A new analysis from the Midcontinent Independent System Operator (MISO), the nation’s second-largest ISO, predicted that compliance with the Environmental Protection Agency’s (EPA’s) Clean Power Plan (CPP) could slash coal’s share of its generation from 59% in 2014 to potentially as low as 26% by 2030.
The report came ahead of MISO’s planning advisory committee meeting this week. MISO had previously estimated that 14 GW of its coal-fired capacity would close under the CPP.
The precise effect on coal generation in MISO depends on the path it takes to compliance, with varying scenarios depending whether coal is replaced by gas, greater renewables, or a mix of the two. A focus on expanding gas-fired capacity would cut coal generation by the greatest amount, from 381 TWh under a “business as usual” approach to 171 TWh—a 55% contraction. A focus on energy efficiency, with a build-out of renewable capacity, by contrast, would cut coal generation to 263 TWh, a 31% drop.
MISO officials have been saying for months that regional compliance is likely to be much less expensive than a state-by-state approach. The report notes that the latter approach would result in multiple islands of economic generation that would not be dispatched, while a regional approach would allow for much more efficient allocation of resources. Previous MISO analysis suggested the regional approach would save $3 billion in compliance costs.
Whether MISO will be able to convince the states in its service area to agree on a regional plan, however, remains to be seen, as the ISO serves several that sued to block the proposed rule earlier this year, though the D.C. Circuit threw out the case as premature earlier this month.
—Thomas W. Overton, JD is a POWER associate editor (@thomas_overton, @POWERmagazine).