Fuel Combustion Emission Factors

365 fuel combustion emission factors held in the GreenCalculus MasterBrain, drawn from 7 named sources, each listed with its publisher and licence under Sources below. Values are read live from the data layer on every page build, so nothing here is re-typed and nothing can drift from the figures the calculators use. They span 18 units of measurement — 107 of them in kg CO2e per kWh — which is why the spread below is reported per unit and never blended.

Where these factors are used

Natural Gas Combustion and Biomass and Biofuel Combustion Emissions set out how factors in this group are applied, and Scope 1 Stationary Combustion Calculator and Scope 1 Biomass & Biofuel Calculator draw on them directly. Each value below names the upstream source it came from.

What this group contains

Figures are computed per unit and never blended: a median across different units would be arithmetically valid and physically meaningless. 3 further units in this group have fewer than 3 factors and are counted above but not described.

What has changed

Change history is reconstructed from every released edition of the data layer, v2025.13 to v2026.107. A factor absent from this table has held the same value throughout. A change shown as a dash moved off zero, where a percentage has no meaning. 27 further revalued factors are not listed here.

Sources, citation & machine access

Cite the upstream publisher for the values themselves. The reference below credits this compilation and, more usefully, pins the edition you read.

Say, Jeremiah (2026). Fuel Combustion Emission Factors (MasterBrain v2026.203). GreenCalculus. https://greencalculus.com/factors/fuel-combustion-emission-factors/

Cite this factor group

Values change between editions. Quoting the MasterBrain version is what lets a reader resolve the exact number you used. See the change record above for factors in this group that have moved.

For a reference manager, in BibTeX then RIS:

@misc{greencalculus_fuels_2026,
  author       = {Say, Jeremiah},
  title        = {Fuel Combustion Emission Factors},
  year         = {2026},
  howpublished = {GreenCalculus},
  note         = {MasterBrain v2026.203},
  url          = {https://greencalculus.com/factors/fuel-combustion-emission-factors/}
}

TY  - DATA
AU  - Say, Jeremiah
TI  - Fuel Combustion Emission Factors
PY  - 2026
PB  - GreenCalculus
ET  - MasterBrain v2026.203
UR  - https://greencalculus.com/factors/fuel-combustion-emission-factors/
ER  - 

Every factor on this page is readable from the open endpoint. No key, no signup:

https://greencalculus.com/wp-json/greencalculus/v1/factors/fuels

curl -s "https://greencalculus.com/wp-json/greencalculus/v1/factors/fuels?limit=500"

import requests
rows = requests.get("https://greencalculus.com/wp-json/greencalculus/v1/factors/fuels", params={"limit": 500}).json()["factors"]
print(len(rows), "factors in fuels")

Or as a spreadsheet: 293 of the 365 rows on this page, each with its source, the edition it last changed in, and its own link:

https://greencalculus.com/wp-json/greencalculus/v1/factors-export?page=fuel-combustion-emission-factors

Download this table as CSV

The download leaves out 72 rows from IPCC_2006_GL_V2, NL_CO2EMISSIEFACTOREN_2026, whose terms do not give us the right to pass their figures on in a file. They stay on this page, each beside its source, and in the endpoint above, where every row carries licence.redistributable. The per-publisher terms are on the sources register.

Both responses carry an X-GC-Version header, so a consumer can detect a new edition without diffing the payload. The CSV filename carries the edition too, so two downloads months apart do not collide.

All factors

Last changed names the data-layer edition in which a factor last took a new value, reconstructed from every released edition since v2025.13. A dash means the value has not moved since tracking began, which is the answer to "is the figure I used last year still current?".

Common questions