How much fuel or electricity per tonne should a forging furnace use?
BEE's energy conservation guidelines for MSMEs give 70 to 100 litres of fuel per tonne for fuel-fired forging furnaces and 400 to 600 kWh per tonne for induction forging furnaces. Divide a month's fuel or metered kWh by the tonnes you heated to see where you stand.
How to calculate
- Fuel-fired: litres of fuel used in the period / tonnes of material heated. For kcal per tonne, multiply fuel kg by its calorific value first.
- Induction: kWh from a dedicated meter on the furnace / tonnes heated. BEE asks for a meter reading every batch.
Other targets for fuel-fired furnaces
- Air ratio: 1.15 to 1.20 on liquid fuel, 1.12 to 1.15 on natural gas
- Waste heat recovery: target 49% of the heat in exhaust gas at 600 to 1,000 °C, leaving flue gas at 250 to 300 °C
- Skin temperature: target 110 °C on the ceiling and 85 °C on side walls
- Induction furnace skin: target 70 °C
Where the extra fuel goes
- Excess air and cold air leaking in through openings and poor seals
- Hot walls from thin or damaged insulation
- Exhaust heat that no recuperator recovers
- Holding the furnace hot while the press waits
Example: an oil-fired forging furnace (illustrative)
- Furnace oil used in the month: 9,000 litres
- Steel forged: 100 tonnes
- 9,000 / 100 = 90 litres per tonne, inside the 70 to 100 range but near the top
Figures are illustrative; use your own logbook and weighbridge records.
What Senseible does here
Senseible reads your fuel invoices and electricity bills into monthly energy totals. Add your production figures and you get energy per tonne to set against these benchmarks, month after month.
Sources: BEE, Energy Conservation Guidelines for MSME Sector (2019): section 6.2, Tables 6.8 to 6.11 and 6.14
Last reviewed 2026-10-24.