Electric vehicles in the grid – intermittent storage balancing intermittent generation

During 2018 several countries flagged their intention to phase out internal combustion engine vehicles over the coming decades. This is expected to accelerate the electrification of transport and uptake of electric vehicles, increasing the demand for electricity by approximately 30%. During this period the proportion of distributed and renewable generation sources is also expected to increase to meet CO2 emission targets. It is well known that storage can compensate for the intermittent nature of renewable energy generation, and that the storage available in electric vehicles is substantially larger than that available in current fixed domestic installations. However, the battery storage in electric vehicles must also be regarded as intermittent, i.e. only available when the vehicle is parked, and then with availability as a sink (G2V) or a source (V2G) of energy constrained by travel patterns and plans. In this paper recent work investigating the use of electric vehicles to support renewable energy generation will be reported, together with an overview V2G trials being conducted in Denmark in which the author participated mid-2018.