Understanding the Pre-Auction Numbers
- 175.6 GW installed capacity: The total nameplate generation within the MISO footprint. This includes all fuel types — gas, coal, wind, solar, nuclear, hydro.
- 135.6 GW accredited capacity: The effective capacity after MISO applies accreditation derates based on historical performance, availability, and capacity value. Wind and solar are heavily derated; thermal units lose credit for forced outage rates.
- 137.5 GW PRM requirement: The capacity needed to cover the 124.7 GW coincident peak plus a planning reserve margin, typically 10-11%.
- 1.9 GW gap: The preliminary shortfall between accredited capacity and the PRM target. Resource registrations are still in progress, which could narrow the gap before the March 26 offer deadline.
What Changed Since Last Year
- Load growth: The coincident peak forecast rose ~2 GW year-over-year, driven by data center load growth in MISO North/Central and industrial electrification across the Midwest.
- Coal retirements: Despite emergency extensions keeping some coal plants online, net coal capacity continues to decline. MISO relies on ~24 GW of expedited generation from 3 ERAS fast-track cycles to backfill.
- Demand response tightening: MISO’s new mandate for real performance verification (not mock drills) has reduced paper DR capacity, lowering the accredited total.
Offer Window: March 26–31
The PRA offer window opens on March 26 and closes on the last business day of March. Key dynamics to watch:
- Zone separation: MISO North/Central has been structurally tighter than South. If the 1.9 GW gap concentrates in the North/Central zones, those regions could see clearing prices at or near the Cost of New Entry (CONE) cap.
- Last year’s precedent: The 2025/26 PRA saw capacity prices 10× higher year-over-year, with summer clearing at $666.50/MW-day across all zones. A similar outcome is possible if the gap doesn’t close.
What This Means for Commercial Buyers
- Midwest capacity charges rising: If the PRA clears above $500/MW-day, Midwest commercial electricity bills will see meaningful capacity component increases starting June 1, 2026.
- Fixed-price contract timing: Buyers with contracts expiring before June 2026 should lock in renewal rates before PRA results (April 28) are published. Post-results, suppliers will reprice to reflect clearing.
- Demand response enrollment: MISO’s elevated capacity prices make demand response enrollment highly valuable. C&I facilities in MISO territory should explore curtailable load programs before the June 1 delivery year begins.
- Watch the gap: If late resource registrations close the 1.9 GW gap, clearing prices may moderate. Monitor MISO data updates through March 19.
Source: MISO Preliminary PRA Data (March 2026); RTO Insider; MISO ERAS Cycle III Report; MISO 2026/27 Demand Response Accreditation Guidelines.