The vast majority of our grid-scale storage of electricity uses this clever method. Electricity faces a fundamental problem that comes with pretty much any product that’s provided on-demand: our ability to generate large amounts of it doesn’t match up that closely with when we need it. The storage of electricity for later use, especially on a large scale, is quite challenging. That’s not to say that we don’t store energy at grid scale though, and there’s one type of storage that makes up the vast majority of our current capacity.
