Performance evaluation of a new design of concentrator photovoltaic and solar thermoelectric generator hybrid system

Abstract

A new configuration of a photovoltaic module and a solar thermoelectric generator in a hybrid system integrated with a microchannel heat sink has been developed. The photovoltaic module and the solar thermoelectric generator sandwich the microchannel heat sink, as they are exposed to concentrated solar radiation. This newly developed hybrid system is compared to that with a conventional configuration in which an ordinary thermoelectric generator is attached directly to the rear surface of the concentrator photovoltaic module. To evaluate the performance of the new system in comparison to the conventional one, an all-inclusive three-dimensional thermo-fluid-thermoelectric model has been developed. This model is numerically simulated and is validated with both experimental and numerical results. The findings of this study show that the new system generates more output power and can be operated at higher concentration ratios with even lower average solar cell temperatures than the conventional system. In the new configuration, the average solar cell temperature is approximately 77 °C and the total electrical output power is approximately 3.2 kW/m2 at a solar concentration ratio of 20 suns. However, the maximum possible working concentration ratio for the conventional design is 10 suns, where the solar cell temperature approaches the highest tolerable temperature of approximately 90 °C. Moreover, the total electrical output power is approximately 1.2 kW/m2. Furthermore, it is found that at CR_PV = 20, the rate of the produced thermal energy is approximately 12 kW/m2, for the conventional design while the new design achieves 15, 22, and 30 kW/m2 for CR_STEG of 1, 10, and 20, respectively. These findings have greatly aided in identifying a new design that achieves the highest performance under concentrated solar irradiance.