Medium Fuel Oil litres kWh/litre Heavy Fuel Oil litres kWh/litre Propane kg kWh/kg Butane kg kWh/kg Dry steam coal tonnes 8,500 kWh/tonne Anthracite tonnes 8,236 kWh/tonne Coke tonnes 7,750 kWh/tonne Nitrogen hcum kWh/hcum Carbon dioxide hcum kWh/hcum Steam kg Depends on conditions.