Like other parts of the US rushing to transition away from fossil fuels, the Pacific Northwest’s grid is increasingly reliant on wind farms like this one, in addition to solar arrays. That’s great when the wind blows and the sun shines, but as anyone who has walked the drizzly streets of Seattle can attest, you can’t always count on that. To guarantee a smooth, carbon-free supply of electricity despite this variability, the grid requires enormous amounts of energy storage, and projections indicate that the region needs up to 10,000 megawatts of backup reserves to meet 100-percent renewable power goals.
Renewable energy needs pumped hydro storage
