# What calorific value does India use for natural gas per SCM?

Canonical: https://senseible.earth/answers/india-natural-gas-gcv-10000-kcal-per-scm

PPAC's gas conversions, sourced from GAIL, use a gross calorific value of 10,000 kcal per SCM, with net calorific value at 90% of that. One MMBtu equals 25.2 SCM on this basis. Domestic production averages 8,000 to 9,480 kcal per SCM, so use the GCV on your own bill when it is printed.

## The reference values

- 1 SCM = 1 cubic metre at 1 atmosphere and 15.56 C.
- Gross calorific value: 10,000 kcal per SCM. Net calorific value: 90% of GCV.
- 1 MMBtu = 25.2 SCM at 10,000 kcal per SCM; 1 MMBtu = 252,000 kcal.
- Density of gas: 0.76 kg per SCM; specific gravity 0.62.
- Average natural gas production in India: 8,000 to 9,480 kcal per SCM (Table 9.1).

## From SCM to CO2

1. Multiply SCM by the GCV on your bill, or 10,000 kcal if none is printed.
2. Take 90% for net calorific value and convert to GJ (1 kcal = 4.19 kJ per PPAC).
3. Multiply by the IPCC natural gas default of 56.1 kg CO2 per GJ.

## Why your figure may differ

On these PPAC values one SCM works out to about 2.12 kg CO2, while 0.76 kg per SCM times the IPCC per-kg factor gives about 2.05. The two reference values imply slightly different gas. A bill that prints GCV settles it for your supply.

## Worked example

- 1,000 SCM x 10,000 kcal = 10,000,000 kcal GCV.
- NCV = 9,000,000 kcal x 4.19 kJ = 37.71 GJ.
- CO2 = 37.71 x 56.1 = 2,116 kg.

Uses PPAC reference values, not a specific bill.

## What Senseible does here

Senseible reads the quantity and unit printed on each fuel invoice, converts it with a stated density or calorific value, and shows the factor and source on every line, so a litre or kilogram is never guessed.

- [PNG bill in MMBtu to CO2](https://senseible.earth/answers/png-bill-mmbtu-to-co2)
- [GCV vs NCV in fuel calculations](https://senseible.earth/answers/gcv-vs-ncv-in-fuel-emission-calculation)
- [SCM vs Nm3](https://senseible.earth/answers/natural-gas-scm-vs-nm3-conversion)

Sources: [PPAC Ready Reckoner FY 2025-26, Chapter 9 conversion tables](https://ppac.gov.in/download.php?file=rep_studies/1784899305_The_PPAC_Ready_Reckoner_FY_2025%E2%80%9326_Final.pdf), [IPCC 2006 Guidelines, Volume 2 (Energy), default factors](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html)

Last reviewed 2026-10-23.