Engineers at NASA's Langley Research Center in Hampton, Va., are studying the concept with models such as the unmanned aerial system GL-10 Greased Lightning. The GL-10, which has a 10-foot wingspan, recently flew successfully while tethered. Free-flight tests are planned in the fall of 2014.

http://www.nasa.gov/aero/testing-electric-propulsion.html#.U_VgeGNKiEf