Spain's Grid Hits Record 42 GW of Solar as Iberian Heatwave Pushes Temperatures Past 44°C

Spain's electricity grid hit a record 42 gigawatts of solar generation at 14:15 local time on Tuesday, enough to meet 73% of total demand during the peak hour, according to data published by Red Eléctrica de España. The milestone came on the same day that AEMET, Spain's national meteorological agency, confirmed the country is on track for its hottest July on record.

How It Happened

The combination of clear skies, an aggressive build-out of utility-scale solar in Castilla-La Mancha and Extremadura, and an unusually long day length in late July produced a generation profile that was almost flat between 13:00 and 16:00. The grid operator exported surplus to Portugal and Morocco during the peak, and prices in the day-ahead market briefly went negative for the second time this summer.

「This is no longer a curiosity. It is a recurring feature of the Iberian grid,」 said Jorge Morales, head of energy markets at consultancy AleaSoft. 「We will see negative prices more often than not during the May-July window.」

The Heatwave

AEMET said 41 of its 138 main weather stations exceeded 40°C on Tuesday, with Córdoba hitting 44.6°C — the highest reading of the year so far. The heatwave, which started on Saturday, is expected to extend into southern France and northern Italy through Sunday before a cold front pushes temperatures back toward seasonal norms. Public-health authorities in Madrid have issued an orange alert for the over-65 population through Friday.

Why It Matters

The simultaneous record solar and the record heat illustrate the central tension of the European energy transition. A grid that runs on solar can absorb a heatwave on the supply side, but a continent that runs on electrified cooling will see demand spikes that strain the system on the demand side. Spain's interconnections to France, currently limited to 2.8 GW, are the next bottleneck.