Melts metals via a powerful electric arc. The arc is deployed using graphite anodes that are partially spent during the process due to the high heat. Beware that the furnace consumes a significant amount of power. It would be polite to notify your local power plant before turning this on.
Thermal storage uses steam to heat its tank of molten salt to store thermal energy. The accumulated energy can be then used to boil incoming water back to steam. The conversion process has losses but maintaining the accumulated heat does not decay while the storage is operational.
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