Learn more about the algorithm we use to calculate footprints in the category energy, which data sources are used and which we plan for the future.
Calculations for energy
The calculation of energy consumption is divided into heating of homes, heating of water, electricity for light, and electricity for other appliances. We first calculate a total energy consumption for the household based on housing type, size and year of construction, then we divide into the various subcategories. Important sources here are Statistics Norway's energy consumption in households, research on energy consumption as a function of the age of the home (Sandberg et al. (2016)), and NVE's ratios for energy consumption in buildings.
Electricity mix
In Norway, the majority of energy consumption comes from electricity. In Ducky's calculation, we use average emissions from European electricity production. We use data from Eurostat on the actual monthly electricity production at various energy sources. This is combined with emission factors for each energy source, as well as a factor that describes losses between production and the consumption stage. In the current calculation, a running average for 2021 of 293 gCO2 eq / kWh is used.
Ducky is aware that this is a topic of discussion and has studied our position in a separate article which you can find here. In the long run, it will be possible for professional users to choose power mixes themselves in the user interface, so that if they want to retrieve a report for their municipality or Norway with Norwegian power mixes, they can do so. This will then still not be visible to most people, but can be used in public reporting.
Heating of a home
Energy consumption in heating varies with the type of house, the number of people living there, and when the house was built and last renovated. A terraced house built in 2012 with two people probably uses much less energy than a family of six who live in a large detached house from 1917.
Norwegians get heating from a number of different sources, including electricity, wood stoves, heat pumps and district heating from waste incineration. Each heat source is dedicated to a CO2intensity that we use to find the footprint. Heat pumps increase the efficiency of power consumption according to figures from Enova.
In connection with heating, we must also consider emissions of biogenic CO2, which is carbon produced from the combustion of materials that are part of the natural carbon cycle (ie NOT fossil fuels, such as wood). Although the combustion of trees that have absorbed carbon during their lifetime remains within that carbon cycle, it still increases the concentration of CO2 in the atmosphere, and contributes to climate change in the short term, so these emissions must also be taken into account.
Based on a Norwegian study on the efficiency of burning spruce, we calculate that the use of biogenic fuel has only 60% of the heating effect of carbon from fossil fuels, so that bioenergy will have a significantly lower climate footprint.
Water
heating is estimated based on the number of people in the household and average shower habits. 13% of the energy used in an average Norwegian household goes to heating water.
Lighting and other appliances
Electricity for lighting and other electrical appliances accounts for 5% and 15% of the total power consumption, respectively.
Data sources for energy
We use Matrikkelen and Folkeregisteret to map house size and heating source for households per basic district. For municipalities that have signed a data processor agreement, this data can be linked to information on household size, which provides increased accuracy in the calculation.
We are also now collaborating with Fjordkraft and Wattn, which will provide us with actual statistics on energy consumption, which will further increase the accuracy of the model. As a municipality, you can contribute to a better calculation by supporting us in our work to obtain this data.