Abstract :
The possibility of using of thermoelectric generators in solar hybrid systems has been investigated. Four systems were examined, one
working without radiation concentration, of the traditional PV/Thermal geometry, but with TEGs between the solar cells and heat extractor,
and three other using concentrators, namely: concentrator – TEG heat extractor, concentrator PV cell TEG heat extractor,
and PV cell – concentrator – TEG – heat extractor. The TEGs based on traditional semiconductor material Bi2Te3 and designed for temperature
interval of 50–200 C were studied experimentally. It was found that the TEG’s efficiency has almost linear dependence on the
temperature difference DT between its plates, reaching 4% at DT = 155 C (hot plate at 200 C) with 3 W of power generated over the
matched load. The temperature dependencies of current and voltage are also linear; accordingly, the power generated has quadratic temperature
dependence. The experimental parameters, as well as parameters of two advanced TEGs taken from the literature, were used for
estimation of performance of the hybrid systems. The conclusions are drawn in relation to the efficiency at different modes of operation
and the cost of hybrid systems, as well as some recommendations in relation to optimal solar cells for applications in these systems.
2011 Elsevier Ltd. All rights reserved.
