How big is the Kolhapur foundry cluster's carbon footprint, and how many units already melt on induction?

About 1.2 million tonnes of CO2 a year, an estimate from the 1,185 million kWh and 128,111 tonnes of coke TERI recorded for Kolhapur. About 70% of its roughly 300 foundries melt on induction. On grid power, induction melting is not lower carbon than a cupola yet.

The cluster's energy

• About 300 foundries: 250 to 275 in Kolhapur district across eight industrial areas, and 20 to 25 in Miraj and Palus in Sangli.
• About 600,000 tonnes of grey and SG iron castings a year, roughly 7% to 8% of India's output, with about 30% exported.
• 1,185 million kWh of electricity and 128,111 tonnes of coke a year, from a 2012 study. Energy is 15% to 20% of the cost of a casting.
• About 70% of foundries melt in induction furnaces and 30% in cupolas. SG iron work is pushing the shift.

In tonnes of CO2

Electricity gives about 800,000 tonnes and coke about 387,000, so roughly 1.19 million tonnes a year. Do not divide that by 600,000 tonnes and call it a benchmark. The energy and tonnage come from different estimates, and the result, about 1,975 kWh a tonne, sits far above the 1,000 to 1,200 kWh per tonne of good castings that induction units report. Your own bills are the only defensible figure.

Why the induction shift has not cut CO2 yet

Kolhapur induction units use 600 to 700 kWh a tonne to melt. A cupola runs at a coke to metal ratio of 1:8 to 1:9. On today's grid factor, induction melting emits slightly more per tonne of metal than a cupola. Units switch for SG iron quality. To win on carbon, induction needs cleaner power: even the temperature, frequency and harmonic-loss fixes TERI points to would have to bring melting near 500 kWh a tonne (about 338 kg CO2) just to match a cupola at 1:9.

Buyers, CBAM and the melt log

• Tractor, engine and auto buyers, in India and abroad, ask for kg CO2 per tonne of good castings.
• CBAM covers cast pipe fittings under CN 7307, but most machine castings sit outside it. Check each export code.
• Lenders for furnace upgrades want kWh per tonne before and after.
• Keep a melt log (kWh or coke per heat), monthly power bills, coke invoices, and good castings despatched, not metal poured.

Worked example: melting only, per tonne of metal

• Induction at 600 kWh: 600 x 0.675 = 405 kg CO2
• Induction at 700 kWh: 700 x 0.675 = 473 kg CO2
• Cupola at 1:8 coke: 125 kg coke x 3.02 = 378 kg CO2
• Cupola at 1:9 coke: 111 kg coke x 3.02 = 336 kg CO2
• Whole induction unit at 1,100 kWh per tonne of good castings: 1,100 x 0.675 = 743 kg CO2

Estimates. Coke at 3.02 t CO2 per tonne is the IPCC 2006 default for coke oven coke; Kolhapur coke at 5,500 to 6,500 kcal per kg may differ. Grid factor for FY 2025-26.

What Senseible does here

Senseible reads power bills and coke invoices into a dated monthly record for the foundry, each line traced to its bill. Add your good castings despatched and you have the evidence behind the kg CO2 per tonne buyers ask for.

• Your carbon number for buyers and banks
• What buyers ask Kolhapur foundries for
• Are cast iron castings covered by CBAM?
• Green loan for a Kolhapur foundry

Sources: TERI, Cluster profile report: Kolhapur foundry cluster (SAMEEEKSHA)-Cluster.pdf), IPCC 2006 Guidelines, Volume 2 Energy, CEA CO2 Baseline Database, version 22.0, CBAM Regulation (EU) 2023/956, consolidated, Annex I

Last reviewed 2026-10-29. Cluster energy is from a 2012 study quoted in TERI's profile. Update if a newer Kolhapur profile is published.