Thermophotovoltaic power conversion from a heat-recirculating micro-emitter

Power generation using a novel configuration of a 1-10 W micro-thermophotovoltaic (micro-TPV) device is studied experimentally. A micro-emitter as a thermal heat source is a simple cylinder with an annular-type shield that applies a heat-recirculation concept and an expanded exhaust outlet that facilitates ignition, which provides stable burning in the small confinement and uniform distribution of temperature along the wall. The micro-emitter is surrounded by a chamber with cooling fins, the inner wall of which has an installation of gallium antimonide photovoltaic cells (PVCs). The performance of the micro-TPV device is most favorable at reduced length of the cooling fins unless the temperature on the PVCs is higher than the operating limit temperature for the GaSb cells. The relative position of the micro-emitter to the PVCs also affects the performance of the micro-TPV device. These observations imply that the net amount of heat irradiation onto the PVCs is more dominant than the PVC temperature in determining the TPV performance. Under optimized operating conditions, the micro-TPV device produces 2.4 W with an overall efficiency of 2.1%, indicating that the efficiency up to the PVC surface is 21% at least if a PVC efficiency of 10% at most is assumed.