Solar Power Surpasses Global Nuclear Generation for the First Time
Renewable energy capacity growth significantly outpaces stagnant nuclear power production worldwide.
1Historic Shift in Generation
For the first time, global monthly solar generation exceeded nuclear output in April 2025. Between March 2025 and June 2026, solar or wind individually generated more electricity than nuclear power every month. This milestone marks a significant transition in the global energy mix as renewable technologies scale rapidly while nuclear output remains largely stagnant.
2Capacity Growth Disparity
Global solar capacity surged by 510 GW to reach 2,383 GW in 2025, representing a 27% year-on-year increase. Conversely, installed nuclear capacity rose by only 1.5 GW to 399.5 GW, with operating capacity actually declining by 0.5 GW. Nuclear capacity has remained essentially flat for over 25 years despite recent construction efforts.
3Nuclear Industry Financial Struggles
Nuclear companies face mounting investor skepticism due to poor on-ground progress. U.S. firm Holtec recently halted a planned $1 billion IPO, while peer company Fermi saw its stock value plummet by 80% since October 2025. Investors are increasingly prioritizing the high growth rates of solar power over the slow-moving, capital-intensive nuclear sector.
4Regional Concentration of Nuclear
Nuclear expansion is currently concentrated in China and Russia, which dominate new reactor construction. While China saw a 7.6% increase in nuclear generation in 2025, production outside the country declined by 0.2%. Globally, nuclear's share of electricity generation dropped to 8.8%, roughly half of its 17.5% peak recorded back in 1996.
5Construction Delays and Challenges
New nuclear projects consistently face long timelines and significant delays. None of the 16 reactors connected to the grid between 2023 and 2025 met their original schedules, averaging 10.9 years for construction. Some projects, such as Slovakia’s Mochovce-4 and Iran’s Bushehr-2, have faced multi-decade timelines, highlighting the persistent difficulty of delivering nuclear infrastructure.
6The SMR Commercial Uncertainty
Small modular reactors (SMRs) are frequently promoted as a solution for market expansion, yet commercial success remains elusive. Despite significant government funding, no SMR claims regarding lower costs or modular efficiency have materialized at scale. Many designs exceed the 300 MW threshold, and some may generate significantly more nuclear waste than larger reactors.
7Battery Storage as Enabler
Falling battery costs are accelerating solar integration into grids facing variable renewable generation. Grid-scale battery deployment reached 104 GW and 257 GWh in 2025 alone. Over 78% of cumulative battery energy storage system capacity was installed between 2023 and 2025, providing a necessary mechanism to manage periods of low or negative electricity prices.
8Future Energy Market Outlook
The widening gap between renewables and nuclear underscores a fundamental shift in energy economics. With nuclear generation declining outside of China and solar growth rates hitting record highs, the market is favoring modular, faster-deploying technologies. Future energy security will likely depend on how effectively grids can integrate variable renewables with advanced storage solutions.
Original article: Hacker News — Solar Power Surpasses Global Nuclear Generation for the First Time