Lessons from the first blackout of the green era

Over 50 million people were affected, raising questions about the resilience of renewable energy networks.

- Javier Blas

Over a century of running the power grid on fossil fuels, we learnt many lessons about why, how and when blackouts happen. We now need to learn new lessons about when they're triggered by green energy.

On April 28, Spain and Portugal—and a sliver of France—suffered what could come to be known as the first major blackout of the renewable-energy era. More than 50 million people lost power, and electricity didn't return for nearly half a day.

We don't yet know the full details, but Red Electrica de Espana, Spain's state-backed grid operator, detailed the next day a tentative timeline of the massive disruption. The company suspects that an initial power failure was "very likely" due to a solar plant producing less than expected, and seconds later there was a "massive" drop in other renewable-electricity production.

Left unsaid is another critical factor: Spain and Portugal were running their grid with a generation mix that relied heavily on the weather—for more than 75 per cent of output. Few of the old-fashioned generators powered by gas, nuclear and hydraulic force, which are key to ensuring a stable grid, were running.

The Spanish and Portuguese authorities have promised a root-cause analysis of the incident, and the lessons should be heeded around the world as most countries embrace solar and wind power—though perhaps not as aggressively as the Iberian nations.

The authorities need to focus on how to better integrate growing renewable production into the grid to strengthen resilience, rather than retreat from and dismantle net-zero generation.