Impact of solar energy on French electricity markets

Environmental constraints, including heatwaves and droughts, led to the shutdown of 13 nuclear reactors in France, representing roughly 20.4 percent of the nation’s total nuclear capacity. During this period, solar power played a critical role in stabilizing the grid, accounting for up to 35 percent of the French electricity mix.

This surge in solar energy contributed to extreme price volatility on the EPEX SPOT exchange, with wholesale prices frequently dropping to zero or entering negative territory during midday hours.

Subsequent analysis by the French Energy Regulatory Commission (CRE) examined the long-term economic impacts of renewable expansion. While the growth of solar and wind power between 2020 and 2025 helped lower market prices—providing an estimated €8 billion in benefits to consumers—the rapid increase in solar capacity has introduced new challenges. In 2025, France recorded 513 hours of negative prices and curtailed approximately 1.6 TWh of solar production. To maintain the economic value of solar assets, the CRE suggests that future projects must integrate flexibility measures such as energy storage and self-consumption.