And the same concept as pumped hydro can by applied in other ways that don't require a waterway or quite as much physical infrastructure, https://www.vox.com/20

And the same concept as pumped hydro can by applied in other ways that don't require a waterway or quite as much physical infrastructure, https://www.vox.com/2016/4/28/11524958/energy-storage-rail https://www.vox.com/2016/4/28/11524958/energy-storage-rail is an example.