The SHARC is the most efficient scrap preheating design for electric arc furnaces. Equipped with two vertical preheating shafts (conventional systems use only one asymmetric shaft), the entire furnace cross-section over the height of the two shafts is available for energy transfer. This is made possible by the symmetrical shape of the furnace and the integration of DC high-current technology. The longer retention time of the hot exhaust gases in contact with the scrap results in energy savings of up to 100 kWh/t less than conventional furnaces.