SPACE PHOTOVOLTAICS

The key elements of spacecraft photovoltaic cell and array design are identified and the historical development of space photovoltaics is di scussed. Important parameters are listed for earth orbiting, near-eart h, near-sun and outer planetary missions. The earth-orbiting missions are described within the context of low earth orbit, mid-altitude eart h orbit and geosynchronous earth orbit. Requirements governed by the c hoice of mission, such as total power, insolation, temperature, radiat ion environment and stowed volume, are discussed with respect to the s olar cell parameters important to that mission (conversion efficiency, weight, tolerance to the space radiation environment, cost and availa bility). Array parameters (dollars per watt, watts per kilogram, watts per square meter) are discussed for three types of arrays (rigid, lig htweight flexible and concentrator). Progress in cell efficiencies is noted with a record GaInP/GaAs cell efficiency of 26.9%. Recent advanc es in thin-film cells (copper-indium diselenide and amorphous silicon) are discussed. Manufacturing capability and progress in multiple band gap cells is noted. Space photovoltaics can look forward to an excitin g next 10 years as the demand for a variety of satellites continues to grow. (C) 1998 John Wiley & Sons, Ltd.