Why Two Methods?
The GHG Protocol Scope 2 Guidance (2015) requires organisations to calculate and disclose both methods separately. You may not choose one and omit the other.
| Method | What it measures | Emission factor used |
|---|---|---|
| Location-based | Average emissions intensity of the regional/national electricity grid | Grid average EF (e.g. UK national grid: ~0.207 kg CO₂e/kWh) |
| Market-based | Emissions from your contracted electricity supply | Supplier-specific EF or energy attribute certificate (EAC) factor |
The market-based figure reflects voluntary renewable electricity purchases (REGOs, GOs, RECs). If you hold certificates for 100% renewable supply, your market-based Scope 2 can be zero.
How SusDevOS Calculates Both
Every time you save a Scope 2 emissions record, SusDevOS stores two separate values:
EmissionsAmountLocationBased— calculated using the grid average factor for your entity's countryEmissionsAmountMarketBased— calculated using the supplier or EAC factor you supply
Neither value overwrites the other. Both are displayed in the record and included in inventory reports.
Setting Up Your Entity's Grid Factor
SusDevOS uses national grid emission factors (from DEFRA for UK entities, EPA eGRID for US, and Climatiq for others). The factor is applied automatically based on your entity's country setting.
To change or override the grid factor: Settings → Entity → Electricity Grid Factor.
Recording a Scope 2 Entry
- Go to Emissions → Records → New Record.
- Set Scope = 2.
- Enter the kWh consumed.
- For the market-based factor:
- If you hold REGOs/GOs/RECs for this supply: select the zero-carbon tariff or enter
0. - If you have a supplier-specific declaration: enter the declared factor in kg CO₂e/kWh.
- If you have no contractual instrument: SusDevOS uses the residual mix factor (same as location-based, or your country's published residual mix).
- If you hold REGOs/GOs/RECs for this supply: select the zero-carbon tariff or enter
- Save. Both figures are calculated instantly.
In Reports
Your GHG Protocol PDF report and CSV export include both figures with clear labelling. Most voluntary reporting frameworks ask for market-based as the "primary" Scope 2 total, with location-based disclosed in a supplementary table.