Probabilistic impact assessment of EV charging on residential UK LV networks

(paper accepted) The electricity demand from high penetrations of electric vehicles (EVs) in the UK may result in significant asset capacity issues (transformers and cables) and/or voltage drops in residential low voltage (LV) networks. This paper presents a probabilistic impact assessment of realistic EV charging on nine UK LV networks that are part of the ‘My Electric Avenue’ project. A deterministic impact assessment is initially compared against the stochastic to highlight the benefits of the latter. Monte Carlo simulations (considering 1-min resolution data) are undertaken to cater for domestic and EV load profile uncertainties. Results show that simplified (deterministic) analyses cannot truly quantify the impacts of EVs in LV networks. More importantly, the probabilistic assessment highlights that technical problems in these LV networks may occur for EV penetrations larger than 30%, and that 20 and 50% of the feeders and transformers, respectively, may exceed their capacity limits for high penetrations. Guidelines to adapt the probabilistic approach to help a network planner are finally discussed.