MISO’s 2026/2027 Auction Came in Below Last Year’s Summer Peak

MISO conducts a Planning Resource Auction, or PRA, each planning year to establish seasonal capacity pricing. Those auction results are one of the inputs used to calculate capacity costs for businesses across the MISO footprint.

For perspective, the prior year’s summer auction result reached $666.50/MW-day. In the newly announced 2026/2027 planning year results, MISO reported lower summer clearing prices, including $424.30/MW-day for North/Central, $384.10/MW-day for LRZs 8 and 10, and $412.10/MW-day for LRZ 9.

Why the Auction Cleared Lower

According to MISO’s 04/28/2026 PRA results posting, the lower outcome was largely driven by increased supply.

MISO stated that:

• more capacity was offered than last year
• capacity offered into the auction increased by as much as 4%
• new capacity and more imports outweighed lower accreditation and retirements or suspensions

MISO also reported that the summer surplus above target increased from 2.6 GW in 2025 to 4.6 GW in 2026, even with a higher planning reserve requirement. In practical terms, more supply showed up this year, and that helped bring auction results down from the prior year’s extreme summer level.

Key Auction Results

MISO reported annualized capacity pricing for the 2026/2027 planning year in the range of $116 to $126 per MW-day, depending on zone grouping.

Seasonal clearing prices were reported as:

• Summer
  • $424.30/MW-day for North/Central
  • $384.10/MW-day for LRZs 8 and 10
  • $412.10/MW-day for LRZ 9
• Fall: $33.92/MW-day
• Winter: $35.97/MW-day
• Spring: $7.61/MW-day

MISO also said the auction cleared above seasonal initial reliability targets. For summer, the reserve margin cleared at 11.40% versus a 7.90% target, reflecting a stronger position than many had expected heading into the auction.

Many Large Customers Are Acting Earlier

One of the more important signals in MISO’s report is how many large customers are already taking a proactive approach to capacity management.

MISO stated that most customers, approximately 92%, secured capacity ahead of time or self supplied, reducing their sensitivity to the final auction outcome. That reflects a broader shift toward earlier procurement decisions and more active management of capacity exposure.

Why Capacity Strategy Still Matters

Even with a lower auction result, MISO made clear that summer remains tight. The report notes that additional capacity will still be needed over time, particularly as large-load growth continues.

For large business customers, that means one lower auction should not be viewed as a signal that future capacity costs will remain low or stable. Capacity strategy still matters, particularly in a market where pricing can change significantly from one planning year to the next.

Procurement Strategy & Capacity Costs

Your capacity cost is calculated by season using:

• the PRA price in $/MW-day
• your seasonal PLC
• the number of days in each season

Capacity costs are often managed in one of two ways within a customer’s energy structure:

• Converted into a $/MWh cost for inclusion in a fixed price, or
• Passed through via a monthly demand charge

In practice, the right fit depends on a customer’s budgeting goals, operating profile, and appetite for market exposure. Customers that value predictability may prefer a more fixed approach, while others may want to retain more flexibility depending on how they view future market conditions.

What Large Businesses Should Consider

1. How much capacity exposure they want to retain.
2. Whether their current structure aligns with budget certainty or market flexibility goals.
3. How future changes in supply, demand, and auction outcomes could affect total delivered cost.
4. Sign up for 1 Coincident Peak (CP) Service to receive notifications when demand peaks on the MISO system.

Bottom Line

The 2026/2027 MISO PRA cleared lower than the prior year’s elevated summer result because more capacity was offered into the market and reserve margins improved. At the same time, MISO continues to describe summer conditions as tight, which means capacity should remain an active consideration in procurement strategy for large business customers.

SOURCE MISO 2026 PRA Results Posting 20260428.pdf