Natural gas continued to gain in PJM Interconnection’s annual capacity auction held this month.

The auction cleared 1,000 MW more gas-fired generation than last year’s event, when 2,350 MW of gas-fired power cleared. Another new combined-cycle plant cleared in the latest auction, which procured power supplies for the period covering June 1, 2021 to May 31, 2022.

PJM is the nation’s largest grid operator, serving 65 million people in all or parts of 13 states and the District of Columbia, including shale-rich Ohio, Pennsylvania and West Virginia. Natural gas-fired generation has grown rapidly within the system in recent years, gains driven by abundant supplies and low commodity prices. Renewables have also continued to gain. Natural gas now accounts for more than 30% of PJM’s generation mix, compared to just a fraction more than a decade ago.

The annual auction is held to meet the region’s electricity needs three years ahead. Overall, PJM secured 163,627 MW for the 2021-2022 period. The auction produced a price of $140/ MW-day for much of the PJM footprint, compared with $76.53/MW-day in last year’s auction.

Prices were higher this year because of several factors, including continued low energy prices, which PJM said causes generators to seek revenues in the capacity market with higher offers. There was also a decrease in total cleared capacity, including a reduction of new generators. PJM secured 165,109 MW last year.

Higher prices, PJM said, were partially offset by a lower reliability requirement because of the expected decline in future electricity demand within the region.

Moody’s Investors Service Vice President Toby Shea said while new generators held back from entering PJM this year, higher-than expected prices are “credit positive” for all independent power producers operating in the grid’s footprint.

A total of 1,417 MW of wind cleared in the auction, up 529 MW from last year. Solar increased fourfold year/year, with around 570 MW clearing. The auction also cleared 500 MW more of coal-fired generation compared with 2017 and 19,900 MW of nuclear generation cleared as well, or about 7,400 MW less than in last year’s auction.