High-Temperature High-Efficiency Solar Thermoelectric Generators

Inspired by recent high-efficiency thermoelectric modules, we consider thermoelectrics for terrestrial applications in concentrated solar thermoelectric generators (STEGs). The STEG is modeled as two subsystems: a TEG, and a solar absorber that efficiently captures the concentrated sunlight and limits radiative losses from the system. The TEG subsystem is modeled using thermoelectric compatibility theory; this model does not constrain the material properties to be constant with temperature. Considering a three-stage TEG based on current record modules, this model suggests that 18% efficiency could be experimentally expected with a temperature gradient of 1000°C to 100°C. Achieving 15% overall STEG efficiency thus requires an absorber efficiency above 85%, and we consider two methods to achieve this: solar-selective absorbers and thermally insulating cavities. When the TEG and absorber subsystem models are combined, we expect that the STEG modeled here could achieve 15% efficiency with optical concentration between 250 and 300 suns.

[1]  H. Goldsmid,et al.  Introduction to Thermoelectricity , 2016 .

[2]  Alan W. Weimer,et al.  Evaluation of finite volume solutions for radiative heat transfer in a closed cavity solar receiver for high temperature solar thermal processes , 2013 .

[3]  A. A. Mullin,et al.  Thermoelectricity: Science and Engineering , 1962 .

[4]  Gang Chen,et al.  High-performance flat-panel solar thermoelectric generators with high thermal concentration. , 2011, Nature materials.

[5]  Robert Palumbo,et al.  Reflections on the design of solar thermal chemical reactors: thoughts in transformation , 2004 .

[6]  G. J. Snyder,et al.  Complex thermoelectric materials. , 2008, Nature materials.

[7]  Franz Faupel,et al.  Design of a Perfect Black Absorber at Visible Frequencies Using Plasmonic Metamaterials , 2011, Advanced materials.

[8]  G. J. Snyder,et al.  Thermoelectric efficiency and compatibility. , 2003, Physical review letters.

[9]  Mukul Agrawal,et al.  Design of wide-angle solar-selective absorbers using aperiodic metal-dielectric stacks. , 2009, Optics express.

[10]  Hitoshi Naito,et al.  Development of a solar receiver for a high-efficiency thermionic/thermoelectric conversion system , 1996 .

[11]  G. J. Snyder,et al.  Thermoelectric Power Generation: Efficiency and Compatibility , 2005 .

[12]  Anke Weidenkaff,et al.  A solar cavity-receiver packed with an array of thermoelectric converter modules , 2011 .

[13]  Lauryn L. Baranowski,et al.  Concentrated solar thermoelectric generators , 2012 .

[14]  Aldo Steinfeld,et al.  Optimum aperture size and operating temperature of a solar cavity-receiver , 1993 .

[15]  Ruey-Lin Chern,et al.  Polarization-independent broad-band nearly perfect absorbers in the visible regime. , 2011, Optics express.

[16]  Kazuhiro Hane,et al.  Solar selective absorbers based on two-dimensional W surface gratings with submicron periods for high-temperature photothermal conversion , 2003 .