What is the Coimbatore air compressor cluster's energy use and carbon footprint?
An assembler's footprint is its power bill, about 50 kWh per compressor. A component maker with a paint oven is different: LPG and diesel are over 80% of its CO2. The 300 or so units used 2,255 toe in 2017-18, roughly 9,600 t CO2.
Two kinds of unit
- 100 assemblers build about 57,000 reciprocating compressors a year: 10 medium units at about 250 a month, 60 small at 30, 30 micro at 15.
- Small units build up to 5 hp, medium units up to 20 hp. None of the MSMEs makes screw compressors.
- 200 component makers supply foundation plates, engine cases, pistons, air receivers, sheet metal parts and connecting rods; castings and forgings come from the city's foundries and forges.
Where the energy goes
- Machining takes about 80% of a unit's electricity, welding 10% and the shop's own air compressors 5 to 10%.
- Component units cure paint in LPG or diesel ovens at about 200 C, 500 kg to 5 t a batch for 45 to 60 minutes. Ovens are often oversized and run part empty.
- Diesel also runs DG sets in the rare power cuts.
Most of a compressor's footprint is bought in
An assembler's own power is about 34 kg CO2 per compressor. The castings, steel and motor in it weigh far more in a product figure. Those are Scope 3 purchased goods: ask each supplier for a per kg or per part figure and keep the reply with the order.
Quick wins
- Insulate paint ovens and cut the heated volume to match the load.
- Cogged V-belts at 95 to 98% transmission efficiency, against 90 to 92% for flat belts.
- IE3 motors on lathes and honing machines, and plugged air leaks.
Unit and cluster figures (estimate)
- Assembler: 28,800 kWh x 0.675 = 19.4 t CO2 a year
- Per compressor: 2.88 million kWh / 57,000 = 50.5 kWh x 0.675 = 34 kg CO2
- Typical component unit with a paint oven: 26,000 kWh = 17.6 t; 16,364 kg LPG x 2.98 = 48.8 t; 13,043 L diesel x 2.645 = 34.5 t; total 100.8 t
- Cluster: 8.08 million kWh = 5,454 t; 818 t LPG = 2,438 t; 652 kL diesel = 1,725 t; about 9,600 t
Energy and output from TERI's 2017-18 cluster energy profile; factors from CEA and IPCC. Castings, steel and motors bought in are not included.
What Senseible does here
Enter your kWh, LPG and diesel in the calculators to see which one drives your figure; Senseible can read the gas, fuel and power bills themselves into monthly records once you need them on file.
Sources: TERI, Energy profile: Coimbatore compressor cluster, IPCC 2006 Guidelines, Volume 2 Energy (fuel emission factors), CEA, CO2 Baseline Database for the Indian Power Sector (grid factor 0.675 kg CO2 per kWh, FY 2025-26)
Last reviewed 2026-10-31.