The aim is to produce cars capable of traveling as much as 100 kilometers (62 miles) on four hours of charge time in the sun, the company said. Power will come from six square meters (64 square feet) of thin-film solar cells affixed to the bodies of the cars, the statement said. Hanergy Holding in August bought Alta Devices of the U.S. for technology that works for emergency charging of mobile phones and cars. A thin-film solar cell is made by placing layers of photovoltaic material on a semiconductor wafer.