A Recharging Industry Rises - NYTimes.com Sam Hodgson for The New York Times Michael D. Farkas, co-founder and chief of the CarCharging Group, which is buying up high-voltage recharging networks. WASHINGTON - Tens of thousands of new electric cars are zipping into traffic this year, and with them come a trunkful of strategies about how to recharge them. Steve Ruark for The New York Times Robert Bruninga plugging in his electric Toyota Prius at his home in Glen Burnie, Md. There are at least four ways to go: recharging slowly through a standard 120-volt wall socket, the type a consumer would use for a hair dryer; buying a faster 240-volt home charger, about the size of a garden gnome, for several thousand dollars; plugging into the same 240-volt charger in a public parking space but paying a price; or using a $30,000 superspeedy public charger that takes only minutes but is not widely available. The only consensus is that the more opportunities there are to recharge, the better the sales of vehicles that can generally go fewer than 100 miles between plug-ins. Not surprisingly, the chief executive of a company that has bought up thousands of high-voltage devices thinks they are the best way to recharge. The CarCharging Group, based in Miami, has quietly purchased four companies with networks of chargers, 13,430 in all. CarCharging has installed the high-voltage devices, some dressed up to mimic a gasoline pump, in underground parking garages, where drivers plug in and pay for the electricity through a device that resembles a credit card. But the price, 49 cents a kilowatt-hour - roughly four times what people pay for electricity in their homes - often makes the electric car more expensive per mile than the gasoline car it replaced. The high-voltage devices, though, take less than an hour to charge a car that has driven 20 miles from a person's home to their office, enabling garage valets who park the cars to move them around, charging several during the day. Such public charging has an advantage over the 240-volt charger that a car owner can install in a garage or car port, said Michael D. Farkas, the founder and chief executive of the CarCharging Group, because in a private home, the charger is typically used for just one car. "We're able to amortize it over several users," Mr. Farkas said. The smaller home chargers typically take two or more hours to recharge a car. CarCharging installs chargers like soft drink machines, retaining ownerships and revenue, and giving landlords a cut. Another company, ChargePoint, manufactures the devices (including some for CarCharging) and sells them, usually to landlords, to use as they please. A shopping mall owner, for example, could set up a machine to dispense electricity free for two hours and then bill at a high rate after that, encouraging shoppers to visit but not hog the charger. An employer might program the machine to provide free electricity but only to authorized users. Strategies differ, said Dimitrios Papadogonas, vice president of marketing for ChargePoint, but "it's not surprising that there's some confusion, because it's a new industry and it's getting sorted out." Mr. Papadogonas and Mr. Farkas agreed that public charging was needed because some potential buyers could not plug in at home. A new study by researchers at Carnegie Mellon University in Pittsburgh and the University of Glasgow found that in the United States, less than half of vehicles have a regular off-street parking spot at a place owned by the driver, where a charger could be installed. Stepping into this picture, last month eight states announced a joint effort to bolster electric cars, partly by requiring the installation of chargers in certain categories of buildings, like multifamily apartment structures. But it is a tough business. Last month CarCharging bought the Blink network's 12,450 chargers because its owner, Ecotality, had gone bankrupt despite $114.8 million from the Energy Department to help build the network. Blink had trouble keeping its chargers in good repair. In February, CarCharging bought Beam Charging, which has contracts with 400 parking garages. In April it bought EVPass, with chargers in central and upstate New York, and 350Green, with 600 installations, in the Midwest and California. But Mr. Farkas acknowledged that 49 cents a kilowatt-hour was equivalent to the cost of gasoline at current prices for a car that gets 21 miles per gallon, a substandard rate in 2013. The company is considering offering a flat monthly rate, $100 for off-peak charging and $150 for anytime charging, which, he said, mimicked the gasoline expense of a typical car. Still, the car would have to go about 600 miles a month for the driver to break even, difficult in a car that cannot make long trips.