On October 25, 2017, FERC conditionally accepted the Midcontinent Independent System Operator, Inc.’s (“MISO”) December 16, 2016 proposed revisions to the MISO Tariff, which were designed to improve the efficiency of MISO’s process for charging interconnection customers for “Quarterly Operating Limit” studies. FERC directed MISO to provide additional clarity in its proposed Tariff language and submit a compliance filing within thirty days.

Under Section 5.9 (Limited Operations) of the pro forma Generator Interconnection Agreement (“GIA”) contained in the MISO Tariff, interconnection customers may commence commercial operation of their interconnection projects prior to the completion of certain facilities required by their GIAs. The Quarterly Operating Limit studies determine the maximum output of a generating facility until the facilities required in the GIA are complete.

In its December 16, 2016 filing, MISO stated that while Section 5.9 of the GIA assigned responsibility for the costs of Quarterly Operating Limit studies to interconnection customers, the MISO Tariff did not provide a mechanism for MISO to efficiently collect a study deposit for those studies. Accordingly, MISO proposed a new Section 11.6 in Attachment X of its Tariff, which would require a $10,000 study deposit for interconnection customers that request Quarterly Operating Limit studies, and that it must be submitted 60 calendar days “prior to the start of the applicable binding quarter.” MISO estimated that the annual cost of these studies was approximately $2,500, but stated that asking for a larger deposit covering multiple years of studies would be administratively more efficient for MISO and interconnection customers, rather than asking for a deposit each year.

In its October 25, 2017 order, FERC conditionally accepted MISO’s proposed Tariff revisions, but agreed with commenters that the specific language submitted by MISO was unclear because it could be read to require a $10,000 study deposit in every quarter. Accordingly, FERC directed MISO to submit a compliance filing within thirty days revising the proposed language in Section 11.6 of Attachment X.

FERC’s order can be found here.