Thermophotovoltaic system configurations and spectral control

Abstract

Thermophotovoltaic (TPV) systems can be characterized by several different parameters including system electrical conversion efficiency, photovoltaic cell electric power density, infrared (IR) emitter temperature and system costs. One way of dividing TPV systems into three categories is via high (T >1400 • C), medium (T between 1400 • C and 1100 • C) and low (T < 1100 • C) IR emitter temperature. In the high T category, silicon cells can be used with porous rare earth oxide selective emitters operating at over 1400 • C. For low T emitters, cells with band gaps below 0.6 eV are being studied. These cells are typically made with ternary and quaternary compounds using MOCVD. They are being developed for space and military applications where these cells operate at temperatures of 30 • C and below. These systems can potentially have efficiencies over 15%. Diffused junction GaSb cells can be used with IR emitters in the mid-temperature range. These cells can potentially be made at low cost in high-volume production. With emitter temperatures of 1250 • C, these cells operate with power densities of 1 W cm −2 . These cells can be operated at 60 • C for combined heat and power applications. Systems using these cells can have electrical conversion efficiencies well over 10%. Spectral control is another important parameter characterizing TPV system configurations. While various means of high efficiency spectral control for low-and mid-temperature systems have now been demonstrated with single-cell experiments, the frontier now lies in integrating cell arrays, heat sources and IR emitters with spectral control into complete systems.

One–dimensional TiO2/SiO2 photonic crystal filter for thermophotovoltaic applications

“…The concept dates back to 1960s [3]. A TPV system consists of a thermal radiator, PV cells, and selective filter.…”

“…They presented high efficiency and power throughput [12]. 1D metallic-dielectric photonic crystals (1D-MDPCs) of (Ag/SiO 2 ) were also designed [5] and studied [3]. O'Sullivan et al [4] proposed and designed a 10-layer quarter-wave periodic structure (Si/ SiO2) with thicknesses of 170 and 390 nm and suggested to reduce the first layer thickness to one half of its original thickness for better performances.…”

Energy Conversion from Thermal Energy to Spectral-Controlled Radiation for Thermophotovoltaics using Porous Quartz Glass Media

“…(12)(13)(14)(15) However, the total efficiency of actual TPV systems that employ fossil fuel combustion has been reported to be only a few percent to date. (1) Therefore, the heat-to-radiation efficiency is vital to the total efficiency, in addition to the spectral efficiency. The major constraint for the implementation of TPV systems has been shown to be the limited conversion of input thermal energy to useful radiant energy.…”

“…In the system associated with the gas tight selective emitter, optical filter and recuperator, 56% of the efficiency from input thermal energy to useful radiant energy and 16.5% of the total efficiency were expected approximately. (1,24) However, the system had a disadvantage in that the glass tube window was heated and emitted a significant amount of unusable radiant energy to the TPV cells.…”

Pore Structure and Interconnectivity of CdS Aerogels and Xerogels by Hyperpolarized Xenon NMR

“…These properties, combined with the porous architecture, make them uniquely suited for a range of potential applications, including photocatalysis and optical sensing. [12][13][14][15][16][17][18][19][20] Additionally, related chalcogels prepared from condensation of molecular anionic clusters and * To whom correspondence should be addressed. E-mail: shane.pawsey@ bruker-biospin.com (S.P.…”