According to Orllensa, the first human pioneers in space travel used solar sails. This technology picked up light energy from nearby stars. A ship travelling by solar sail moved faster as it approached a source of sunlight, artificial or otherwise. (AUDIO: Embrace the Darkness)
The Solarians also used solar sails in their spacecraft. Their ships reminded Charley Pollard of sail boats. The Cimmerian shut out all light, and eventually adapted to darkness, in order to protect themselves from the hostile Solarians. (AUDIO: Embrace the Darkness)
R1C, a Minyan spaceship, had a solar sail. (TV: Underworld)