NVEs disclosure calculation is based on European trade in guarantees of origin and the calculation of a European Attribute Mix (European residual mix) by the Association of Issuing Bodies (AIB). The calculation method for the disclosure is based on best practice recommendations from the European RE-DISS project.
CO2 emissions from power production depend on the energy source used for production (e.g. coal, gas or water). In AIBs calculation of a European residual mix the following CO2 emission factors per production technology have been used. These are based on life cycle assessments (LCA), which include upstream and downstream effects in the entire value chain of power production:
Coal: 1119 g/kWh
Gas: 514 g/kWh
Wind: 14 g/kWh
Nuclear: 13 g/kWh
Hydro: 7 g/kWh
If these emission factors are applied to Norwegian power production in 2015, the CO2 emission factor from power production in Norway is estimated at 17 g/kWh in 2015.
The following emission figures are calculated only for use together with the electricity disclosure and are based on AIBs residual mix and best practice calculation methods based on trade in guarantees of origin.
The estimated emissions from the electricity disclosure is CO2 509 g/kWh. This does not reflect the emissions related to Norwegian generation of electricity, but is used in connection with electricity and CO2 emissions within the schemes of disclosure and guarantees of origin. This is based on calculations by AIB and the methodology of the RE-DISS project. Radioactive waste is calculated to 1 mg RW/kWh.
According to the World Energy Outlook 2013 published by IEA (International Energy Agency), the world production mix had an estimated CO2 emission factor of 532 g/kWh in 2011, while the EU production mix in 2011 had an estimated CO2 emission factor of 345 g/kWh.
More information can be found in the official Norwegian language publication of electricity disclosure 2015.