More than half reduction in price per watt of thermoelectric device without increasing the thermoelectric figure of merit of materials

In a power generation system, the price per watt ($/W) is an important parameter to be considered for checking the feasibility for practical implementation. In this paper, we experimentally demonstrate that $/W of a thermoelectric device can be reduced to around 60%. The conventional approach to reducing $/W in thermoelectrics is to enhance the thermoelectric figure of merit (zT) of the thermoelectric materials used, which can increase the power output (W). We propose that $/W can be reduced by lowering the material consumption ($) with a slight sacrifice in power output by changing the device architecture. A simple calculation suggests that zT∼6 is needed for such a reduction in $/W based on the conventional approach. This method can be accompanied by a search for high-zT material so that further reduction in $/W can be achieved with efficient thermoelectric materials.