Solar eclipse: in Europe, electricity grid managers have anticipated the drop in photovoltaic production

On Wednesday evening, an eclipse is expected to disrupt solar energy production across parts of Europe, casting shadows on the region's increasingly solar-powered power grids. Although the celestial phenomenon is rare and has been predicted centuries ahead, its impact on solar generation will be relatively minimal due to the sun being near the horizon at the time of the eclipse. Alternative energy sources, such as natural gas, hydropower, and nuclear plants, will step in to meet the increased demand.

The UK's grid operator has issued a warning about tight margins for Wednesday evening, advising market participants to provide spare generation to cope with the shortfall. In response, Britain's National Energy System Operator has forecasted a 1.8 gigawatt margin shortfall starting at 5pm local time. This precautionary measure is not unprecedented, as similar warnings have become more common this summer due to extreme heat in Europe, which has curtailed output from conventional sources such as nuclear and hydropower.

While the eclipse will have a limited effect on the UK, with generation expected to drop by more than one gigawatt, the impact will vary across Europe. The extent of the reduction will depend on the time of the eclipse, its coverage, and the size of each country's solar capacity. Overall, solar output in Europe could decrease by approximately 9.7 gigawatts during the eclipse, starting around 7.15pm.

Spain, where the eclipse will be total, is well-prepared for the event. Solar farm operators, such as Acciona, are coordinating closely with the nation's power system operator, Red Electrica, and are incorporating the eclipse into their generation forecasts. Despite the eclipse occurring at sunset when solar output is already declining, Acciona believes that flexible resources like hydroelectric plants and combined-cycle gas turbines will be sufficient to compensate for any temporary loss of solar power.