In 2016, California had the highest concentration of plug-in vehicles relative to population with 6.65 PEVs per 1,000 people, according to figures from the US Department of Energy (DOE). Hawaii had the second highest concentration with nearly four PEVs per 1,000 people followed by Washington and Oregon with about three PEVs per 1,000 people.
Vermont and Georgia round out the top six with more than two PEVs per 1,000 people. Mississippi had the lowest concentration of PEVs, but all 50 states and the District of Columbia had at least some PEVs.
PEV registrations within a state are influenced by many factors, including state and local incentive programs, charging infrastructure, and fuel pricing.