Having worked in a steel mill that ran two to three arc furnaces concurrently, I was curious as to how much power they consumed. I grabbed the following from wikipedia:iwire said:
"A mid-sized modern steelmaking furnace would have a transformer rated about 60,000,000 volt-amperes (60 MVA), with a secondary voltage between 400 and 900 volts and a secondary current in excess of 44,000 amperes. In a modern shop such a furnace would be expected to produce a quantity of 80 metric tonnes of liquid steel in approximately 60 minutes from charging with cold scrap to tapping the furnace. In comparison, basic oxygen furnaces can have a capacity of 150-300 tonnes per batch, or 'heat', and can produce a heat in 30-40 minutes. Enormous variations exist in furnace design details and operations, depending on the end product and local conditions, as well as ongoing research to improve furnace efficiency - the largest scrap-only furnace (in terms of tapping weight and transformer rating) is in Turkey, with a tap weight of 250 metric tonnes and a transformer of 240 MVA.
To produce a ton of steel in an electric arc furnace requires on the close order of 400 kilowatt-hours per short ton of electrical energy, or about 440kWh per metric tonne; the theoretical minimum amount of energy required to melt a tonne of scrap steel is 300kWh (melting point 1520?C/2768?F). Electric arc steelmaking is only economical where there is a plentiful supply of electric power, with a well-developed electrical grid."
To produce a ton of steel in an electric arc furnace requires on the close order of 400 kilowatt-hours per short ton of electrical energy, or about 440kWh per metric tonne; the theoretical minimum amount of energy required to melt a tonne of scrap steel is 300kWh (melting point 1520?C/2768?F). Electric arc steelmaking is only economical where there is a plentiful supply of electric power, with a well-developed electrical grid."