How Big a Battery Would It Take to Power All of the U.S.?: I enjoyed this article which confirms something I’ve always believed: the secret to a renewable energy future is battery technology. The problem with solar and wind is that they’re intermittent. – clouds and calm become issues.
Experts, however, are increasingly skeptical that even supergrids or smart grids would suffice to cover the intermittency of wind and solar power. The solution, they say, must include storing massive amounts of energy for later use. Ideally, the U.S. could build a really gigantic battery and be done with it. But we are talking gigawatts (billions of watts) of power, and such a battery would be prohibitively expensive, at least with current technology.
But if you can buffer power and overcome this, the results would be spectacular. As the article says: “The U.S. Southwest’s deserts get enough sunlight to sustain the country’s thirst for electricity—20 times over.”
I love the idea of the pumped hydro facility. It’s like a caveman battery, on a massive scale.
A pumped-hydro facility consists of two reservoirs with a substantial drop in height between them. When there is excess electricity to go around, electric pumps move water from the lower reservoir into the upper one, thereby storing energy in the form of gravitational potential energy. When wind and solar wane or simply cannot keep up with demand, operators let water flow down and through turbines, generating electricity.