The solar eclipse of August 12 could cause a drop of 9.700 MW in European photovoltaic production

The solar eclipse of August 12, 2026, is expected to cause a rapid variation in photovoltaic production in Europe. The phenomenon will be total in some regions of Spain and partial in France, where the Sun could be obscured by up to 99% in some areas, according to RTE.

"In a matter of tens of minutes, the decrease and then the return of sunlight will lead to rapid variations in photovoltaic production." RTE emphasizes this in a press release.

A decrease of 9.700 MW is expected across Europe.

According to estimates from the French network manager, European solar production could fall by nearly 9.700 MW at the height of the eclipse, equivalent to 3,7% of the photovoltaic capacity installed in the European Union.

In France, the amount of solar power fed into the grid could decrease by approximately 1.800 MW if the sky is clear. This decrease would represent roughly 3% of the national electricity production expected at that time.

"Across Europe as a whole, France is much less impacted than Germany (3.300 MW) or Spain (3.000 MW)." RTE told AFP.

The event, whose effects on electricity production are expected between 19:30 p.m. and 21:30 p.m., will also be monitored at the European level by ENTSO-E, the association that coordinates electricity transmission system operators.

A management challenge for network managers

The drop in sunlight, followed by its return within a few dozen minutes, will require managers to quickly adapt the operation of the electrical system. Their mission is to constantly maintain the balance between electricity produced and consumed in order to guarantee security of supply.

RTE, however, does not anticipate any impact on the supply to French consumers. Electricity production should be sufficiently abundant, and the eclipse will occur at the end of the day, once the main peaks in photovoltaic production have passed.

The rapid development of solar energy, however, underscores the importance of this preparation. At the time of the 1999 eclipse, photovoltaics were still in their infancy, with approximately 1 GW of installed capacity worldwide. France now has over 30 GW of photovoltaic capacity.

The precedent of the 2015 eclipse

Network operators have already faced this type of phenomenon. During the partial eclipse of March 20, 2015, photovoltaic production decreased by approximately 2.000 MW in France, while the drop reached 35 GW across Europe.

"Thanks to meticulous preparation and coordination among network managers at the European level, the system was operated smoothly in real time." RTE reminds us.