The infra red reflecting coverglass for silicon and GaAs solar cells used in near Earth and geostationary orbits

An infra red reflecting (IRR) coating has been developed at Space Technology for use with solar cell coverglasses. The IRR coating substantially improves the thermo-optical properties of solar cell assemblies (SCAs) so allowing the array to run cooler and represents a significant advance over established UV reflective coatings. In-orbit efficiency gains of between 2 and 6% have been predicted for a variety of solar cell types and orbits. The potential benefits of this technology are greatest for nonreflective silicon solar cells but equally so for gallium arsenide. The paper gives details of the development including the results of optimisation, potential benefits in orbit (theoretical and practical) and the proposed test programme.