Global Solar Generation Exceeds Nuclear for First Time in 2025

Solar and Wind Surpass Nuclear Output

The World Nuclear Industry Status Report (WNISR) 2026 indicates that wind power first surpassed nuclear generation monthly in March 2025, followed by solar in April 2025. This marked the first instance of global monthly solar generation exceeding nuclear output. From March 2025 through June 2026, either solar or wind individually generated more electricity than nuclear each month.

Widening Gap in Capacity Growth

The report highlights a substantial widening of the gap between renewables and nuclear in 2025. Global solar capacity increased by 510 GW to 2,383 GW, a 27% year-on-year rise. Wind capacity grew by 159 GW to 1,291 GW, a 14% increase. In contrast, installed nuclear capacity rose by only 1.5 GW to 399.5 GW, while operating nuclear capacity decreased by 0.5 GW to 368.6 GW. Nuclear capacity has remained largely flat for over 25 years, while solar and wind have expanded rapidly.

Conservative Estimates and Market Reality

The WNISR's PV figures are based on conservative estimates; more recent data from IEA PVPS suggest global PV additions reached approximately 690 GW in 2025, 180 GW more than the report's figure. This implies an even wider gap between solar and nuclear capacity and their respective growth rates. Mycle Schneider, who oversees the WNISR, noted the challenging reality for the nuclear industry, citing instances like U.S. nuclear company Holtec postponing its IPO and Fermi's stock value decline.

Growth Rates and Future Outlook

While the world's operating nuclear fleet increased output by 1.1% (with output declining outside China), global solar power generation jumped by 30%, surpassing nuclear's annual electricity production for the first time. The report identifies falling battery costs as a factor enabling continued PV expansion, particularly as grids manage increasing volumes of variable renewable generation.