Multibandgap photovoltaic receiver using back surface reflectors

Requirements for prime power generation from solar arrays are expected to increase for the next generation of spacecraft power systems. An enhancement of the efficiency of the conversion of incident sunlight to electricity would have a number of advantages, provided the cost involved in achieving this enhancement would not be too great. Solar input response can be improved by splitting the solar spectrum into component wavelength bands and directing these bands to solar cells of different bandgaps. Two approaches have been proposed for achieving spectrum splitting photovoltaics. One approach involves multiple-cell systems using dichroic mirrors, while the other employs monolithic multibandgap solar cells. The present investigation is concerned with a procedure which has the advantages of both approaches, while avoiding many of the drawbacks of each.