Naturally the sustainable energy transition will actually end up costing less than continuing on the current path of fossil fuel investment and subsidies ($10 Trillion vs. $14 Trillion), and the grid will require about half the total generation (82 PetaWatt-hours / yr compared to 165 PetaWatt-hours / yr) due to the vastly greater efficiency of renewables.

Batteries soak up electricity when there's a surplus and redistribute it when needed, and as such are an essential part of the new-age grid being built today.

Tesla have been working on this problem for a while and already have many successful stationary battery packs deployed around the world, contracted by businesses or governments for mega installations.