Performance analysis of solar thermophotovoltaic conversion enhanced by selective metamaterial absorbers and emitters

Abstract

By converting broadband sunlight into narrowband thermal radiation matched to the bandgap of thermophotovoltaic (TPV) cells, solar thermophotovoltaic (STPV) systems could potentially reach a high conversion efficiency far exceeding the Shockley-Queisser limit. However, actual STPV systems exhibit much lower efficiency due to non-idealities in solar absorbers, thermal emitters and TPV cells. In this work, the STPV system with selective metamaterial solar absorber and emitter is investigated, whose conversion efficiency is between 8% and 10% with concentration factor varying between 20 and 200. This conversion efficiency is remarkably enhanced compared with the conversion efficiency of less than 2.5% for the STPV system employing black absorbers and emitters. The sidewall emission losses from the absorberemitter module and the non-unity view factor between the thermal emitter and TPV cell will diminish the performance of the STPV system, which are also quantitatively discussed in this work. Furthermore, the non-planar STPV systems with larger emitter-absorber area ratios are investigated, whose conversion efficiency can reach up to 12.6% under 200 suns when the emitter is four times as large as the absorber.

Optimizing effectiveness and robustness for solar heat absorbers composed of a periodically nano-structured surface

“…Wu et al [35] presented a solar heat collection system using a nanoimprint-patterned film of plasmonic structures, which were composed of tungsten rectangular pillars on an aluminum nitride substrate. Wang et al [34] developed black absorbers using tungsten rectangular nano-structures on a silicon dioxide film and tungsten substrate. In the same year, Hu et al [14] developed a metamaterial absorber consisting of a chromium circular-shaped ring resonator embedded in a dielectric layer and a chromium ground plane.…”

Parametric study on the thermoelectric conversion performance of a concentrated solar-driven thermionic-thermoelectric hybrid generator

“…However, the static power such as thermionic converter or generator (TIC or TIG), thermoelectric converter or generator (TEC or TEG), alkali metal thermal to electric converter (AMTEC), and thermophotovoltaic converter has aroused people's concern . Therefore, many concepts of solar‐driven static converters have been reported . Recently, Liu et al demonstrated a novel integration of carbon counter electrodes–based perovskite solar cells and TEGs, which exhibits excellent photoelectric conversion efficiency after integration.…”

“…Although the solar‐driven static power generators have been reported by some literatures, little effort has been devoted to solar‐driven static power hybrid generator . Besides, for a solar‐driven static power generator, the energy supply is from the Sun, so the role of concentrated solar radiation that has never been discussed is worth studying.…”

An Ultrawideband Metamaterial Absorber and a Parameter Retrieval Method

“…Considering a dielectric material, an applied electric field E implies in a displacement of electron cloud, creating electric dipole moments and polarizing the material. The influence of this effect is incorporated into the electric flux density vector D, which can be expressed, considering the Equation 2-17, as D = εE = ε 0 (1 + χ) E = ε 0 E + P, (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) where P = ε 0 χE is the electric polarization and is considered the material response due to an applied electric field, while the term ε 0 E is the free-space response.…”

“…Over the past few decades, services using electromagnetic wave-based systems has been increasing exponentially, and absorbers are not anymore only an exclusively military issue, but civilian as well. Nowadays, absorbers are essential to a variety of applications, such as microbolometers [2], energy harvesting [3], thermal emitters [4], [5], solar cells [6], radar cross-section reduction [7], as well as the attenuation of surface waves [8]. Along with the wide applicability of the absorbers, some demanding features have been emerging over the last few years, such as compactness, broadband, polarization-independent response, and wide-angle stability.…”