Does an infrared thermometer at the furnace actually save energy in a foundry?

Yes, a little, and only if the operator cuts power when the display reads target. BEE's Punjab foundry report has melts overshooting 1,460 C to beyond 1,480 C. Stopping that saves about 5 kWh a tonne: 10,000 kWh and Rs 0.50 lakh a year on 2,000 t. Cost Rs 0.46 lakh, payback 0.92 years.

Why melts run too hot

Iron is needed at about 1,460 C for casting. Operators check it with a contact thermocouple every so often and, fearing cold metal and bad castings, let it climb past 1,480 C to cover the drop during transfer. Between dips the furnace keeps drawing power. An infrared pyrometer reads the bath continuously on a display about 2 ft by 1 ft that the operator can see from the panel.

The foundry in the report

• 8.32 t of charge a day, 8 t of good metal, 250 days: 2,000 t a year.
• Power: 5,990 kWh a day, about 0.72 kWh per kg melted, at Rs 5 a kWh.
• After the pyrometer: 5,949 kWh a day, about 5 kWh a tonne less.
• Saving: 10,000 kWh, Rs 0.50 lakh a year.

What it costs

• Pyrometer and display Rs 25,000, tax Rs 3,125, civil Rs 3,000, fitting Rs 5,000, other Rs 10,000: Rs 46,125.
• Payback 0.46 / 0.50 = 0.92 years, about 11 months.
• Five days set aside for fitting.

What makes the saving real

1. Write the tapping temperature for each grade on the panel.
2. Train every shift to switch off or drop power at that reading, not when the clock says so.
3. Keep the lens clean and check the reading against a dip thermocouple each week; slag and fumes throw an infrared reading off.
4. Log kWh per tonne tapped for a month before and after.

One furnace, one year (estimate)

• 5 kWh x 2,000 t = 10,000 kWh saved
• CO2: 10,000 x 0.675 = 6.75 t
• The report's 8.1 t uses an older grid factor of 0.81
• Daily check: (5,990.4 minus 5,948.8) / 8 t = 5.2 kWh a tonne

CO2 at CEA's FY 2025-26 grid factor of 0.675 kg per kWh.

What Senseible does here

Senseible's calculators turn the kWh saved into CO2 on the current grid factor, and it reads monthly electricity bills into records you can set against tonnes melted to show kWh per tonne falling.

• Carbon calculators
• Induction furnace kWh meter and integrator
• Medium or mains frequency induction furnace
• Arc furnace to medium frequency induction

Sources: BEE, Detailed project report: energy cost reduction with infrared thermometer, Batala, Jalandhar and Ludhiana foundry cluster (SAMEEEKSHA), CEA CO2 Baseline Database, version 22.0

Last reviewed 2026-11-01. Report figures are from a BEE SME programme project report; costs and paybacks are at the report year's prices. Check today's tariff and a current quote.