On the production costs of large-scale public charging

Electric vehicles are considered a strong alternative to traditional internal combustion vehicles because they produce no tailpipe emissions. However, people who are used to refuelling with fossil fuels in a matter of minutes may find current charging options limited. Public charging infrastructure for electric vehicles is expensive to build, and profitability depends heavily on how often people actually use these charging facilities.

This thesis examines the production costs of large-scale public charging and ways to reduce these costs in Finland. In this study, both battery electric cars and trucks are considered as users of the charging stations. The power profile of the charging sites was also analysed, and a battery energy storage system was used to reduce peak power demand. The main factors affecting the production cost of public chargers were the infrastructure components, construction, charger usage, and electricity costs. For usage rates, real-world data on battery electric cars was used, along with utilisation forecasts for battery electric trucks. Based on this data, three different scenarios were calculated across three types of areas in Finland. From these results, the number of potentially profitable charging stations was determined for each area and scenario.

For these charging stations, different power profiles were created according to varying numbers of car and truck visits, and different amounts of charged energy, using the same usage data as in the profitability analysis. These power profiles were a useful tool for evaluating methods to reduce peak power demand using a battery energy storage system. A linear optimisation algorithm was developed to optimise battery energy storage system usage based on a one-year power profile. The results show that using a battery energy storage system sized between 500 and 2000 kW/kWh at large public charging stations is financially profitable in most cases and it also provides reliable peak power reduction.