Title :
Photovoltaic efficiency enhancement through thermal up-conversion
Author :
Ekins-Daukes, N.J. ; Ballard, I. ; Calder, C.D.J. ; Barnham, K.W.J. ; Trupke, T. ; Brown, Andrew ; Roberts, Jeffrey S. ; Hill, G.
Author_Institution :
Imperial Coll., London, UK
Abstract :
A scheme is presented whereby ambient thermal energy is coupled to sub-band-gap photons through the creation and recombination of electron hole pairs, thereby increasing the short-circuit current and the efficiency of a solar cell. The necessary photon-phonon coupling is demonstrated experimentally, through the observation of anti-Stokes luminescence from QW p-i-n devices. A modest efficiency enhancement is possible for a constrained PV device, but the maximum efficiency does not exceed that of the Shockley-Queisser limit. Only when a temperature difference between the PV device and QW thermal up-convertor is established, can the system exceed the Shockley-Queisser limit.
Keywords :
electron-hole recombination; luminescence; photovoltaic effects; semiconductor quantum wells; short-circuit currents; solar cells; QW p-i-n devices; Shockley-Queisser limit; ambient thermal energy; antiStokes luminescence; electron-hole pairs; electron-hole recombination; photon-phonon coupling; photovoltaic efficiency; short-circuit current; solar cell; sub-band-gap photon; thermal up-conversion;
Conference_Titel :
Photovoltaic Energy Conversion, 2003. Proceedings of 3rd World Conference on
Conference_Location :
Osaka, Japan
Print_ISBN :
4-9901816-0-3