Does cutting scrap to size before charging really cut induction furnace power?
Yes, in TERI's June 2026 Raipur case. A unit with five 8 t furnaces added a scrap shearing machine; melting time fell from 37 to 22 minutes and energy per heat from 944 to 561 kWh, saving about 40.1 lakh kWh and Rs 2.4 crore a year on a Rs 1.8 crore machine.
Why loose scrap costs power
Scrap of every shape and size was going straight into the crucibles, and TERI found that was the main reason heats ran long. Bulky, uneven pieces pack loosely, so the charge takes longer to melt down while the furnace keeps losing heat through its walls and open top. Cut into small, even pieces, the scrap packs densely and each heat finishes sooner.
The case in numbers
- Five induction furnaces of 8 t design capacity, charged with scrap and sponge iron.
- Average scrap melting time: 37 minutes before, 22 after.
- Energy per heat cycle: 944 kWh before, 561 after.
- Saving: about 40.1 lakh kWh a year and Rs 240 lakh; machine cost Rs 180 lakh, a nine month payback.
Read the 944 and 561 with care
The newsletter calls 944 kWh per tonne of liquid metal in its text and per heat in its table, and 561 per heat. Taken per tonne, 561 would be close to the 550 an efficient IGBT furnace reaches, which is unusual for sheared scrap alone. The 40.1 lakh kWh saving is the firmer figure. When you trial shearing, compare kWh per tonne tapped on a dedicated furnace meter, before and after, at the same charge mix.
Before you buy a shear
- Sort a week's scrap receipts by type: bundles, heavy melting scrap, turnings, structural offcuts.
- Time a set of heats with each charge type and note kWh per tonne.
- If loose, light scrap gives the longest heats, a shear or baler pays first; if your charge is mostly sponge iron, the gain is likely to be smaller.
The Raipur shear, CO2 a year (estimate)
- Saving: 40.1 lakh kWh x 0.675 kg = 2,707 t CO2 a year
- TERI reported 3,173 t at an older grid factor
- Money per kWh saved: Rs 240 lakh / 40.1 lakh kWh = about Rs 6
Case data from the SAMEEEKSHA newsletter, June 2026 (TERI). The unit is not named in the source. CEA FY 2025-26 grid factor. Electricity is outside CBAM's count for iron and steel goods, so this lowers your footprint, not a billet's CBAM figure.
What Senseible does here
Senseible reads monthly power bills into CO2 per tonne melted, so a trial like this shows up in your records month by month, ready for a green loan file.
Sources: SAMEEEKSHA newsletter, June 2026: secondary steel case studies (TERI).pdf), CEA, CO2 Baseline Database for the Indian Power Sector, version 22.0
Last reviewed 2026-11-01.