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in creator/contributor: "Baldasaro, P.F."  
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Physical Basis for the Maximum Thermal Radiation Emission between Materials

Description: An analytic basis for the limit on intra-media thermal radiation transport has been obtained as a simple function of temperature and material optical properties (n,k). It is shown that optical parameters determine the maximum radiative energy transfer rate by altering media radiative state density and energy density. Quantitative analysis shows that intra-media radiative transfer rates may exceed the radiation into free space as described by the Stephan-Boltzmann equation by several orders of m… more
Date: April 24, 2003
Creator: Baldasaro, P.F. & Beausang, J.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Improved Thermophotovoltaic (TPV) Performance Using Dielectric Photon Concentrations (DPC)

Description: This report presents theoretical and experimental results, which demonstrate the feasibility of a new class of thermophotovoltaic (TPV) energy converters with greatly improved power density and efficiency. Performance improvements are based on the utilization of the enhanced photon concentrations within high refractive index materials. Analysis demonstrates that the maximum achievable photon flux for TPV applications is limited by the lowest index in the photonic cavity, and scales as the minim… more
Date: January 3, 2003
Creator: Baldasaro, P. F. & Fourspring, P. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Feasibility assessment of low temperature voltaic energy conversion

Description: An experimental and theoretical investigation of the feasibility of thermo voltaic (TV) power generation in the temperature range 800{degrees}C - 1000{degrees}C has been performed. In this concept, voltaic cells of Indium-Galium-Arsenide (InGaAs) were employed to convert thermal radiation directly into electric power. The advantage of this concept over previous thermo photo voltaic concepts (TPV) is the reduced materials issues associated with a lower heat source temperature, and applicability … more
Date: April 1, 1994
Creator: Baldasaro, P. F.; Campbell, B. C.; Depoy, D. M. & Parrington, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

InGaAsSb thermophotovoltaic diode physics evaluation

Description: The hotside operating temperatures for many projected thermophotovoltaic (TPV) conversion system applications are approximately 1,000 C, which sets an upper limit on the TPV diode bandgap of 0.6 eV from efficiency and power density considerations. This bandgap requirement has necessitated the development of new diode material systems, never previously considered for energy generation. To date, InGaAsSb quaternary diodes grown lattice-matched on GaSb substrates have achieved the highest performa… more
Date: June 1, 1998
Creator: Charache, G.W.; Baldasaro, P.F. & Danielson, L.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A thermophotovoltaic energy conversion device

Description: A thermophotovoltaic device and a method for making the thermophotovoltaic device are disclosed. The device includes an n-type semiconductor material substrate having top and bottom surfaces, a tunnel junction formed on the top surface of the substrate, a region of active layers formed on top of the tunnel junction and a back surface reflector (BSR). The tunnel junction includes a layer of heavily doped n-type semiconductor material that is formed on the top surface of the substrate and a layer… more
Date: December 31, 1996
Creator: Charache, G. W.; Baldasaro, P. F. & Egley, J. L.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
open access

TPV efficiency measurements and predictions for a closed cavity geometry

Description: A thermophotovoltaic (TPV) efficiency measurement, within a closed cavity, is an integrated test which incorporates four fundamental parameters of TPV direct energy conversion. These are: (1) the TPV devices, (2) spectral control, (3) a radiation/photon source, and (4) closed cavity geometry effects. The overall efficiency of the TPV device is controlled by the TP cell performance, the spectral control characteristics, the radiator temperature and the geometric arrangement. Controlled efficienc… more
Date: May 1, 1997
Creator: Gethers, C. K.; Ballinger, C. T.; Postlethwait, M. A.; DePoy, D. M. & Baldasaro, P. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

TPV efficiency predictions and measurements for a closed cavity geometry

Description: A thermophotovoltaic (TPV) efficiency measurement, within a closed cavity, is an integrated test which incorporates four fundamental parameters of TPV direct energy conversion. These are: (1) the TPV devices, (2) spectral control, (3) a radiation/photon source, and (4) closed cavity geometry affects. The overall efficiency of the TPV device is controlled by the TPV cell performance, the spectral control characteristics, the radiator temperature and the geometric arrangement. Controlled efficien… more
Date: May 1, 1997
Creator: Gethers, C. K.; Ballinger, C. T.; Postlethwait, M. A.; DePoy, D. M. & Baldasaro, P. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

System Performance Projections for TPV Energy Conversion

Description: TPV technology has advanced rapidly in the last five years, with diode conversion efficiency approaching >30%, and filter efficiency of {approx}80%. These achievements have enabled repeatable testing of 20% efficient small systems, demonstrating the potential of TPV energy conversion. Near term technology gains support a 25% efficient technology demonstration in the two year timeframe. However, testing of full size systems, which includes efficiency degradation mechanisms, such as: nonunifor… more
Date: June 9, 2004
Creator: Baldasaro, P. F.; Dashiell, M. W.; Oppenlander, J. E.; Vell, J. L.; Fourspring, P.; Rahner, K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Status of Thermophotovoltaic Energy Conversion Technology at Lockheed Martin Corp.

