Overview
SusDevOS calculates all GHG emissions server-side. You enter the activity quantity (kWh, litres, km, £ spend, etc.) and SusDevOS multiplies it by the correct emission factor and GWP value to produce a tCO₂e figure. You never enter a CO₂e value directly — if you do, it will be overwritten on save.
The formula is:
Emissions (kg CO₂e) = Quantity × Emission Factor × GWP₁₀₀
Creating an Emissions Record
- Navigate to Emissions → Records and click New Record.
- Set the Scope (1, 2, or 3).
- Select a Reporting Period — this links the record to an open GHG Inventory.
- Choose an Emission Factor from the library (DEFRA, EPA, or Climatiq).
- Enter the Quantity and select the Unit. SusDevOS converts to canonical units automatically before applying the factor.
- (Optional) Link the record to a Project or Land Parcel.
- Click Save. The tCO₂e figure appears immediately.
Scope 1 — Direct Emissions
Scope 1 covers emissions from sources owned or controlled by your organisation:
| Source | Unit to enter |
|---|---|
| Natural gas (boilers, furnaces) | kWh or m³ |
| Company vehicles (petrol, diesel) | litres or km |
| Refrigerant top-ups (HFCs) | kg of refrigerant |
| Biomass combustion | tonnes of fuel |
Biogenic CO₂: If your Scope 1 includes biomass combustion, the biogenic CO₂ is calculated separately in
BiogenicCO₂AmountTonnes. It does not appear in your GWP total — this is correct GHG Protocol behaviour. It is disclosed separately in your inventory report.
Scope 2 — Purchased Electricity, Heat, Steam
Scope 2 always produces two numbers: location-based and market-based. See the Scope 2 Dual Method guide for the full explanation.
To record Scope 2:
- Set Scope = 2 and select the Electricity subcategory.
- Enter kWh consumed.
- If you hold energy attribute certificates (REGOs, GOs, RECs), set the market-based emission factor to
0or select your supplier's certified tariff. - Both figures are calculated and stored automatically.
Scope 3 — Value Chain (all 15 categories)
SusDevOS supports all 15 Scope 3 categories from the GHG Protocol Corporate Value Chain Standard. Common ones:
| Category | Typical input |
|---|---|
| 1 — Purchased goods & services | £ spend or tonnes of material |
| 3 — Fuel- and energy-related | kWh or litres (upstream factor applied) |
| 4 — Upstream transportation | tonne-km or £ spend |
| 6 — Business travel | km by mode or £ spend |
| 11 — Use of sold products | kWh or units sold × in-use factor |
| 15 — Investments | £ invested × EXIOBASE factor |
For spend-based Scope 3 categories, SusDevOS converts your spend to USD using the daily ECB exchange rate before applying the EXIOBASE factor. The exchange rate used is stored on every record for audit.
Choosing an Emission Factor
Open the Emission Factors library (sidebar → Emission Factors) to browse and search. Factors are organised by:
- Source (DEFRA, EPA, Climatiq)
- Category (fuel, electricity, transport, waste, etc.)
- Unit (kWh, litres, km, £, kg, etc.)
If you can't find the right factor in the library, use the Climatiq integration to search the Climatiq database directly from Settings → Integrations.
GWP Dataset
By default, SusDevOS uses IPCC AR6 GWP100 values. You can switch to AR5 or AR4 in Settings → Calculation Settings if required by your reporting framework. Changing the dataset applies to all new calculations; existing records retain their original GWP until explicitly recalculated.