Energy Analyses of Thermoelectric Renewable Energy Sources

Abstract

The recent energy crisis and environmental burden are becoming increasingly urgent and drawing enormous attention to solar-energy utilization. Direct solar thermal power generation technologies, such as, thermoelectric, thermionic, magneto hydrodynamic, and alkali-metal thermoelectric methods, are among the most attractive ways to provide electric energy from solar heat. Direct solar thermal power generation has been an attractive electricity generation technology using a concentrator to gather solar radiation on a heat collector and then directly converting heat to electricity through a thermal electric conversion element. Compared with the traditional indirect solar thermal power technology utilizing a steam-turbine generator, the direct conversion technology can realize the thermal to electricity conversion without the conventional intermediate mechanical conversion process. The power system is, thus, easy to extend, stable to operate, reliable, and silent, making the method especially suitable for some small-scale distributed energy supply areas. Also, at some occasions that have high requirements on system stability, long service life, and noiselessness demand, such as military and deep-space exploration areas, direct solar thermal power generation has very attractive merit in practice. At present, the realistic conversion efficiency of direct solar thermal power technology is still not very high, mainly due to material restriction and inconvenient design. However, from the energy conversion aspect, there is no conventional intermediate mechanical conversion process in direct thermal power conversion, which therefore guarantees the enormous potential of thermal power efficiency when compared with traditional indirect solar thermal power technology [1].

Performance Evaluation of the Thermoelectric Generator

“…The Bi 2 Te 3 thermoelectric generator is the most widely used due to the acceptable price, performance and low work temperature. The Bi 2 Te 3 thermoelectric generator performance can be improved if it is combined with isomorphic compounds such as PbTe, GeTe and Sb 2 Te 3 [12,13].…”

Experimental Investigation of Passive Water Cooling in Solar Heating Thermoelectric Generator

“…Any kind of heat including waste heat from automobile exhaust, geothermal and solar energy etc. can be used to heat the hot side of TEG [5], [6], [7], [8]. TEG using solar energy as the heat source can be called solar thermoelectric generator (STEG).…”

Thermoelectric Study of La2Ti2-xNbxO7 (0 ≤ x ≤ 0.25) Ceramics

“…Due to their framework structures consisting of large voids with heavy elements, they possess low phonon group velocity and thus low k which are desirable for optimised ZT [6]. Application of these materials is limited, however, due to toxicity, scarcity, cost and limited operational temperature range [7]. According to Ioffe's theory, oxides are unsuitable for TE applications owing to their strong, mixed ionic and covalent bonds, high and lower carrier mobilities resulting in low electrical conductivity [8].…”