Solar eclipse on August 12 and heatwave “overwhelm” Europe’s power grid, experts warn: Risk of power outages

A rare solar eclipse on August 12 is expected to put additional pressure on Europe’s energy system, at a time when a heatwave and low water levels have forced some nuclear, coal-fired and hydroelectric power plants to reduce or halt production.

According to the European Commission, high temperatures have affected power generation in Hungary, Romania, Slovenia, France, Italy and Poland, as low river levels limit the water needed to cool power plants.

The situation is particularly difficult in Norway, where hydropower reservoirs have fallen to their lowest levels in around 30 years. Experts warn that Europe does not appear fully prepared for the combined pressure from high temperatures, drought and fluctuations in power generation.

The eclipse will further complicate the situation. The phenomenon will be total in northern Spain and northeastern Portugal, while more than 90% of the Sun will be obscured across large parts of Great Britain, France and northern Italy.

Spanish grid operator Red Eléctrica estimates that the eclipse could reduce the country’s solar power generation by up to 5 GW, equivalent to around 13% of peak energy demand on a typical August day.

At the European level, French grid operator RTE forecasts the loss of around 9.7 GW of power generation during the eclipse.

Electricity grid operators across the continent have been put on alert to compensate for the temporary decline in solar generation through other energy sources.

Great Britain is also expecting a reduction in solar generation of around 700 MW, while the most unfavorable scenarios forecast a decline of up to 1.3 GW.

Meanwhile, the heatwave has caused serious problems at several power plants. In Poland, two major coal-fired power plants have reduced or temporarily halted production because of the very low level of the Vistula River, losing around 1.3 GW of capacity.

In France, three nuclear reactors have been shut down because of low water levels, while in Romania, authorities intervened to divert the flow of the Danube toward the Cernavodă nuclear power plant, avoiding a complete shutdown.

Despite the tense situation, the European Commission says there are currently no immediate concerns about the security of electricity supplies, but acknowledges that the system is under pressure and that weather developments are being closely monitored.