What does moving brass melting from a coke pit furnace to a 500 kg induction furnace do to CO2?

CO2 falls by about 166 kg for every tonne of brass melted, on today's grid. BEE's Jagadhri report has a pit furnace burning 80 kg of coke per 600 kg melt and a 500 kg induction furnace using 175 kWh per melt. Cost Rs 17.05 lakh, payback 1.67 years at 2010 prices.

The two furnaces in the report

• Pit furnace: a crucible in a refractory-lined pit with coke packed under and around it, 600 kg a melt, 4 to 5 melts a day, about two and a half hours each.
• 80 kg of coke a melt, with about 20 kg left unburnt at the end. Flue gas at 500 to 550 C; efficiency 8 to 12%.
• Induction: 500 kg a melt, 175 kWh, 5 melts a day for 300 days, 262,500 kWh a year.
• At Rs 22 a kg of coke and Rs 4.5 a kWh, the saving is Rs 1,359 a tonne and Rs 10.19 lakh a year.

Per tonne is the fair comparison

The report sets 120 t of coke a year against 262,500 kWh, but the coke total is for 600 kg melts and the power for 500 kg melts. Compare per tonne: 133 kg of coke against 350 kWh. On the report's yearly totals the cut is about 185 t; for the same 750 t of brass it is about 125 t. The report's 114 t used older factors.

Checks that change the answer

• Unburnt coke: if the 20 kg left in the pit goes into the next melt, real coke use is 100 kg a tonne and the CO2 cut falls to about 66 kg a tonne.
• Power supply: induction melting needs continuous supply, so check outages and your contract demand.
• Weigh coke per melt for a month before you compare.

Per tonne of brass melted

• Pit furnace: 80 / 0.6 = 133 kg coke x 3.02 = 403 kg CO2
• Induction: 175 / 0.5 = 350 kWh x 0.675 = 236 kg CO2
• Saved: about 166 kg CO2 a tonne
• On 750 t a year: about 125 t CO2

Coke at the IPCC 2006 default (107,000 kg CO2 per TJ at 28.2 GJ per tonne) and grid at CEA's FY 2025-26 factor, both estimates.

What Senseible does here

Senseible reads coke invoices and electricity bills into monthly records linked to each bill, with CO2 for the power. It has no built-in coke factor, so apply the one worked above to the coke tonnes. The green loan check shows what a lender asks for on a furnace loan.

• Green loan readiness check
• Oil crucible or induction for brass
• Jagadhri brass and aluminium cluster
• Brass: coal pit to gas rotary furnace

Sources: BEE, Detailed project report: induction furnace for brass melting, 500 kg, Jagadhri brass and aluminium cluster (2010, SAMEEEKSHA), IPCC 2006 Guidelines, Volume 2 Energy, Tables 1.2 and 2.3, CEA CO2 Baseline Database, version 22.0

Last reviewed 2026-10-31. Report figures are from a BEE SME programme project report; costs and paybacks are at the report year's prices. Check today's fuel and power prices before you rely on the payback.