Chemical fuels are dramatically easier to store and transport than electricity. Batteries are heavy and expensive compared to a tank. Time-dependent surplus ele

Chemical fuels are dramatically easier to store and transport than electricity. Batteries are heavy and expensive compared to a tank. Time-dependent surplus electricity (which is basically a guaranteed situation on renewable-heavy grids) is basically free, which makes efficiency concerns approximately moot. Instead of letting excess capacity go to waste, you use it to create chemical fuel, which can be used either just as storage to be later burned in a peaker plant, or you can use it as fuel in mobile settings (trucks, planes, ships, etc) where energy density is important.