April 16: The first weekday that Spain’s electrical grid ran 100% on all renewables;
April 21: Solar energy output set a new record, 78.6% of demand and 61.5% of the grid mix;
April 28: the entire grid went down, taking Portugal’s national grid with it.
Without any explanation, the Spanish Energy Ministry simply reported that around 10:33 GMT, in a span of five seconds, generated electricity dropped by 15 GW; there were other oscillations and the entire system was shut down, and not fully restored for about 24 hours.