The Experts below are selected from a list of 579 Experts worldwide ranked by ideXlab platform
Rodolphe Vaillon - One of the best experts on this subject based on the ideXlab platform.
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Indium antimonide photovoltaic cells for near-field Thermophotovoltaics
Solar Energy Materials and Solar Cells, 2019Co-Authors: Dilek Cakiroglu, Jean-philippe Perez, Axel Evirgen, Christophe Lucchesi, Pierre-olivier Chapuis, Thierry Taliercio, Eric Tournié, Rodolphe VaillonAbstract:Indium antimonide photovoltaic cells are specifically designed and fabricated for use in a near-field thermophotovoltaic device demonstrator. The optimum conditions for growing the p-n junction stack of the cell by means of solid-source molecular beam epitaxy are investigated. Then processing of circular micron-sized mesa structures, including passivation of the side walls, is described. The resulting photovoltaic cells, cooled down to around 77 K in order to operate optimally, exhibit excellent performances in the dark and under far-field illumination by thermal sources in the [600-1000] °C temperature range. A short-circuit current beyond 10 µA, open-circuit voltage reaching almost 85 mV, fill factor of 0.64 and electrical power at the maximum power point larger than 0.5 W are measured for the cell with the largest mesa diameter under the highest illumination. These results demonstrate that these photovoltaic cells will be suitable for measuring a near-field enhancement of the generated electrical power.
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Thermionic-enhanced near-field Thermophotovoltaics
Nano Energy, 2019Co-Authors: A. Datas, Rodolphe VaillonAbstract:Abstract Solid-state heat-to-electrical power converters are thermodynamic engines that use fundamental particles, such as electrons or photons, as working fluids. Virtually all commercially available devices are thermoelectric generators, in which electrons flow through a solid driven by a temperature difference. Thermophotovoltaics and thermionics are highly efficient alternatives relying on the direct emission of photons and electrons. However, the low energy flux carried by the emitted particles significantly limits their generated electrical power density potential. Creating nanoscale vacuum gaps between the emitter and the receiver in thermionic and thermophotovoltaic devices enables a significant enhancement of the electron and photon energy fluxes, respectively, which in turn results in an increase of the generated electrical power density. Here we propose a thermionic-enhanced near-field thermophotovoltaic device that exploits the simultaneous emission of photons and electrons through nanoscale vacuum gaps. We present the theoretical analysis of a device in which photons and electrons travel from a hot LaB6-coated tungsten emitter to a closely spaced BaF2-coated InGaAs photovoltaic cell. Photon tunnelling and space charge removal across the nanoscale vacuum gap produce a drastic increase in flux of electrons and photons, and subsequently, of the generated electrical power density. We show that conversion efficiencies and electrical power densities of ∼ 30% and ∼ 70 W/cm2 are achievable at 2000 K for a practicable gap distance of 100 nm, and thus greatly enhance the performances of stand-alone near-field thermophotovoltaic devices (∼10% and ∼10 W/cm2). A key practical advantage of this nanoscale energy conversion device is the use of grid-less cell designs, eliminating the issue of series resistance and shadowing losses, which are unavoidable in conventional near-field thermophotovoltaic devices.
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thermionic enhanced near field Thermophotovoltaics for medium grade heat sources
Applied Physics Letters, 2019Co-Authors: A. Datas, Rodolphe VaillonAbstract:Conversion of medium-grade heat (temperature from 500 to 1000 K) into electricity is important in applications such as waste heat recovery or power generation in solar thermal and co-generation systems. At such temperatures, current solid-state devices lack either high conversion efficiency (thermoelectrics) or high-power density capacity (Thermophotovoltaics and thermionics). Near-field Thermophotovoltaics (nTPV) theoretically enables high-power density and conversion efficiency by exploiting the enhancement of thermal radiation between a hot emitter and a photovoltaic cell separated by nanometric vacuum gaps. However, significant improvements are possible only at very small gap distances (<100 nm) and when ohmic losses in the photovoltaic cell are negligible. Both requirements are very challenging for current device designs. In this work, we present a thermionic-enhanced near-field thermophotovoltaic (nTiPV) converter consisting of a thermionic emitter (graphite) and a narrow bandgap photovoltaic cell (InAs) coated with low-workfunction nanodiamond films. Thermionic emission through the vacuum gap electrically interconnects the emitter with the front side of the photovoltaic cell and generates an additional thermionic voltage. This avoids the use of metal grids at the front of the cell and virtually eliminates the ohmic losses, which are unavoidable in realistic nTPV devices. We show that nTiPV operating at 1000 K and with a realizable vacuum gap distance of 100 nm enables a 10.7-fold enhancement of electrical power (6.73 W/cm2) and a 2.8-fold enhancement of conversion efficiency (18%) in comparison with a realistic nTPV device having a series resistance of 10 mΩ·cm2.
