U.S. solar power generation exceeded coal generation on a monthly basis for the first time, Cleantechnica reported on Thursday, citing data from energy analytics firm Ember.

Ember said U.S. solar power generation in May 2026 rose to a record 45.5 TWh. That was up 17 percent from the same month a year earlier. Solar is now the United States' third-largest power source after natural gas and nuclear. Over the past five years, solar's share in the U.S. power mix more than doubled to 12.8 percent from 5.4 percent. Over the same period, coal's share fell by about half to 12.2 percent from 19.7 percent. Coal generation was down 11 percent from a year earlier.

Nicholas Fulghum (니콜라스 풀검), a senior data analyst at Ember, said, "The fact that solar has overtaken coal for the first time shows it has moved from a niche energy source to the third and fastest-growing power source in the U.S. power system."

Private capital is also flowing quickly. Solar and energy storage company Origis Energy recently raised $900 million in new financing. The cumulative amount raised over the past three months exceeded $1.4 billion. Solar investment is accelerating even as the Trump administration pressures the renewable energy industry by clawing back federal offshore wind leases. Origis has more than 20 GW of solar and storage projects in its pipeline, and quadrupled its operating scale in the 24 months since Trump's inauguration.

Global financial institutions including First Citizens Bank, ING Capital, Natixis and Santander participated in the financing. Origis had previously raised an additional $545 million in March for a 700 MW solar pipeline in Texas.

Solar may again fall behind coal in the second half due to seasonal factors. But Ember said summer solar generation is likely to set another record.