Energy · Scope 1
Stationary combustion
Fuel burned in boilers, furnaces, ovens and generators. The most common Scope 1 calculation, and the one every other fuel-based calculator is built on.
On this page you'll learn
- The inputs and the formula
- Why IPCC needs to know what kind of site burned the fuel
- Which extra rows a fuel can produce
- Scope
- 1 (biogenic CO₂ outside the scopes)
- Publishers
- UK DEFRA, US EPA, IPCC 2006 Vol 2 Ch 2
- Inputs
- Fuel, quantity, unit, facility, transaction date
- Category code
stationary_combustion
The method
- 1
Resolve the factor
Through your organisation's source chain, for this fuel, at the transaction date. See Factor resolution.
- 2
Convert your quantity
Onto the unit the factor is published per: litres to GJ, kg to gallons, and so on. See Units.
- 3
Multiply
Per-gas factors take your GWP set; pre-calculated CO₂e factors don't.
- 4
Add the siblings
Upstream (if switched on) and biogenic CO₂ for fuels with biological content, each as its own row.
- Q
- quantity on the factor's basis
- EF
- published factor per gas
- OX
- oxidation factor (1.0 unless stated)
- GWP
- from your organisation's set
Worked example
- Activity
- 1,000 m³ (converted to EPA's basis)
- CO₂ = Q × EF_CO₂
- kg CO₂
- CH₄ = Q × EF_CH₄, × 28
- kg CO₂e
- N₂O = Q × EF_N₂O, × 265
- kg CO₂e
- Scope 1 row
- sum, kg CO₂e
The exact factor, unit basis and GWP set used appear on the row's provenance panel. A DEFRA factor for the same fuel would arrive as one kg CO₂e figure with no GWP applied.
IPCC: what kind of site burned it
IPCC publishes stationary combustion in four tables, one per source category. CO₂ is the same in all four, because it depends only on the fuel's carbon. CH₄ and N₂O depend on the burner:
| Fuel | Energy & manufacturing (1.A.1 / 1.A.2) | Commercial & residential (1.A.4) | Ratio |
|---|---|---|---|
| Natural gas, CH₄ kg/TJ | 1 | 5 | 5× |
| Gas/diesel oil, CH₄ kg/TJ | 3 | 10 | 3.3× |
| Wood/wood waste, CH₄ kg/TJ | 30 | 300 | 10× |
So under IPCC, each facility carries a combustion source category, and a record can override it (a standby generator at an industrial plant, say). DEFRA and EPA don't split factors this way, so the category is ignored for them.
Biomass fuels
Burning wood, biogas or biodiesel releases CO₂ that plants recently took from the air. That CO₂ is reported outside the scopes; the CH₄ and N₂O from the same combustion stay in Scope 1, because they depend on how the fuel burns, not on where its carbon came from. The IPCC 2019 Refinement confirms this split.
Things to watch
- Fuel burned to make steam you then sell is still your Scope 1. Steam you buy is purchased heat.
- A kiln's fuel is stationary combustion; the CO₂ from the limestone in it is an industrial process. A works reports both.
- Five biomass fuels need your own calorific value, because EPA publishes them per energy unit only and moisture makes a default unsound.