FERC last week accepted MISO’s plan to allocate Michigan ratepayers $24.6 million in refunds for overcharges stemming from RTO-ordered system support resource agreements imposed on a Wisconsin Electric Power Co. coal-fired plant.

The commission directed MISO to execute the reallocation — which includes interest — over a 10-month period beginning Feb. 28 (ER14-2952-005).

FERC ruled in late October that WEPCo overcharged ratepayers on Michigan’s Upper Peninsula by almost $23 million for agreements that kept the 344-MW Presque Isle coal plant in Marquette, Mich., running in 2014 and early 2015 for reliability purposes. The commission directed MISO to calculate the refunds over the RTO’s objections that it did not provide clear guidance on how to do that. (See $23 Million Owed to Ratepayers in Presque Isle SSR Case.)

Now, Constellation Energy Group owes the largest share of SSR costs at $13.6 million, followed by Cloverland Electric Cooperative ($6.3 million), Upper Peninsula Power Co. ($4.9 million) and the city of Escanaba ($1.1 million). WPPI Energy is owed $3 million from Michigan LSEs. MISO redacted the monthly refund report in a public version of its filing because it would reveal “insight into monthly load patterns,” according to the RTO.

MISO had proposed to invoice the resettlements as a lump sum on Dec. 19, instead of over the original 14-month timeline. FERC determined that a 10-month distribution was more appropriate because it corresponded with the established April 3, 2014, refund effective date through the Jan. 31, 2015, termination of Presque Isle’s second SSR agreement.

— Amanda Durish Cook