# How much CO2 does a Khurja pottery unit save moving its kiln from coal to gas?

Canonical: https://senseible.earth/answers/khurja-pottery-coal-to-gas-saving

Per unit of heat, natural gas emits about 40% less CO2 than bituminous coal under IPCC defaults: 56.1 against 94.6 kg CO2 per GJ. The real saving also depends on kiln efficiency, so compare fuel bills before and after for the same output.

## The comparison

- Coal (other bituminous): 94.6 kg CO2 per GJ (IPCC 2006 default).
- Natural gas: 56.1 kg CO2 per GJ.
- Saving per GJ: 1 minus 56.1 / 94.6, about 40.7%.

## Check it

A gas kiln often fires more efficiently, which adds to the saving. Use measured fuel per tonne fired before and after, not the factor alone.

## Worked example: same heat (illustrative quantity)

- Heat needed: 258 GJ (about 10 t of coal at 25.8 GJ per t)
- Coal: 258 x 94.6 = 24,407 kg CO2
- Gas: 258 x 56.1 = 14,474 kg CO2
- Saving: 24,407 minus 14,474 = 9,933 kg CO2

Heat demand is illustrative and assumes equal kiln efficiency.

## What Senseible does here

Senseible reads electricity bills (CEA grid factor 0.710 kg CO2 per kWh, CO2 Baseline Database version 21.0) and diesel, LPG and gas invoices (IPCC 2006 defaults) into a dated, fingerprinted Scope 1 and 2 record for each site. Intensity per unit uses the activity count you enter, and estimates are labelled as estimates.

- [Pottery kiln emissions per firing](https://senseible.earth/answers/pottery-kiln-emissions-per-firing)
- [Coal vs PNG vs biomass](https://senseible.earth/answers/coal-vs-png-vs-biomass-boiler-emissions)
- [Morbi gasifier vs piped gas](https://senseible.earth/answers/morbi-coal-gasifier-vs-piped-gas-kiln-co2)

Sources: [IPCC 2006 Guidelines, Volume 2 Energy](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html)

Last reviewed 2026-10-21.