Location-based uses the average emission factor of the grid where the site is; market-based uses the factor of the electricity you actually contracted. The GHG Protocol asks you to report both for Scope 2 electricity.
- Location-based: reflects the average mix of the local grid. It does not change if you switch supplier.
- Market-based: reflects your purchasing choices. It uses the factor of your supplier or contract, or the residual mix of the country if you have no specific instrument.
What you need to do
- In the 3. Scope 2 – Electricity tab, enter the consumption (kWh) of each electricity source.
- If you have a contractual instrument (guarantee of origin, certificate, green tariff), declare it in the Type of contractual instrument column.
- BCome calculates both methods from the same data.
Good to know
- Without any instrument, the market-based result uses the residual mix, which is usually higher than the grid average.
- Differences between both results are normal and not an error.