Impact of higher power PEV charge levels on three U.S. radial system and field trial findings on ESB´s low voltage residential network

As plug-in electric vehicle (PEV) adoption ramps up, utilities need to maintain grid reliability and safety for adoptors and their residential neighborhood. Quantifying the relationship between electric system distribution equipment capabilities and expected residential PEV charging demand becomes an important utility planning function. PEVs are expected to charge at a rate of 3.3, 6.6, 7.2, 9.6, and 19.2 kW. As a result, a substantial number of PEVs charging at various households will significantly alter the typical demand patterns of residential networks. Utilities are implementing notification programs to identify PEV charging locations and reinforce neighborhood distribution systems, as needed. Despite our readiness efforts, PEV adopters may not notify their utility about new charging locations. This will delay necessary upgrades to the distribution infrastructure. In light of these developments and needs, the Electric Power Research Institute (EPRI) initiated a multiyear project with 19 utilities to understand PEV system impacts in the United States, Canada, and Europe. As part of this overall study EPRI developed detailed distribution and behavioral models to characterize the impact of these new loads, characterize PEV adoption, electricity usage (charging demand) and conducted field trials on residential electric distribution systems. This paper presents the results relevant with regards to two aspects from this overall study: 1) Impact of high power charge levels on distribution assets, and 2) Key findings from a year long PEV field trial conducted on residential low voltage (LV) network (400V) in Ireland.