Natural gas-fired combined-cycle (NGCC) power plants last year became the technology with the most electricity generating capacity in the United States, surpassing coal-fired plants, according to the Energy Information Administration (EIA).

In a Today in Energy post on Wednesday, EIA said generating capacity at NGCC plants totaled 264 GW in January, compared to 243 GW at coal-fired plants. NGCC plants accounted for about one-half of all domestic gas-fired generating capacity at the end of 2018 but provided almost 90% of total gas-fired generation, EIA said.

According to federal officials, about 40 GW of coal-fired capacity has been retired since the beginning of 2015, and no new coal capacity has come online in the United States since. During the same time, NGCC net capacity has grown by about 30 GW. Power generation from the NGCC capacity additions, as well as output from renewables, has largely offset the lost generation from coal retirements.

EIA said electricity generation from NGCC plants first surpassed coal-fired generation on a monthly basis in December 2015 and again in the first half of 2016. At those times, natural gas prices were relatively low. Higher natural gas prices reversed the trend until February 2018, when NGCC generation again surpassed coal generation.

"As more NGCC plants continue to come online and coal plants continue to retire, NGCC-powered electricity generation should consistently rank as the most prevalent source of electricity generation in the United States for the foreseeable future," EIA said, based on projections from its most recent Annual Energy Outlook.

Last month, PJM Interconnection’s independent market monitor reported that in 2018 gas-fired electricity output exceeded coal-fired generation for the first time in the history of the nation’s largest grid operator. Two months earlier, EIA projected that gas and renewables would account for most of the nation's power generation capacity additions in 2019, with most of the gas capacity additions, or 6.1 GW, from NGCC plants.