The annual replacement costs are estimated based on the use of end energy from non-renewable resources and current costs for the provision of energy services (electricity, heat, mobility) from renewable energies.
The final consumption of electricity and heat from fossil energy sources for the observed period can almost entirely be obtained from a publication by the Federal Ministry of Economic Affairs and Energy on the structure of final energy consumption by energy source. Since the value for the end energy consumption includes both energy from renewable and non-renewable sources, the amount needs to be corrected for the share of renewable energy sources. Data on the latter is not directly available with regard to final energy use, therefore the share of renewable energy sources as part of the total gross electricity consumption is used as estimation. The situation is similar for consumption of district heating. The mix of renewable energies can also be obtained from the data source mentioned above. Transmission losses are accounted for by using a six percent markup on final energy consumption. The calculation for electricity and heat is basically a simple process: The final energy consumption from fossil energy sources of a year – differentiated by electricity and heat – is respectively multiplied by the production cost per kWh of electricity and heat from renewable sources (new installations). The transmission losses are subsequently added as a proportional markup.
Further details on the methodology and the calculation approach for mobility can be found in “Final Report on the NWI 2.0 update”.