Developments in thin-film photovoltaics for space

Thin-film solar cells are important for space because of their low cost, high power density, and radiation resistance. However, significant technological hurdles remain before thin-film technology may be implemented as the primary power source for spacecraft. A large-area fabrication process for high-efficiency (> 10% AM0) cells on a lightweight substrate must still be demonstrated, and there are many issues associated with space qualification of both the photovoltaic material itself and the substrate which must be resolved. Also, new deployment, interconnection and control schemes must be developed. Ongoing efforts led and supported by the Air Force to overcome these obstacles are discussed.