*3.4. Electric Grid Parameters*

There is a need to invest in one grid connection at each charger location, irrespective of how many chargers are in the same location. It is assumed that the chargers will require so much power from the grid that one new transformer or substation will have to be built for each charger location, including some new distribution lines. The cost of a new substation will depend on the total power of all the chargers in that location. The initial cost of building a substation is set to 1 Million (M) SEK and the total cost includes an additional 1000 SEK/kW. This means that a 500-kW substation will cost SEK 1.5 M SEK and a 2 MW substation 3 MSEK. These cost levels are based on dialogue with the local electric utility company in Gothenburg, Sweden, and assume that end-stop chargers are normally not built in the city centre where cost is often much higher. When calculating the depreciation of the grid investment, the economic life for the substations and grid connection has been set to 20 years.

There is also an annual fee for using the grid. This can be very different in different regions, and in this paper, it includes one fixed annual fee per substation of 5000 SEK per year plus an annual fee depending on the installed peak power of the chargers, which is 500 SEK/kW per year.
