# What is the Coimbatore air compressor cluster's energy use and carbon footprint?

Canonical: https://senseible.earth/answers/coimbatore-compressor-makers-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.

- [Carbon calculators](https://senseible.earth/calculators)
- [Coimbatore pump cluster footprint](https://senseible.earth/answers/coimbatore-pump-cluster-carbon-footprint)
- [Coimbatore foundry energy per tonne](https://senseible.earth/answers/coimbatore-foundry-cluster-energy-per-tonne-castings)

Sources: [TERI, Energy profile: Coimbatore compressor cluster](https://sameeeksha.org/pdf/clusterprofile/Coimbatore-Compressor-Cluster.pdf), [IPCC 2006 Guidelines, Volume 2 Energy (fuel emission factors)](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html), [CEA, CO2 Baseline Database for the Indian Power Sector (grid factor 0.675 kg CO2 per kWh, FY 2025-26)](https://cea.nic.in/cdm-co2-baseline-view?mappingId=234&lang=en)

Last reviewed 2026-10-31.