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Micron-sized liquid nitrogen-cooled indium antimonide photovoltaic cell for near-field Thermophotovoltaics.
Optics express, 2019Co-Authors: Rodolphe Vaillon, Dilek Cakiroglu, Jean-philippe Perez, Christophe Lucchesi, Pierre-olivier Chapuis, Thierry Taliercio, Eric TourniéAbstract:Simulations of near-field thermophotovoltaic devices predict promising performance, but experimental observations remain challenging. Having the lowest bandgap among III-V semiconductors, indium antimonide (InSb) is an attractive choice for the photovoltaic cell, provided it is cooled to a low temperature, typically around 77 K. Here, by taking into account fabrication and operating constraints, radiation transfer and low-injection charge transport simulations are made to find the optimum architecture for the photovoltaic cell. Appropriate optical and electrical properties of indium antimonide are used. In particular, impact of the Moss-Burstein effects on the interband absorption coefficient of n-type degenerate layers, and of parasitic sub-bandgap absorption by the free carriers and phonons are accounted for. Micron-sized cells are required to minimize the huge issue of the lateral series resistance losses. The proposed methodology is presumably relevant for making realistic designs of near-field thermophotovoltaic devices based on low-bandgap III-V semiconductors.
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High-injection effects in near-field thermophotovoltaic devices
Scientific Reports, 2017Co-Authors: Etienne Blandre, Pierre-olivier Chapuis, Rodolphe VaillonAbstract:In near-field Thermophotovoltaics, a substantial enhancement of the electrical power output is expected as a result of the larger photogeneration of electron-hole pairs due to the tunneling of evanescent modes from the thermal radiator to the photovoltaic cell. The common low-injection approximation, which considers that the local carrier density due to photogeneration is moderate in comparison to that due to doping, needs therefore to be assessed. By solving the full drift-diffusion equations, the existence of high-injection effects is studied in the case of a GaSb p-on-n junction cell and a radiator supporting surface polaritons. Depending on doping densities and surface recombination velocity, results reveal that high-injection phenomena can already take place in the far field and become very significant in the near field. Impacts of high injection on maximum electrical power, short-circuit current, open-circuit voltage, recombination rates, and variations of the difference between quasi-Fermi levels are analyzed in detail. By showing that an optimum acceptor doping density can be estimated, this work suggests that a detailed and accurate modeling of the electrical transport is also key for the design of near-field thermophotovoltaic devices.
Ivan Celanovic - One of the best experts on this subject based on the ideXlab platform.
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practical emitters for Thermophotovoltaics a review
Journal of Photonics for Energy, 2019Co-Authors: Reyu Sakakibara, John D. Joannopoulos, Marin Soljacic, Walker R Chan, Veronika Stelmakh, Michael Ghebrebrhan, Ivan CelanovicAbstract:Thermophotovoltaic (TPV) systems are promising for harnessing solar energy, waste heat, and heat from radioisotope decay or fuel combustion. TPV systems work by heating an emitter that emits light that is converted to electricity. One of the key challenges is designing an emitter that not only preferentially emits light in certain wavelength ranges but also simultaneously satisfies other engineering constraints. To elucidate these engineering constraints, we first provide an overview of the state of the art, by classifying emitters into three categories based on whether they have been used in prototype system demonstrations, fabricated and measured, or simulated. We then present a systematic approach for assessing emitters. This consists of five metrics: optical performance, ability to scale to large areas, stability at high temperatures, ability to integrate into the system, and cost. Using these metrics, we evaluate and discuss the reported results of emitters used in system demonstrations. Although there are many emitters with good optical performance, more studies on their practical attributes are required, especially for those that are not yet used in prototype systems. This framework can serve as a guide for the development of emitters for long-lasting, high-performance TPV systems.
