EV Flexibility Supply via Participation in Balancing Services: Possible Profitability for Italian End Users

Thanks to their fast and highly controllable power response, Battery Energy Storage Systems (BESS), including those in Electric Vehicles (EVs), could usefully contribute to ancillary service supply, thus enhancing power system flexibility. In this work, the supply, by EVs, of balancing services on the Italian Balancing Market (BM) is simulated, to inquire the related possible profitability for the EV owners. More precisely, for a domestic and a non-domestic end user, with different recharge needs, the EV electricity bill related to supplying the service - in a one-directional (V1G) or bi-directional (V2G) way - while recharging is evaluated, in comparison to carrying out standard (“benchmark”) recharge where energy is assumed to be bought at day-ahead market prices. A sensitivity analysis of the results is carried out, by adopting different (although constant) prices to bid for the service. With the V2G recharge, the increased energy exchanges, with respect to the V1G and to the benchmark recharge, can yield increased bills due to the charges and taxes on such exchanges. However, both for the V1G and for the V2G recharge, price regions are found for which the service can be deemed to be profitable, i.e. with the bill lower than or equal to the benchmark bill. The profitability price regions are widened, and the maximum saving with respect to the benchmark bill is increased, if partial reliefs from charges in the bill and/or an additional remuneration for capacity availability are introduced.