Description: In a thermophotovoltaic (TPV) energy conversion system, a heated surface radiates in the mid-infrared range onto photodiodes which are sensitive at these energies. Part of the absorbed energy is converted into electric output. Conversion efficiency is maximized by reducing the absorption of non-convertible energy with some form of spectral control. In a TPV system, many technology options exist. The development efforts have concentrated on flat-plate geometries with greybody radiators, low band… more
Date: January 31, 2003
Creator: Brown, E. J.; Baldasaro, P. F.; Burger, S. R.; Danielson, L. R.; DePoy, D. M.; Nichols, G. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance Limits of Low Bandgap Thermophotovoltaic Antimonide-Based Cells for Low Temperature Radiators

Description: This paper assesses the performance of antimonide-based thermophotovoltaic cells fabricated by different technologies. In particular, the paper compares the performance of lattice matched quaternary (GaInAsSb) cells epitaxially grown on GaSb substrates to the performance of ternary (GaInSb) and binary (GaSb) cells fabricated by Zn diffusion on bulk substrates. The focus of the paper is to delineate the key performance advantages of the highest performance-to-date of the quaternary cells to the … more
Date: August 29, 2000
Creator: Borrego, J. M.; Wang, C. A.; Dutta, P. S.; Rajagopalan, G.; Bhat, I. B.; Gutmann, R. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Current status of low-temperature radiator thermophotovoltaic devices

Description: The current performance status of low-temperature radiator (< 1,000 C) thermophotovoltaic (TPV) devices is presented. For low-temperature radiators, both power density and efficiency are equally important in designing an effective TPV system. Comparisons of 1 cm x 1 cm, 0.55 eV InGaAs and InGaAsSb voltaic devices are presented. Currently, InGaAs lattice-mismatched devices offer superior performance in comparison to InGaAsSb lattice-matched devices, due to the former`s long-term development for … more
Date: May 1, 1996
Creator: Charache, G. W.; Egley, J. L.; Danielson, L. R.; DePoy, D. M.; Baldasaro, P. F.; Campbell, B. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Status of Thermophotovoltaic Energy Conversion Technology at Lockheed Martin Corporation

Description: In a thermophotovoltaic (TPV) energy conversion system, a heated surface radiates in the mid-infrared range onto photocells which are sensitive at these energies. Part of the absorbed energy is converted into electric output. Conversion efficiency is maximized by reducing the absorption of non-convertible energy with some form of spectral control. In a TPV system, many technology options exist. Our development efforts have concentrated on flat-plate geometries with greybody radiators, front sur… more
Date: July 29, 2004
Creator: Brown, E. J.; Baldasaro, P. F.; Burger, S. R.; Danielson, L. R.; DePoy, D. M.; Dolatowski, J. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermophotovoltaic Spectral Control

Description: Spectral control is a key technology for thermophotovoltaic (TPV) direct energy conversion systems because only a fraction (typically less than 25%) of the incident thermal radiation has energy exceeding the diode bandgap energy, E{sub g}, and can thus be converted to electricity. The goal for TPV spectral control in most applications is twofold: (1) Maximize TPV efficiency by minimizing transfer of low energy, below bandgap photons from the radiator to the TPV diode. (2) Maximize TPV surface p… more
Date: June 9, 2004
Creator: DePoy, D. M.; Fourspring, P. M.; Baldasaro, P. F.; Beausang, J. F.; Brown, E. J.; Dashiel, M. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Quaternary InGaAsSb Thermophotovoltaic Diodes

Description: In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature … more
Date: March 9, 2006
Creator: Dashiell, M. W.; Beausang, J. F.; Ehsani, H.; Nichols, G. J.; Depoy, D. M.; Danielson, L. R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

Description: Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of… more
Date: June 9, 2004
Creator: Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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