Solar power supplied more electricity than coal in the United States for the first time in May, marking a significant milestone in the country's energy transition. According to data released by global energy think tank Ember, solar generated 12.8% of the nation's electricity during the month, while coal provided 12.2%.

The achievement represents coal's fourth-lowest monthly share on record, highlighting the continued decline of the fossil fuel in America's energy mix. Solar power has maintained its position as the leading source of new electricity capacity additions in recent years.

The milestone occurred despite federal policies that have favored traditional energy sources. Solar's growth has been driven by declining costs, improved technology, and state-level renewable energy policies across various regions of the country.

Data supporting the findings came from the Solar Energy Industries Association and analytics firm Wood Mackenzie, which have been tracking the sector's expansion. The organizations noted that solar installations continue to grow at a steady pace nationwide.

The shift reflects broader changes in the US electricity sector, where natural gas has become the dominant fuel source while renewable energy sources like solar and wind have gained substantial market share over the past decade. Coal, which once dominated American electricity generation, has seen its role diminish as utilities retire older plants and invest in cleaner alternatives.