nos. 845 and 845-A compliance filings. Specifically, as determined by FERC in a later proceeding, MISO’s GIP language adopted through its Order No. 845 compliance filings permitted fuel type changes to be a form of permissible technological advancement, thereby allowing interconnection customers to change the fuel source of their generating facilities well after the commencement of the DPP. As MISO explained, allowing fuel changes midway through the interconnection process may allow customers to “game” the Tariff’s site control requirements and may cause study and queue administration incongruities resulting in delays or uncertainties.

MISO filed proposed revisions on November 1, 2021, to prohibit fuel type modifications in the interconnection process, but also to allow more flexibility in the surplus interconnection process for interconnection customers seeking to integrate additional fuel sources. Specifically, MISO proposed the addition of a new section 4.4.5 to its GIP, which classifies fuel change requests made after entering the DPP as material modifications, except for hybrid resources that drop one fuel type before the start of DPP Phase I. Also, MISO proposed to revise GIP section to allow interconnection customers to request, and MISO to begin processing, interconnection requests for surplus interconnection service after the completion of Decision Point II for a generating facility with a valid interconnection request from which such service will be obtained upon request, instead of the current timing, which is after an interconnection customer obtains an effective interconnection agreement for a generating facility. Finally, MISO proposed revisions to GIP sections 7.2 and 3.3.1 to clarify ambiguity in the Tariff as to when an interconnection request enters the DPP and when interconnection studies begin.

FERC accepted MISO’s proposed GIP revisions. Specifically, FERC acknowledged that Order No. 845 did not require Transmission Providers to allow fuel changes as a form of permissible technological advancement. In addition, FERC found it was a “reasonable compromise” for MISO to restrict fuel changes in the formal DPP process while allowing interconnection customers to nonetheless seek to interconnect different resources through earlier processing of surplus requests.

The Order Accepting the GIP Revisions is available here.