Spain's extreme heat forces nuclear cuts, health alerts in Galicia and solar investor pull‑out

A prolonged heat wave across Spain has led to multiple impacts. Nuclear operators report that several reactors have reduced output or temporarily halted production to avoid exceeding river‑water temperature limits, a precaution aimed at protecting aquatic ecosystems rather than reactor safety. The seven operating plants, including Almaraz, Ascó, Cofrentes, Trillo and Vandellós II, rely on river, reservoir or sea water for cooling, and high ambient temperatures have triggered these reductions.

In Galicia, the regional government has imposed a red heat alert for the interior of Pontevedra and an orange alert for the coastal Rías Baixas. Temperatures are expected to reach 40‑41 °C, prompting the suspension of federated outdoor sports between midday and evening and urging the public, especially the elderly, children and those with chronic illnesses, to stay hydrated and avoid the hottest hours.

Separately, investors are retreating from Spain’s solar sector as midday over‑production has driven electricity prices negative, undermining the profitability of photovoltaic parks. The situation follows the large‑scale blackout of April 2025, which highlighted the fragility of a grid dominated by intermittent renewables. Spain’s government, led by Prime Minister Pedro Sánchez, plans to invest €30 billion in grid modernization and storage by 2030 to stabilize the system and support the renewable transition.