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towards a portable mesoscale thermophotovoltaic generator
Journal of Physics: Conference Series, 2018Co-Authors: Walker R Chan, Marin Soljacic, Veronika Stelmakh, Sunny Karnani, C M Waits, J D Joannopoulos, Ivan CelanovicAbstract:Thermophotovoltaics (TPV) is the conversion of fuel to electricity with heat and light as intermediaries, and is a promising source of high energy density power at the mesoscale. This work describes our transition from our bench-top experiments to a fully-integrated portable generator. Specifically, we redesigned the microcombustor for propane-air combustion from the previous propane-oxygen design. Next, we validated vacuum package of the microcombustor, necessary to preserve the photonic crystal, in a 50+ day experiment in which there was no degradation of vacuum level. Finally, we vacuum packaged a microcombustor with integrated photonic crystals in a housing with two infrared-transparent windows to transmit the thermal radiation to external PV cells. Although considerable challenges remain, this work demonstrates the feasibility of a mesoscale TPV system.
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toward high performance radioisotope thermophotovoltaic systems using spectral control
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2016Co-Authors: Xiawa Wang, Ivan Celanovic, Walker R Chan, Veronika Stelmakh, P H FisherAbstract:Abstract This work describes RTPV-PhC-1, an initial prototype for a radioisotope thermophotovoltaic (RTPV) system using a two-dimensional photonic crystal emitter and low bandgap thermophotovoltaic (TPV) cell to realize spectral control. We validated a system simulation using the measurements of RTPV-PhC-1 and its comparison setup RTPV-FlatTa-1 with the same configuration except a polished tantalum emitter. The emitter of RTPV-PhC-1 powered by an electric heater providing energy equivalent to one plutonia fuel pellet reached 950 °C with 52 W of thermal input power and produced 208 mW output power from 1 cm 2 TPV cell. We compared the system performance using a photonic crystal emitter to a polished flat tantalum emitter and found that spectral control with the photonic crystal was four times more efficient. Based on the simulation, with more cell areas, better TPV cells, and improved insulation design, the system powered by a fuel pellet equivalent heat source is expected to reach an efficiency of 7.8%.
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photonic crystal enabled Thermophotovoltaics for a portable microgenerator
Journal of Physics: Conference Series, 2015Co-Authors: Walker R Chan, John D. Joannopoulos, Marin Soljacic, Veronika Stelmakh, C M Waits, Ivan CelanovicAbstract:This work presents the design and characterization of a first-of-a-kind millimeter- scale thermophotovoltaic (TPV) system using a metallic microburner, photonic crystal emitter, and low-bandgap photovoltaic (PV) cells. In our TPV system, combustion heats the emitter to incandescence and the resulting thermal radiation is converted to electricity by the low bandgap PV cells. Our motivation is to harness the high specific energy of hydrocarbon fuels at the micro- and millimeter-scale in order to meet the increasing power demands of micro robotics and portable electronics. Our experimental demonstration lays the groundwork for developing a TPV microgenerator as a viable battery replacement.
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thermophotovoltaic and thermoelectric portable power generators
Proceedings of SPIE, 2014Co-Authors: Walker R Chan, John D. Joannopoulos, C M Waits, Ivan CelanovicAbstract:The quest for developing clean, quiet, and portable high energy density, and ultra-compact power sources continues. Although batteries offer a well known solution, limits on the chemistry developed to date constrain the energy density to 0.2 kWh/kg, whereas many hydrocarbon fuels have energy densities closer to 13 kWh/kg. The fundamental challenge remains: how efficiently and robustly can these widely available chemical fuels be converted into electricity in a millimeter to centimeter scale systems? Here we explore two promising technologies for high energy density power generators: Thermophotovoltaics (TPV) and thermoelectrics (TE). These heat to electricity conversion processes are appealing because they are fully static leading to quiet and robust operation, allow for multifuel operation due to the ease of generating heat, and offer high power densities. We will present some previous work done in the TPV and TE fields. In addition we will outline the common technological barriers facing both approaches, as well as outline the main differences. Performance for state of the art research generators will be compared as well as projections for future practically achievable systems. A viable TPV or TE power source for a ten watt for one week mission can be built from a <10% efficient device which is achievable with current state of the art technology such as photonic crystals or advanced TE materials.
