Spain’s power grid failed in mere seconds, blacking out the entire country and parts of Portugal. It was a stunning collapse that illustrates an inviolable law of the electric system: The heartbeat of the grid — known as frequency — must be stable at all times.
With more renewables on the grid and an ever-greater reliance on electricity to power everything from cars to heat pumps, the chances of that heart skipping a beat are rising. That has grid operators racing to find solutions to avoid the next Spain-sized blackout — and they’re increasingly turning