| 1. |
- Beckman, William A, et al.
(författare)
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TRNSYS, the most complete solar energy system modeling and simulation software
- 1994
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Ingår i: Renewable energy. - 0960-1481 .- 1879-0682. ; 5:1-4, s. 486-488
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Tidskriftsartikel (refereegranskat)abstract
- The five computer programs TRNSYS, PRESIM, TRNSED, ONLINE, and PREBID have been put together into a program package which is the most complete solar energy system modeling and simulation software that is available today.
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| 2. |
- Broman, Lars, et al.
(författare)
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Enhancing the optical efficiency of a thermophotovoltaic generator using square cones in combination with interference filters
- 1998
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Ingår i: Second World Conference on Photovoltaic Solar Energy Conversion. - Wien, Österrike.
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Konferensbidrag (refereegranskat)abstract
- The optical efficiency is a week link in all TPV systems. Many different approaches have been studied earlier, but not much on the possibility to use interference filters. Such filters can be designed to get alsmost any desired optical performance, as long as it is allowed to use a large number of layers in the multilayer stack. In practical applications this is very often not acceptable. Nevertheless such filters can still be quite good, at least for a very narrow range of incident angles. Therefore a double-cone geometry is proposed to be used in combination with such filters. This geometry will limit the range of incident angles onto the filter, which will then act more efficiently. The influence of the geometry is evaluated by means of model experiments, and a computer program has been constructed to be able to simulate this type of geometry using ray-tracing technique.
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| 3. |
- Broman, Lars, et al.
(författare)
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Optical properties of the Czechoslovakian Fresnel lens measured using a laser beam
- 1989
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Ingår i: ISES Solar World Congress. - Kobe, Japan.
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Konferensbidrag (refereegranskat)abstract
- Linear glass Fresnel lenses have been experimentally investigated by means of a narrow He-Ne laser beam, both at normal incidence and at various combinations of meridional and sagittal angles of incidence. Both rays incident on the flat and on the grooved side were studied. Results were compared with previous ray tracing results by Franc et al. The experiments suggest, contrary to ray tracing, that the grooves should face the sun in other than sun-tracking applications.
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| 4. |
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| 5. |
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| 6. |
- Broman, Lars, et al.
(författare)
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Square cones for TPV: experiments and computer simulations
- 1998
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Ingår i: Fourth NREL Conference on Thermophotovoltaic Generation of Electricity. - Denver, CO, USA.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The efficiency of a TPV generator is very dependent on selective optical properties of the chain emitter-filter-TPV cell-reflective backing. If a selective reflective edge filter using multiple reflections in dielectric layers is employed, the slope of the edge depends on the incidence angle interval. A special geometry, consisting of a double square cone between the (square) emitter and the (square) cell array, which narrows this angle interval significantly, has been constructed and investigated experimentally as well as with ray tracing analysis.
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| 7. |
- Broman, Lars, et al.
(författare)
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Use of nonimaging concentrators for moderate concentration of sunlight onto PV cells
- 1989
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Ingår i: 9thy European Photovoltaics Solar Energy Conference. - Freiburg, Tyskland.
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Konferensbidrag (refereegranskat)abstract
- The square cornet type nonimaging concentrator has been shown useful for moderate concentration of sunlight onto photovoltaic solar cells, since it creates no hot spots at the exit aperture. In this paper are presented the mathematical formulas on which the cornet designs are based, results from computer simulations on overall cornet performance compared with measurements as well as exit aperture intensity variations, measured optical concentration ratios under controlled circumstances, and cell temperature measurements under realistic circumstances. In an Appendix are given performance curves for a large number of cornets as determined from computer simulations, covering the useful range of concentration factors and acceptance angles.
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| 8. |
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| 9. |
- Lindberg, Eva, et al.
(författare)
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An animation tool for demonstrating the importance of edge filters in thermophotovoltaic applications
- 2002
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Ingår i: Renewable energy. - : Elsevier Science Ltd. - 0960-1481 .- 1879-0682. ; 28, s. 1305-1315
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Tidskriftsartikel (refereegranskat)abstract
- In order to achieve high efficiency in a thermophotovoltaic (TPV) generator, it is important that a high fraction of emitted photons with energies below the TPV cell bandgap are reflected back to the emitter. This can be accomplished in several ways, and one suggestion is to place an edge filter between the emitter and the TPV cell array in an elliptical optic design. An animation tool, developed in the Excel® program, for determining the efficiency of an optical system is presented. The animation components are a black body emitter, an edge filter, and an array of TPV cells. The tool has been used to demonstrate the importance of an efficient filter and the usefulness of optics that makes the edge of the filter as sharp as possible.
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| 10. |
- Lindberg, Eva, et al.
(författare)
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An animation tool for demonstrating the importance of edge filters in thermophotovoltaic applications
- 2003
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Ingår i: Renewable energy. - 0960-1481 .- 1879-0682. ; 28, s. 1305-1315
-
Tidskriftsartikel (refereegranskat)abstract
- In order to achieve high efficiency in a thermophotovoltaic (TPV) generator, it is important that a high fraction of emitted photons with energies below the TPV cell band gap are reflected back to the emitter. This can be accomplished in several ways, and one suggestion is to place an edge filter between the emitter and the TPV cell array in an elliptical optic design. An animation tool, developed in the Excel program, for determining the efficiency of an optical system is presented. The animation components are a black body emitter, an edge filter, and an array of TPV cells. The tool has been used to demonstrate the importance of an efficient filter and the usefulness of optics that makes the edge of the filter as sharp as possible. It is available at www.du.se/tpv.
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