Primary Energy and CO2-eq Emission
When primary energy sources are converted to energy carriers and distributed to the demand side, energy is lost. The end customers purchase the carrier energy that is supplied to the building, i.e., the energy use of the building. Primary energy is quantified with the help of primary energy factors that are specific for fuel types, distribution and conversion processes. The factors used in this project are based on Swedish average values much owing to that the buildings are distributed among eight municipalities— all with different suppliers. Primary energy factors are in this project, for electricity, set to be 2.5 (Nordic marginal value) and 1.5 (national mix average value), district heating 0.9, whereas oil and wood pellets both set to 1.2, respectively (SOU 2008).
Emissions of CO2-eq are linked to the use of primary energy. Emissions used in this project are 400 and 85 CO2-eq (g/kWh) for marginal and average electricity production, 74 g/kWh for district heating (average Swedish mix value), and 300 and 10 g/kWh for oil and pellets, respectively (SOU 2008).