A. Datas - One of the best experts on this subject based on the ideXlab platform.
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Thermionic-enhanced near-field Thermophotovoltaics
Nano Energy, 2019Co-Authors: A. Datas, Rodolphe VaillonAbstract:Abstract Solid-state heat-to-electrical power converters are thermodynamic engines that use fundamental particles, such as electrons or photons, as working fluids. Virtually all commercially available devices are thermoelectric generators, in which electrons flow through a solid driven by a temperature difference. Thermophotovoltaics and thermionics are highly efficient alternatives relying on the direct emission of photons and electrons. However, the low energy flux carried by the emitted particles significantly limits their generated electrical power density potential. Creating nanoscale vacuum gaps between the emitter and the receiver in thermionic and thermophotovoltaic devices enables a significant enhancement of the electron and photon energy fluxes, respectively, which in turn results in an increase of the generated electrical power density. Here we propose a thermionic-enhanced near-field thermophotovoltaic device that exploits the simultaneous emission of photons and electrons through nanoscale vacuum gaps. We present the theoretical analysis of a device in which photons and electrons travel from a hot LaB6-coated tungsten emitter to a closely spaced BaF2-coated InGaAs photovoltaic cell. Photon tunnelling and space charge removal across the nanoscale vacuum gap produce a drastic increase in flux of electrons and photons, and subsequently, of the generated electrical power density. We show that conversion efficiencies and electrical power densities of ∼ 30% and ∼ 70 W/cm2 are achievable at 2000 K for a practicable gap distance of 100 nm, and thus greatly enhance the performances of stand-alone near-field thermophotovoltaic devices (∼10% and ∼10 W/cm2). A key practical advantage of this nanoscale energy conversion device is the use of grid-less cell designs, eliminating the issue of series resistance and shadowing losses, which are unavoidable in conventional near-field thermophotovoltaic devices.
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thermionic enhanced near field Thermophotovoltaics for medium grade heat sources
Applied Physics Letters, 2019Co-Authors: A. Datas, Rodolphe VaillonAbstract:Conversion of medium-grade heat (temperature from 500 to 1000 K) into electricity is important in applications such as waste heat recovery or power generation in solar thermal and co-generation systems. At such temperatures, current solid-state devices lack either high conversion efficiency (thermoelectrics) or high-power density capacity (Thermophotovoltaics and thermionics). Near-field Thermophotovoltaics (nTPV) theoretically enables high-power density and conversion efficiency by exploiting the enhancement of thermal radiation between a hot emitter and a photovoltaic cell separated by nanometric vacuum gaps. However, significant improvements are possible only at very small gap distances (<100 nm) and when ohmic losses in the photovoltaic cell are negligible. Both requirements are very challenging for current device designs. In this work, we present a thermionic-enhanced near-field thermophotovoltaic (nTiPV) converter consisting of a thermionic emitter (graphite) and a narrow bandgap photovoltaic cell (InAs) coated with low-workfunction nanodiamond films. Thermionic emission through the vacuum gap electrically interconnects the emitter with the front side of the photovoltaic cell and generates an additional thermionic voltage. This avoids the use of metal grids at the front of the cell and virtually eliminates the ohmic losses, which are unavoidable in realistic nTPV devices. We show that nTiPV operating at 1000 K and with a realizable vacuum gap distance of 100 nm enables a 10.7-fold enhancement of electrical power (6.73 W/cm2) and a 2.8-fold enhancement of conversion efficiency (18%) in comparison with a realistic nTPV device having a series resistance of 10 mΩ·cm2.
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night time performance of a storage integrated solar thermophotovoltaic sistpv system
Solar Energy, 2014Co-Authors: Ananthanarayanan Veeraragavan, L Montgomery, A. DatasAbstract:Abstract Energy storage at low maintenance cost is one of the key challenges for generating electricity from the solar energy. This paper presents the theoretical analysis (verified by CFD) of the night time performance of a recently proposed conceptual system that integrates thermal storage (via phase change materials) and Thermophotovoltaics for power generation. These storage integrated solar thermophotovoltaic (SISTPV) systems are attractive owing to their simple design (no moving parts) and modularity compared to conventional Concentrated Solar Power (CSP) technologies. Importantly, the ability of high temperature operation of these systems allows the use of silicon (melting point of 1680 K) as the phase change material (PCM). Silicon’s very high latent heat of fusion of 1800 kJ/kg and low cost ($1.70/kg), makes it an ideal heat storage medium enabling for an extremely high storage energy density and low weight modular systems. In this paper, the night time operation of the SISTPV system optimised for steady state is analysed. The results indicate that for any given PCM length, a combination of small taper ratio and large inlet hole-to-absorber area ratio are essential to increase the operation time and the average power produced during the night time. Additionally, the overall results show that there is a trade-off between running time and the average power produced during the night time. Average night time power densities as high as 30 W/cm2 are possible if the system is designed with a small PCM length (10 cm) to operate just a few hours after sun-set, but running times longer than 72 h (3 days) are possible for larger lengths (50 cm) at the expense of a lower average power density of about 14 W/cm2. In both cases the steady state system efficiency has been predicted to be about 30%. This makes SISTPV systems to be a versatile solution that can be adapted for operation in a broad range of locations with different climate conditions, even being used off-grid and in space applications.
