Experimental study of a hybrid solar thermoelectric generator energy conversion system

The development of renewable energy technologies to take advantage of clean energy sources, such as solar, is crucial for sustainability. Here, we show a hybrid solar thermoelectric (HSTE) concept that simultaneously recovers heat from the sun with a thermosyphon and generates electricity with a thermoelectric generator (TEG) via the Seebeck effect. In this work, we experimentally demonstrated a relatively low-temperature HSTE prototype that combines a cartridge heater (to emulate the sun), a TEG to generate electricity, and a thermosyphon. This thermosyphon consists of three zones: an evaporator, an adiabatic region, and a condenser. The TEG was located between the heater and the evaporator. The thermosyphon was used to maintain constant the lowtemperature face of the TEG and to recover heat in the condenser zone. A thermal resistance model was developed to understand the HSTE. Our model shows good agreement with the experimental data and guides the further development of the system. To evaluate the technical feasibility and performance of the HSTE, we characterized the HSTE by measuring the temperatures, condenser flow rate, voltage, and current under 72 different experimental conditions. We reported an electrical power of up to 96 mW and a recovered heat up to 68.18 W, when 118 W were supplied through the cartridge heater. Deionized water was the working fluid showing a higher electrical power generation than a 40% ethylene glycol solution.