Plans are in the works to protect Europe’s power supply during a total solar eclipse due on Friday, 20 March.

The eclipse is predicted to occur between 08:40 and 12:50 CET, during which time around 35 GW of solar power is expected to gradually fade from grids across Europe, and then gradually return. Countries such as Germany, where solar power contributes around one quarter of the total energy supply, will be most affected, with a knock-on effect for the neighbouring nations connected to its grid

A report from the European Network Transmission System Operators for Electricity (ENTSO-E), released this week, rated Germany (with 39,764 MW of solar power installed), Italy (19,691 MW), Spain (6739 MW), France (5419 MW) and Belgium (3245 MW) as the nations with the highest level of solar penetration, and thus those at greatest risk of power disruption. For example, the predicted reduction in Germany’s power supply is 16,916 MW, or 51 per cent of the nation’s solar energy supply.

While ENTSO-E said this week that it has been planning “appropriate countermeasures” for several months and that it aims to “bring the risk of an incident back to the security level equal to that of a standard operating day”, it also cautioned that “the risk of incident cannot be completely ruled out”, and that any such incident could be “serious”.

The group said the eclipse would be “an unprecedented test for Europe’s electricity system”.

When Europe last saw a solar eclipse in 1999, the bloc derived a mere 0.1 per cent of its power from the sun. This amount has now grown to around 10.5 per cent, with around 90 GW of solar photovoltaic capacity installed.

According to ENTSO-E’s Solar Eclipse Impact Analysis, operational co-ordination among European TSOs will be crucial to avoiding power disruption. The group said TSOs will co-ordinate control rooms across Europe ahead of and during the eclipse in order to provide fast response in case of power outages. The main challenge for TSOs, it said, will be to co-ordinate use of reserves in order to balance power in real time without overloading the grid.  

“The solar eclipse is a perfect illustration that maintaining system security with more and more volatile and dispersed generation is becoming increasingly challenging,” ENTSO-E said.

The eclipse’s expected path across Europe can be seen here in a video from MeteoSwiss.  

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