For this application? Pumped hydro, high temperature thermal in firebrick (a technology used by the steel industry in the 1920s), and hydrogen.
Also, adapt iron/steel production to use direct electrolytic methods, although that's going to require more R&D. The potential for dispatchability of demand is enormous.
Also, adapt iron/steel production to use direct electrolytic methods, although that's going to require more R&D. The potential for dispatchability of demand is enormous.