Experts differ on the reasons for the blackout

While Red Eléctrica, the operator of the Spanish electricity grid, says that the causes of the blackout have not yet been clarified, some experts believe that the collapse of the Spanish and Portuguese grids is linked to the very high level of solar production and the lack of conventional back-up power stations at the time when the grid collapsed. 55% of electricity production came from solar photovoltaic installations at the time of the blackout. Opinions differ, however, as to how solar production could have caused the grid to collapse. For some experts, solar production was excessive; for others, on the contrary, it was a cloudy spell over a geographical area with a large number of photovoltaic installations that caused production to fall suddenly, leading to the collapse of the grid. For Red Eléctrica, the importance of renewable energy sources does not increase the vulnerability of the network.