Denmark is now home to one of the most powerful and innovative battery systems in the world—a 1 GWh molten salt battery that can power 100,000 homes for 10 hours. Developed by Hyme Energy and Sulzer, the system uses molten hydroxide salts—an industrial byproduct—to store renewable electricity as ultra-high-temperature heat. With up to 90% efficiency, this new energy storage tech could revolutionize grid stability and industrial decarbonization.