Experimental investigation and optimization on photovoltaic-thermoelectric hybrid power source

Exposed to the sun, silicon solar cells will convert solar radiation energy into not only electric energy but also heat energy. The heat energy will induce the temperature rise of the solar cells. A kind of hybrid power source is presented in this paper. The solar cells are the heat source for thermoelectric generators (TEG) and the heat sinks used to dissipate heat are for cold-side of the TEG. The temperature difference between the hot-side and the cold-side makes the TEG produce electricity. The experimental investigation and the optimization of the photovoltaic-thermoelectric hybrid power source are presented. Experimental results demonstrate that the open circuit voltage of the TEG using pin-fin heat sinks is higher than the open circuit voltage using plate-fin heat sinks in the hybrid power source; comparing with the open circuit voltage of TEG using aluminium heat sinks is prone to fluctuate with the change of the environment condition using copper heat sinks; the open circuit voltage of TEG is the highest using the aluminium pin-fin heat sinks with 24 mm thickness. TEG can charge an ultracapacitor through a DC/DC converter. When the temperature difference between the cold-side and the hot-side is 1.4°C, the output current is 5.16 mA, the output voltage is 0.41 V, and the output power is 2.11 mW.