Edgar Meyhofer - One of the best experts on this subject based on the ideXlab platform.
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near field Thermophotovoltaics for efficient heat to electricity conversion at high power density
Nature Communications, 2021Co-Authors: Rohith Mittapally, Pramod Reddy, Byungjun Lee, Linxiao Zhu, Amin Reihani, Ju Won Lim, Dejiu Fan, Stephen R Forrest, Edgar MeyhoferAbstract:Thermophotovoltaic approaches that take advantage of near-field evanescent modes are being actively explored due to their potential for high-power density and high-efficiency energy conversion. However, progress towards functional near-field thermophotovoltaic devices has been limited by challenges in creating thermally robust planar emitters and photovoltaic cells designed for near-field thermal radiation. Here, we demonstrate record power densities of ~5 kW/m2 at an efficiency of 6.8%, where the efficiency of the system is defined as the ratio of the electrical power output of the PV cell to the radiative heat transfer from the emitter to the PV cell. This was accomplished by developing novel emitter devices that can sustain temperatures as high as 1270 K and positioning them into the near-field (<100 nm) of custom-fabricated InGaAs-based thin film photovoltaic cells. In addition to demonstrating efficient heat-to-electricity conversion at high power density, we report the performance of thermophotovoltaic devices across a range of emitter temperatures (~800 K–1270 K) and gap sizes (70 nm–7 µm). The methods and insights achieved in this work represent a critical step towards understanding the fundamental principles of harvesting thermal energy in the near-field. Near-field thermophotovoltaic holds the potential for achieving high-power density and energy conversion efficiency by utilizing evanescent modes of heat transfer, yet the performance still lags behind the far-field counterpart. Here, the authors combine thermally robust planar emitter with InGaAs PV to push the limit of near-field device further.
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nanogap near field Thermophotovoltaics
Nature Nanotechnology, 2018Co-Authors: Anthony Fiorino, Dakotah Thompson, Pramod Reddy, Rohith Mittapally, Linxiao Zhu, Edgar MeyhoferAbstract:Conversion of heat to electricity via solid-state devices is of great interest and has led to intense research of thermoelectric materials1,2. Alternative approaches for solid-state heat-to-electricity conversion include thermophotovoltaic (TPV) systems where photons from a hot emitter traverse a vacuum gap and are absorbed by a photovoltaic (PV) cell to generate electrical power. In principle, such systems may also achieve higher efficiencies and offer more versatility in use. However, the typical temperature of the hot emitter remains too low (<1,000 K) to achieve a sufficient photon flux to the PV cell, limiting practical applications. Theoretical proposals3–12 suggest that near-field (NF) effects13–18 that arise in nanoscale gaps may be leveraged to increase the photon flux to the PV cell and significantly enhance the power output. Here, we describe functional NFTPV devices consisting of a microfabricated system and a custom-built nanopositioner and demonstrate an ~40-fold enhancement in the power output at nominally 60 nm gaps relative to the far field. We systematically characterize this enhancement over a range of gap sizes and emitter temperatures, and for PV cells with two different bandgap energies. We anticipate that this technology, once optimized, will be viable for waste heat recovery applications. The power output of a thermophotovoltaic device featuring an emitter and a photovoltaic cell increases by more than an order of magnitude when the gap size between the emitter and the cell is reduced to the nanoscale.
