Inflation and higher borrowing costs pushed MISO’s cost of new entry up by about 5% heading into the 2026/27 planning year, but stakeholders are questioning the RTO’s use of 2020 data in calculations in order to keep prices lower.
This year, MISO’s cost of new entry (CONE) varies from $142,970/MW-year in Missouri’s Zone 5 to $123,250/MW-year in Mississippi’s Zone 10. On average, the 2026/27 CONE is almost $359/MW-day, higher than the roughly $341/MW-day used in the 2025/26 capacity auction and the $330/MW-day used during the 2024/25 planning year.
CONE is the annualized, capital cost of building a power plant. In MISO’s case, the RTO calculates values per local resource zone and uses them to establish price caps in its capacity market.
MISO used data from the U.S. Energy Information Administration’s (EIA) 2020 Capital Costs Report for its hypothetical, advanced combustion turbine example instead of relying on the agency’s new figures from the 2024 report.
The RTO said it wanted to stick with its usual, theoretical 240-MW simple cycle plant instead of the EIA’s new norm, which would more than double the size of the example plant. The RTO upped the cost of the 2020 plant to reflect inflation.
Joshua Schabla, senior market design economist at MISO, said the RTO didn’t meaningfully alter its CONE calculations this year but probablywould change them by the time it crunches numbers again in 2026.
MISO said it plans to change the reference technology used for its power plant example for the 2027/28 planning year. Schabla said MISO plans to begin discussing its new CONE resource reference beginning in November. (See Transition Spurs Power Producers to Ask for Fresh Look at MISO Cost of New Entry.)
Some stakeholders attending an Oct. 1 Resource Adequacy Subcommittee meeting said MISO should have used more up-to-date information to inform CONE. By not upping its reference prices to reflect the true state of the industry, MISO could risk its reliability, they said.
Representing the Coalition of Midwest Power Producers, Travis Stewart expressed concern that MISO’s reliance on 2020 data is “inconsistent with market signals that we’re hoping to create.”
“New gas turbines are two to three times more expensive than they were a year ago. That information should report back to the market. The objectivity of this is important,” Stewart said. He added that he worried that consumer advocates could draw on MISO CONE values to argue against cost recovery proposals for new generation in public service commission proceedings, since prices would not match.
Pelican Power’s Tia Elliott said MISO possibly was setting itself up for a “wide spread” between it and other grid operators.
However, Anna Sommer, principal at the Energy Futures Group, said she appreciated MISO being cautious before making “major” changes to CONE. She said because MISO’s capacity auction is a prompt-year auction and most member utilities are vertically integrated, the capacity auction should not be considered a source for long-term planning signals.
Schabla said MISO didn’t want to impose “supply shocks” on the market if they’re not going to last, adding that the RTO wanted to avoid publishing high prices only to have to downgrade them in ensuing years. He said there have been questions over the legality and the longevity of the tariffs imposed by the Trump administration. Had MISO incorporated all variables, CONE might have risen by a factor of two or three, Schabla said.
“It’s a little too early for us to make a decision like that and factor that into the price caps,” he said.
Werner Roth, economist with the Public Utility Commission of Texas, said had MISO produced numbers as much as three times higher than in 2024, governors of MISO states would have reacted poorly and made PJM’s continuing fallout over record-high capacity prices look like a “pillow fight.”
Schabla said he thought wildly volatile numbers year-over-year would be worse than not drawing on the freshest data available.
“Stability matters,” he said.