Published on
10/08/2026 - 16:38 GMT+2
Portugal's grid operator Redes Energéticas Nacionais (REN) expects it will have to tap additional energy reserves to offset the loss of solar power generation caused by Wednesday's eclipse.
In the statement REN published on its website this Monday (source in Portuguese), the company says that "additional reserves from hydro and/or thermal generation will have to be mobilised" to mitigate the impact the phenomenon will have on the balance between energy consumed and generated in the National Electricity System (SEN), as well as the deviations the eclipse will cause in the interconnection between the Portuguese and Spanish grids. In neighbouring Spain, the eclipse will be 100% in a large part of the territory, while in Portugal it will be "almost total", ranging from 92% in the Algarve to 100% in the municipality of Bragança. The village of Guardamil is considered the best place in Portugal to see the eclipse in full.
According to REN's statement, the phenomenon, which will occur between 18:30 and 20:30 on Wednesday 12th, "will lead to an estimated loss of solar generation of 450 MW", which will represent around 7% of consumption and 45% of the solar output of the National Electricity System forecast for this time slot (average values). REN further indicates that "compared with the peak solar output forecast, the impact of the eclipse is estimated at around 15%".
