Lisbon, March 28, 2025 (Lusa) - The partial solar eclipse that will take place for two hours on Saturday morning will cause a 23% reduction in the National Electricity System's production scheduled for that time, REN - Redes Energéticas Nacionais said on Friday.

"The phenomenon will occur in mainland Portugal between 9.30 a.m. and 11.30 a.m. and will cause an estimated loss of generation of 560 MW [megawatts], which represents around 8.5% of consumption and 23% of the production of the National Electricity System scheduled for this time," REN said in a statement.

The company said that, in collaboration with the other transmission system operators in the European electricity sector, it has been preparing the National Electricity System (SEN) for the effects of the eclipse that will take place on Saturday.

The phenomenon, in which the moon will partially cover the sun for two hours, will be visible throughout mainland Portugal.

During the eclipse, REN estimates a loss of 10 MW per minute and a recovery at the rate of 22 MW per minute, "which will cause operational challenges related to the balance between generation and consumption in the SEN and to controlling the deviation in the interconnection with Spain".

Therefore, he explained, allocating additional reserves with hydro and/or thermal generation will be necessary.

These estimated figures do not consider the solar production associated with some self-consumption production units, which will also affect the increase in consumption, REN emphasised.

"This effect is also being estimated by REN and duly provided for in the consumption forecasts for that day, in order to reduce and mitigate the unexpected effects in real time," it said.

MPE/ADB // ADB.

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