Spanish blackout report: Power plants meant to stabilize voltage didn’t

The blackout that took down the Iberian grid serving Spain and Portugal in April was the result of a number of smaller interacting problems, according to an investigation by the Spanish government. The report concludes that several steps meant to address a small instability made matters worse, eventually leading to a self-reinforcing cascade where high voltages caused power plants to drop off the grid, thereby increasing the voltage further. Critically, the report suggests that the Spanish grid...