Louis P. Dube, Wade A. McElroy, and Darrell W. Pepper, University Of Nevada, Las Vegas
Solar power is an increasingly attractive way to sustain aircraft aloft for extended time periods without refueling. Advances in photovoltaic and battery technologies have progressed to a point where it is possible to charge and store sufficient power in the sunlight to run the vehicle off a battery all night. But solar-powered flight is, by default, underpowered. A delicate optimization of properties — weight, surface materials, and geometry, for example — is required to minimize flight power requirements so that an aircraft can fly for days at a time.