Unprocessed Natural Gas
Reviewed by Afonso Firmo, Co-Founder & Director · Updated 7 July 2026
Unprocessed natural gas has a Scope 1 emission factor of 51.53 kg CO₂-e/GJ under NGA Factors 2025. Worked examples and calculator for upstream operators.
Emission Factor Value
51.53 kg CO₂-e/GJ
Try it with your own numbers
Estimated emissions
—
Combustion of unprocessed natural gas is reported under Scope 1 at 51.53 kg CO₂-e/GJ (NGA Factors 2025, Table 5). Cubic metres are converted at a default energy content of 0.0393 GJ/m³ — use measured gas composition where available under NGER methods.
Official Source & Citation
This emission factor is sourced from the Australian National Greenhouse Accounts Factors 2025 , Table 5 — Gaseous fuels including liquefied natural gas, published by the Department of Climate Change, Energy, the Environment and Water (DCCEEW).
Citation: DCCEEW (2025). Australian National Greenhouse Accounts Factors 2025. Commonwealth of Australia. Available at: https://www.dcceew.gov.au/climate-change/publications/national-greenhouse-accounts-factors-2025
Notes
Combined Scope 1 factor of 51.53 kg CO₂-e/GJ = CO₂ 51.4 + CH₄ 0.1 + N₂O 0.03 (NGA Factors 2025, Table 5). Energy content 0.0393 GJ/m³. 1 GJ of unprocessed natural gas combusted = 51.53 kg CO₂-e. Applies to raw gas combusted before processing, typically as fuel gas at upstream facilities.
Calculation Example
If your gas processing facility combusted 12,000 GJ of unprocessed gas as fuel:
| Working | Result |
|---|---|
| 12,000 GJ × 51.53 kg CO₂-e/GJ = 618,360 kg CO₂-e | 618.36 tonnes CO₂-e (Scope 1) |
Upstream oil and gas facilities largely run on their own product: raw gas drawn off before processing fuels the compressors, heaters and generators that keep a field operating. That fuel gas is a direct combustion source, and it lands squarely in your Scope 1 inventory alongside flaring and fugitives.
This entry gives the NGA Factors 2025 combustion factor for unprocessed natural gas, three worked examples, and the boundaries between combustion, venting and flaring that trip up new reporters.
Quick Verdict
Unprocessed natural gas has a combined Scope 1 emission factor of 51.53 kg CO₂-e per gigajoule under the NGA Factors 2025 (Table 5) — 51.4 kg CO₂ plus small CH₄ and N₂O components, at a default energy content of 0.0393 GJ/m³. The factor applies to raw wellhead or gathering-system gas combusted before processing, which in practice means fuel gas at upstream oil and gas facilities. Combustion is reported under Scope 1 by the operator; venting and flaring are separate source categories with their own NGER methods. If your organisation operates gas-producing assets, this factor covers the fuel-gas line of your Scope 1 calculation for 2025–26.
How to Calculate Unprocessed Natural Gas Emissions
Emissions (kg CO₂-e) = Energy consumed (GJ) × 51.53 kg CO₂-e/GJ
Convert metered cubic metres at the default 0.0393 GJ/m³, or use measured energy content under higher-order NGER methods.
Worked Example 1: Processing facility fuel gas
A gas processing facility combusts 12,000 GJ of raw gas in turbines and heaters over the year.
12,000 GJ × 51.53 = 618,360 kg CO₂-e
618.36 tonnes CO₂-e (Scope 1)
Worked Example 2: Wellhead line heaters
Remote wellhead heaters consume 350 GJ of unprocessed gas.
350 GJ × 51.53 = 18,035.5 kg CO₂-e
18.04 tonnes CO₂-e (Scope 1)
Worked Example 3: Field compressors metered in cubic metres
Field compressor engines meter 40,000 m³ of raw gas.
40,000 m³ × 0.0393 GJ/m³ = 1,572 GJ
1,572 GJ × 51.53 = 81,005.16 kg CO₂-e
81.01 tonnes CO₂-e (Scope 1)
How unprocessed gas compares with other gaseous fuels
| Gaseous fuel | Combined Scope 1 factor (kg CO₂-e/GJ) |
|---|---|
| Biomethane | 0.13 |
| Landfill biogas | 6.43 |
| Coke oven gas | 37.08 |
| Natural gas (pipeline) | 51.53 |
| Unprocessed natural gas | 51.53 |
| Coal seam methane | 51.63 |
| Coal mine waste gas | 56.80 |
NGER and AASB S2 Reporting
Fuel gas combustion at upstream facilities is Scope 1 under the NGER scheme and almost always sits within a registered facility’s boundary. The same combustion emissions flow into the Scope 1 inventory you disclose under AASB S2 — keep combustion, flaring and fugitive sources itemised separately so your disclosures reconcile to your NGER submission.
Related Emission Factors
Frequently Asked Questions
Disclaimer
This page is provided for general information, not professional or compliance advice. The factor shown is reproduced from the official publication cited above, and while we work to keep it current, government factors change — the publication is always the authoritative source.
- Before using this value in any formal reporting — including under the National Greenhouse and Energy Reporting Act 2007 — confirm it against the current official publication and the methods specified by the Clean Energy Regulator.
- NetNada is independent of the Australian Government, DCCEEW, and the Clean Energy Regulator. Government data is Crown copyright, Commonwealth of Australia.