Mississippi Power Co. must study the early retirement of 950 MW of fossil-fueled generation in its next integrated resource plan, or IRP, as Mississippi regulators find the utility needs to reduce excess capacity.
“The evidence in this docket suggests that [Mississippi Power’s] current reserve margin is projected to be higher than targeted reserves and, if [Mississippi Power’s] units are left to operate through their remaining projected useful lives, this excess persists for over  years,” the Mississippi Public Service Commission wrote in a Dec. 17 order.
Regulators noted that Mississippi Power and a final report from Bates White Economic Consulting “both agree'” that the utility’s excess reserve capacity is “largely due to decreases in projected load primarily driven by changes in customer usage” since the company’s last IRP was filed in 2010.
“All agree that accelerating the retirement of some combination of [Jack Watson] units 4 and 5, [Greene County] units 1 and 2, and/or [Victor J. Daniel Jr.] units 1 and 2 represents the most attractive option for reducing [Mississippi Power’s] excess reserve margin,” regulators wrote.
The Southern Co. subsidiary is scheduled to file its next IRP in April 2021.
“[Mississippi Power’s] upcoming IRP filing should include the schedule of early or anticipated retirement of approximately 950 [MW] of generating capacity by year-end 2027 or show cause with detailed evidence why the continued operation of some or all of [Mississippi Power’s] existing fossil steam generation is in the best interest of customers and [Mississippi Power],” the order states. “To be clear, while there may be real and important operational constraints that could convince this commission to alter its findings in this order, the economic evidence available to the commission to date makes a compelling case for early retirement of some portion of [Mississippi Power’s] aging fossil steam generating fleet.”