Plug in electric cars work better in some niches than others. Battery performance is temporarily degraded when the car spends long periods of time in cold weather. The more it is necessary to heat or air condition the vehicle, the more its range declines. Electric cars are a close rival to conventional vehicles on trips of less than their daily range of 70 miles plus per day, but are not competitive for long haul trips because of their relatively short range and long recharging time. They also have longer ranges on relatively flat terrain, rather than long runs up steep highways, but have the longest ranges at lower speeds. And, at least at first, they are most attractive in places with high population density, so that a modest investment in infrastructure can serve as many vehicles as possible.
Where is the perfect fit for the Nissan Leaf and its cousins on the drawing board? Hawaii, or more specifically, the island of O'ahu, whose 596.7 square miles (roughly 44 miles by 30 miles) are home to 876,151 people (and many more tourists) which iis about two-thirds of the total state population and gives it a population density greater than that of any entire U.S. state. The average monthly low temperature there never falls below 65 degrees (February) and the average monthly high temperature never exceeds 88 degrees (August), with local standards of dress making higher temperatures tolerable with modest or no air conditioning. Conveniently, the island of O'ahu is governed by a single consolidated city and county government for Honolulu County.
Most road travel is on the Southern half of the island, and the three mountain pass on the island, on Interstate Highway 3 and state highways 61 and 63, are not particularly high as mountain passes go. The rest of the highways rarely vary by more than 500 feet in elevation and tend to do so gradually. Much of the urban traffic is the stop and go crush in which electric vehicles excel. Top highway speed limits don't exceed 60 mph and even on the biggest highways, many segments are slower.
Another factor favoring plug in electric cars in O'ahu is high gasoline prices, because they are more fuel efficient than conventional gasoline fueled vehicles, and Honolulu has some of the highest gasoline prices in the nation (although its electricity is also expensive). Reducing tail pipe emissions and noise in the densely populated tourist areas of O'ahu is also a plus.
O'ahu's electricity is expensive mostly because it is generates almost entirely with oil. Hawaii is the only state other than Alaska where this is the case. A single modest sized nuclear power plant combined with renewable sources like windmills and tidal power plants would solve the cost and pollution problems, and is hard for a state that regularly hosts nuclear submarines and aircraft carriers to object to on principle, but that further adjustment would require a state constitutional amendment, since Hawaii's current constitution prohibits nuclear power.