A review by the Sun Day Campaign of data from the Federal Energy Regulatory Commission (FERC) shows that solar and wind accounted for 100% of new electricity generating capacity added in the USA in March 2025, and 97.8% during the first quarter overall.
According to FERC’s Energy Infrastructure Update (covering data through 31 March 2025), 31 solar units with a combined capacity of 446MW were placed into service in March, along with one wind unit — the 223.9MW Shamrock Wind & Storage Project in Crockett County, Texas. These were the only new capacity additions during the month.
In total, solar and wind contributed 7,076MW of new capacity in the first quarter of 2025. Solar made up 72.3% of the quarterly additions, with wind contributing 25.5%. The remaining 2.2% was from natural gas (147MW) and oil (11MW).
Solar and wind now account for 10.7% and 11.8% respectively of total installed utility-scale generating capacity in the USA, representing a combined share of 22.5%. When including hydropower (7.7%), biomass (1.1%) and geothermal (0.3%), renewables collectively represent 31.5% of installed utility-scale capacity. If small-scale solar is also included, renewables now account for roughly one-third of total generating capacity in the country.
The share of utility-scale renewables has grown steadily from 29.4% in March 2024, 22.7% five years ago, and 16.9% a decade ago. Over that ten-year period, wind’s share has more than doubled, while solar has grown more than tenfold.
