Novel multijunction solar cell design for low cost, high concentration systems

In the quest to reduce the levelized cost of energy, recent concentrated photovoltaics innovations have striven to increase the solar cell conversion efficiency. Another approach aims at concentrating more light on the solar cell in order to reduce its share of the energy cost. We propose new cell structures that are tailored for high conversion efficiency at solar concentration exceeding 1000 suns, with a minimum amount of heat generated. These designs are composed of multiple junctions (3, 4, and 5) of materials lattice matched to gallium arsenide (GaAs) with bandgaps at or above that of GaAs. Simulations that include thermal effects and electrical resistance effects are used to predict the performances of the proposed designs under high concentrations. A relative cost analysis shows a reduction in electricity cost when using these designs compared with the state of the art triple-junction solar cell. Further cost reduction schemes using these proposed designs are discussed.