Power is almost fully restored in Spain and Portugal a day after a major blackout. MADRID (AP) — The cause of Spain and Portugal's widespread blackouts remained a mystery on Tuesday, with some isolated disruption remaining after power was largely restored to both countries.

Even as electricity was restored across Spain and Portugal after a daylong blackout, residents tried to make sense of 18 hours of the “insanity.”

As factories, stores and hotels across Spain and Portugal gradually returned to normal on Tuesday after a huge blackout the day before, business associations and companies began counting the cost.