Solar energy conversion with fluorescent collectors
- 1k Downloads
A new principle for solar energy conversion is proposed and evaluated theoretically. Collection and concentration of direct and diffuse radiation is possible by the use of a stack of transparent sheets of material doped with fluorescent dyes. High efficiency of light collection can be achieved by light guiding and special design of collectors. The optical path length in a triangular collector is computed.
In combination with solar cells this type of collector offers the advantage of separating the various fractions of light and converting them with solar cells with different bandgaps. Theoretical conversion efficiency under optimum conditions is 32% for a system with four semiconductors.
Thermal energy conversion offers several advantages over conventional collectors: High temperature and efficiency even under weak illumination, separation of heat transport and radiation collection, low thermal mass. Thermal efficiency is computed to be between 42% and 60%. Very attractive appear hybrid systems for generation of thermal and electric energy. An estimate of the economics of electricity generation shows that due to the concentration costs can be much lower than possible today. With the use of only silicon cells the breakeven point of $0.5/W is almost reached.
Practical difficulties to be solved are: Synthesis of dyes with stringent requirements, identification of plastic materials with high transparency and development of solar cells with higher bandgaps.
PACS Codes84.60 85.60
Unable to display preview. Download preview PDF.
- 2.A.Goetzberger, W.Greubel: German Patent Application P 2620115.0-33 (1976)Google Scholar
- 3.W.Greubel, G.Baur: Appl. Phys. Lett. (to be published)Google Scholar
- 4.J.B.Birks:The Theory and Practice of Scintillation Counting. (Pergamon Press, London 1964)Google Scholar
- 5.W.A.Shureliff, R.C.Jones: J. Opt. Soc. Am.39, 912 (1949)Google Scholar
- 9.I.B.Berlman:Handbook of Fluorescence Spectra of Aromatic Molecules. 2nd Ed. (Academic Press, New York, 1971)Google Scholar
- 11.For a recent review of solar cell physics see: H.J.Hovel:Semiconductors and Semimetals, Vol. 2,Solar Cells (Academic Press, New York 1975)Google Scholar
- 12.E.D.Jackson: Trans. Conf. on the Use of Solar Energy, Tucson, (1955) (Univ. Arizona Press,5, 122 (1958)Google Scholar
- 14.Vieweg/Esser:Polymethacrylate (Hanser Verlag, München 1975)Google Scholar
- 15.Landolt-Börnstein: Vol. 3:Luminescence of Organic Substances (Springer Berlin-Heidelberg-New York 1967) p. 285Google Scholar
- 16.H.Kallmann, M.Furst: Nucleonics8, 32 (1951)Google Scholar
- 18.A.Lindmeyer, J.F.Allison: Comsat. Tech. Review3, 1 (1973)Google Scholar
- 22.J.G.Fossum, D.G.Schueler: IEDM Tech. Digest, 453 (1976)Google Scholar
- 23.J.H.H.Heinbockel, A.S.Roberts: Proc. Int. Symp. Solar Energy, Electrochem. Soc. (1976), p. 170Google Scholar