Focus

The Sun's radiation can be modeled as a 6,000-K blackbody radiator. Whereas photovoltaics (PV) can convert the part of the Sun's spectrum to electrical energy, over 40% of that spectrum, namely, the infrared (IR) range, is lost as heat. In solar thermoelectrics (TE), the thermal energy from the IR range is converted directly into electricity. Therefore, a solar PV–TE hybrid system would have access to the entire spectrum of the Sun.

Synopsis

With respect to solar energy conversion, PV devices utilize the UV region, whereas TE devices utilize the IR region (which is waste heat with respect to the PV devices) to generate electricity. In a solar PV–TE hybrid system, a high-efficiency solar collector would turn the sunlight (from the IR spectrum) into heat that would then be transformed by TE devices into usable electricity. In addition, the solar thermal energy could be stored in a thermal bath, or TE devices could be used to charge batteries that could then provide electricity when the Sun was not shining. Such a TE system would need to operate at around 1,000 K (~700 °C), and the materials would need to exhibit high ZT values around this temperature.