Electricity tariffs and temporal trading opportunities from bidirectional charging of electric vehicles

In Europe and elsewhere, climate goals have resulted in electricity systems becoming more reliant on weather dependent power resources, and alongside, decarbonization initiatives in other sectors, such as electrification of transport present new demands for electricity. With more new renewables in the power systems, intermittency increases, and flexibility, for instance from demand response, becomes more important. Electric vehicles (EVs) increase the potential for demand response. On this background, we study how power prices and tariffs for grid services influence incentives to be flexible, considering different strategies for charging and possibly discharging electric vehicles. We also study the effect of consumer support schemes following the energy price crisis in Europe in 2021–2023. As an illustration, we use data from the Norwegian power market, where most household customers pay for electricity based on hourly day-ahead prices and metered volumes, and where the majority of new cars are EVs. We find that the cost savings from using smart or bidirectional charging depend critically on electricity price levels and price volatility. Grid tariffs and price support schemes will, if not properly designed, reduce the incentives for EV owners to offer flexibility via smart charging. ¹