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radiative heat conductances between dielectric and metallic parallel plates with nanoscale gaps
Nature Nanotechnology, 2016Co-Authors: Bai Song, Dakotah Thompson, Anthony Fiorino, Yashar Ganjeh, Pramod Reddy, Edgar MeyhoferAbstract:Near field-based enhancements in radiative heat conductance that exceed far-field limits by orders of magnitude are demonstrated by manipulating the gap size between plane-parallel dielectric and metallic plates with nanometre precision. Recent experiments1,2,3,4 have demonstrated that radiative heat transfer between objects separated by nanometre-scale gaps considerably exceeds the predictions of far-field radiation theories5. Exploiting this near-field enhancement is of great interest for emerging technologies such as near-field Thermophotovoltaics and nano-lithography6,7,8,9,10,11,12,13 because of the expected increases in efficiency, power conversion or resolution in these applications7,11. Past measurements, however, were performed using tip-plate or sphere-plate configurations and failed to realize the orders of magnitude increases in radiative heat currents predicted from near-field radiative heat transfer theory9,14. Here, we report 100- to 1,000-fold enhancements (at room temperature) in the radiative conductance between parallel-planar surfaces at gap sizes below 100 nm, in agreement with the predictions of near-field theories9,14. Our measurements were performed in vacuum gaps between prototypical materials (SiO2–SiO2, Au–Au, SiO2–Au and Au–Si) using two microdevices and a custom-built nanopositioning platform15, which allows precise control over a broad range of gap sizes (from <100 nm to 10 μm). Our experimental set-up will enable systematic studies of a variety of near-field-based thermal phenomena16,17,18, with important implications for thermophotovoltaic applications7,19,20, that have been predicted but have defied experimental verification.
Wilhelm Durisch - One of the best experts on this subject based on the ideXlab platform.
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Thermophotovoltaics on the move to applications
Applied Energy, 2013Co-Authors: Bernd Bitnar, Wilhelm Durisch, Reto HolznerAbstract:Abstract Thermophotovoltaics (TPV) was intensively investigated as a technology for heat/electricity co-generation in the last decade of the 20th century. However, a wide-spread commercialisation has not been achieved yet. The world-record system efficiency for a TPV system using silicon photocells of 4% at 50 W electrical output power as well as a maximum electrical output power of 164 W, however at a lower efficiency of 0.84% could be demonstrated by a prototype system operating with an Yb2O3 selective emitter. Related developments of TPV system components such as radiation emitters, filters and photocells are reviewed and theoretical system simulations are compared to experimentally achieved results regarding system efficiency and the electrical output power. Finally, novel TPV applications are suggested and the commercial potential of this technology is discussed.
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high performance selective er doped yag emitters for Thermophotovoltaics
Applied Energy, 2008Co-Authors: W J Tobler, Wilhelm DurischAbstract:Abstract Selective emitters for Thermophotovoltaics have been produced by vacuum plasma-spray coating of erbium doped garnet Er 1.5 Y 1.5 Al 5 O 12 and Er 2 O 3 on the intermetallic alloy MoSi 2 . The emitters are fully operable in an oxygen-containing atmosphere at a temperature of 1600 °C, are highly thermal-shock stable, and show good selective-emitting properties. The film thickness of the rare-earth oxide was varied between 200 and 600 μm and an optimal thickness for maximum selectivity was found. Measurements with Si and GaSb photocells have been performed in order to evaluate the optimal combination emitter – photocell for real thermophotovoltaic systems.
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plasma spray coated rare earth oxides on molybdenum disilicide high temperature stable emitters for Thermophotovoltaics
Applied Energy, 2008Co-Authors: W J Tobler, Wilhelm DurischAbstract:Abstract Selective emitters for Thermophotovoltaics consisting of intermetallic alloy MoSi 2 substrate with plasma-spray coated rare-earth oxides ytterbium oxide Yb 2 O 3 , Yb-doped garnet Yb 1.5 Y 1.5 Al 5 O 12 , and erbium oxide Er 2 O 3 have been successfully tested till 1650 °C. The emitters are fully operable in an oxygen containing atmosphere, are highly thermal shock stable, and show good selective emitting properties. Shielding the high out-of-band emittance of the MoSi 2 substrate with a 4 μm thick Pt intermediate layer has resulted in reduced radiation power and emittance of the rare-earth oxide film due to multiple reflections at the interfaces. The novel technique of vacuum plasma-spray coated rare-earth oxide films on MoSi 2 is a promising way for the production of effective and high temperature stable selective thermophotovoltaic emitters.
