Performance prediction of the concentrated hybrid power/thermal system incorporating thermoelectric generators

Abstract

• The concentrated hybrid power/thermal system is proposed. • The system achieves electrical output and gets the heated fluid. • Thermoelectric generators serve a function of thermoelectric power generation well. • Thermoelectric generators improve the thermal insulation of the system. • The effects of different parameters are discussed. The concentrated hybrid power/thermal system is proposed and discussed in this paper. This system, which includes the concentrator, the solar thermal collector, and thermoelectric generators, not only provides the heated fluid but also can generate electrical power by thermoelectric generators, thus, two energy conversions are realized: heat recovery and thermoelectric power generation. Theoretical investigations found that the variation trends of heat gain and electrical power of the system have a good correlation with solar radiation. During the all-day operation, the thermal and electrical performance of the concentrated hybrid power/thermal system using linear Fresnel lens is better than that of the compound parabolic concentrating power/thermal system with the all-day overall efficiency of the former of 75.59%, 5.12% higher than the latter. Also, the electrical power thermoelectric generators generate in the two systems with the maximum of 0.60 W and 0.54 W under the conditions of 4 concentration ratio and 15 ℃ initial water temperature, respectively. Additionally, the performance of the system from both viewpoints of energy and exergy analysis is investigated under conditions of different parameters of thermoelectric generators, concentration ratios, and fluid properties. The valuable conclusions provide a new thought for the application of TEG in solar systems.