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Up Conversion for Photovoltaics

Published online by Cambridge University Press:  01 February 2011

Gavin Conibeer
Affiliation:
g.conibeer@unsw.edu.au, University of New South Wales, ARC Photovoltaics Centre of Excellence, UNSW, Sydney, Sydney, 2052, Australia, +61 2 9385 7858
Avi Shalav
Affiliation:
avi.shalav@anu.edu.au, Australian National University, The Research School of Physical Sciences and Engineering, Building 60, Canberra, 0200, Australia
Thorsten Trupke
Affiliation:
trupke@btimaging.com, University of New South Wales, ARC Photovoltaics Centre of Excellence, UNSW, Sydney, NSW 2052, Sydney, 2052, Australia
Martin Green
Affiliation:
m.green@unsw.edu.au, University of New South Wales, ARC Photovoltaics Centre of Excellence, UNSW, Sydney, NSW 2052, Sydney, 2052, Australia
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Abstract

An up-converter (UC) absorbs two or more low-energy photons and emits a single high-energy photon. A down-converter (DC) absorbs a single high-energy photon and emits two or more low energy photons. The current work extends previous limiting efficiency analysis to a combination of UC and DC; an up converter with two levels; and to compare analyses using real air mass data with that modelling the sun as a blackbody. Analysis has been carried out both with the band gap of the cell as an optimized parameter and at a fixed value of 1.1eV. All of UC, DC and two level UC are shown to improve efficiencies for both spectra. Combined UC/DC improves the efficiency further for the 1.1eV band gap but gives a lower efficiency for the optimised band gap. The explanation for this unexpected result is presented based on the small coupling losses that result from absorption/re-emission in the DC. The limiting efficiencies of such an approach are very similar to several other third generation concepts such as impurity PV, Intermediate Band solar cells or three level tandems. However in practice the UC (or DC) approach has the advantage that the optical properties of the UC are decoupled from the electrical properties of the PV cell, and hence each can be optimised independently. This means that it may be the simplest third generation approach to implement using existing PV cells, if a reasonable UC efficiency can be obtained. Nonetheless experimental work on realising UC is at an early stage. Some of the work on rare earth doped UC is reviewed together with the potential to improve the spectral sensitivity to below band gap radiation.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

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References

1 Trupke, T. Green, M. A. and Würfel, P., J. Appl. Phys. 92 (2002) 4117.10.1063/1.1505677Google Scholar
2 Trupke, T. Green, M. A. and Würfel, P., J. Appl. Phys. 92 (2002) 1668.Google Scholar
3 Bird, R.E. & Riordan, C. Journal of climate and applied meteorology, 25 (1986) 87.Google Scholar
4 Trupke, T. Shalav, A. Richards, B.S. Würfel, P., Green, M.A. Solar Energy Materials & Solar Cells, 90 (2006) 3327.Google Scholar
5 Wörfel, P., “The Physics of Solar cells”, (2005, Wiley).Google Scholar
6 Shockley, W. and Queisser, H. J. J. Appl. Phys. 32, (1961) 510.Google Scholar
7 Brown, A. PhD Thesis: “Ultimate Efficiency Limits of Multiple Energy Threshold Photovoltaic Devices”, University of New South Wales, Sydney, Australia (2003).Google Scholar
8 Wörfel, P., J. of Phys. C, 15 (1982) 3967.Google Scholar
9 Conibeer, G.J. Brown, A.S. Corkish, R., Green, M.A. Proc. 19th European Photovoltaic Solar Energy Conference (Paris, June 2004) 274.Google Scholar
10 Ŝvrèek, V., Slaoui, A. and Muller, J.-C.. Thin Solid Films, 451-452 (2004) 384.Google Scholar
11 Díaz, B. González-, Guerrero-Lemus, R., Haro-González, P., Borchert, D. Hernández-Rodríguez, C., Thin Solid Films 511. 512 (2006) 473.Google Scholar
12 Vergeer, P. Vlugt, T. et al., Physical Review B, 71 (2005) 014119–11.Google Scholar
13 Shalav, A. “Rare Earth doped up-converting phosphors for an enhanced Silicon solar cell response”, PhD Thesis, UNSW (Feb 2006).Google Scholar
14 Shalav, A. Richards, B. Krämer, K., Conibeer, G. and Green, M. 4th World Conference on PEC (Hawaii, May 2006) 45.Google Scholar
15 Dieke, G. (Interscience, New York, 1968).Google Scholar
16 Keevers, M. Saris, F. Zhang, G. Zhao, J. Green, M. 26th IEEE PVSC (California, 1997) 215.Google Scholar
17 Strumpel, C. McCannl, M. J., Beaucarne, G. Slaoui, A. Canizo, C. del, Tobias, I. Proc. 20th European Photovoltaic Solar Energy Conference (Barcelona, June 2005) 87.Google Scholar
18 Ball, D. Shalav, A. and Conibeer, G. Proc. 44th ANZSES conference (Canberra, 2006).Google Scholar
19 Green, M. A.Third Generation Photovoltaics”, Springer-Verlag (2003).Google Scholar