Abstract

Multiple low bandgap Ga1-x Inx Sb photovoltaic cell strings are mounted around the perimeter of a cylinder parallel to a central cylindrical emitter, or radiator. These cell strings face radially inward to receive infrared (IR) radiation from the emitter, and efficiently convert this radiation into DC electric power. Reflecting surfaces are positioned on either side of each cell string to concentrate most of the IR radiation on the photovoltaic cells and return much of the balance to the emitter. The inside of the emitter is heated by flames from small gas jets from a central burner tube with a jet pattern somewhat similar to that of a gas kitchen stove. A uniform temperature along the length of the emitter is maintained by employing a gas jet hole pattern that produces a staged addition of fuel in a special burner design. Regenerative air heating is employed to increase the flame temperature and avoid large energy losses in the stack gas. Both measures increase the efficiency and reduce the size and cost of the system. The resultant unit is a compact, quiet, light weight, DC electric power source.

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