ComEd Bills Jump 50% as PJM Capacity Crunch Spurs Illinois Storage Mandate
Illinois approved a virtual power plant program for ComEd as PJM's third consecutive capacity shortfall drives retail electricity costs sharply higher.
PJM Western Hub spot power stood at $78.03 per megawatt-hour as of Tuesday (2026-08-11), sustaining the elevated price environment that has already pushed ComEd's supply rates up roughly 50% over the past 18 months. Exelon CEO Calvin Butler attributed the rise primarily to a capacity shortage in PJM, the grid operator serving 67 million customers across 13 states.2,4
The grid's most recent base residual auction came up 6.8 gigawatts short of its procurement target, the third consecutive year PJM has failed to lock in sufficient forward capacity commitments, OilPrice.com reported on July 15 (2026-07-15). Capacity prices hit their price cap, leaving the market with no headroom to clear new supply at current auction parameters.6,7
Demand is making the deficit harder to close. PJM's instantaneous load touched 162.7 gigawatts on July 2 (2026), less than 3 gigawatts below the all-time demand peak set in 2006, according to figures cited in the Illinois Commerce Commission proceeding. Canary Media described PJM as "a poster child for how not to keep up with soaring energy demand," with data centers accelerating load faster than new generation can clear the interconnection queue and come online.5,4
Illinois moved quickly on the consumer side. Governor J.B. Pritzker signed the Clean and Reliable Grid Affordability Act in January 2026, shortly after a U.S. Congressional report found state retail electricity prices rose more than 15% in 2025. The law directs Illinois utilities to deploy 3 gigawatts of energy storage by 2030 and build virtual power plants using distributed assets including residential batteries, EV chargers and HVAC controls.5
The Illinois Commerce Commission approved ComEd's first program under that mandate in late June (week of 2026-06-29), greenlighting a battery-based scheduled dispatch virtual power plant. It replaced a narrower VPP that ComEd withdrew in November 2025, Utility Dive reported.5
But utilities alone are not moving fast enough for some market participants. Startup Base Power is enrolling ComEd-area homeowners in a residential battery program, selling retail electricity to participants at a 25% discount to the prevailing ComEd rate, which stood at 10.4 cents per kilowatt-hour this summer, according to Canary Media.4
Commercial-scale storage is expanding elsewhere in the PJM region too. Elevate Infrastructure and ArcLight Capital Partners began operating the 150-megawatt, 600-megawatt-hour Prospect Power battery project in Rockingham County, Virginia on June 11 (2026), with developers noting that accelerating electricity demand across Virginia and PJM had made battery storage an increasingly important grid component.3
PJM has also moved its backstop reliability auction to September, pulling it forward from a 2027 timetable. Waiting until 2027 was untenable given surging pressure from data center load growth, E&E News reported.1
Jefferies equity analysts said on Wednesday (2026-07-15) they expect long-term structural reforms to PJM's base residual auction, moving toward a continuing operating cost model with materially lower capacity prices. Without structural change, they warned, the grid risks heading toward what they called an "intervention doom loop," as repeated market failures invite escalating regulatory responses.7
The September backstop auction will be the next concrete signal for traders and utility planners. PJM needs new capacity commitments to begin closing the 6.8-gigawatt gap. A third shortfall in a row would keep prices at the ceiling and push Illinois's storage mandate from a policy target to an operational emergency — faster than the 2030 timeline envisions.1,5,6