Wire
Court keeps FERC’s backdated MISO refunds in play
The D.C. Circuit said FERC could use a 9.98% replacement return rate, with interest, to calculate refunds on disputed MISO transmission charges. The ruling keeps old bills and repayment exposure alive.
Electric customers tied to the Midcontinent Independent System Operator, or MISO, grid still face repayment risk on old transmission charges after the D.C. Circuit said the Federal Energy Regulatory Commission, or FERC, can reach back to correct its own mistakes even when earlier rate orders were vacated. The ruling keeps money already collected on those bills in play instead of treating it as settled.
The court’s bottom line is simple: a rate order going away does not always wipe out the agency’s power to order refunds for the same period. That leaves utilities, state regulators and customers with an open fight over charges that were already paid.
The rate reset
FERC set a just-and-reasonable replacement return at 9.98% and used that figure to calculate refunds on the disputed MISO transmission charges. It also added interest, which makes the repayment calculation larger than the bare rate difference.
The refund window reached from November 12, 2013, through February 11, 2015, and then again from September 28, 2016, to the date of the order. In practice, that means a defined stretch of old bills can still be recalculated rather than left untouched.
Why the backdating survived
The panel said vacating the earlier rate orders did not erase FERC’s remedial authority. It relied on City of Anaheim for the idea that the agency may order retroactive adjustments when it is fixing its own errors after being reversed in court.
That distinction matters because the refund remedy is treating the challenged billing period as unlawful, not offering FERC a free do-over. Once the court accepted that frame, the backdated refund path stayed open.
What remains on the bill
For transmission owners, the ruling means old charges on the MISO grid still carry repayment exposure. For customers, it keeps alive the possibility that some of what they already paid may come back.
The case does not erase the rate fight itself. It keeps the money question alive, and for everyone attached to that regional grid, that is the part that reaches the pocketbook.