Joseph Simfukwe
University of Zambia, Department of Physics, Zambia
Sylvester Hatwaambo
University of Zambia, Department of Physics, Zambia
Hansingo Kabumbwe
University of Zambia, Department of Physics, Zambia
Ladda ner artikelhttp://dx.doi.org/10.3384/ecp110572924Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden
Linköping Electronic Conference Proceedings 57:31, s. 2924-2929
Publicerad: 2011-11-03
ISBN: 978-91-7393-070-3
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
The current energy production from fossil fuels and nuclear energy has environmental drawbacks. These drawbacks include the creation of nuclear waste; and the pollution associated with fossil fuels which lead to global warming and climate change. It is apparent that an alternative and sustainable source of energy must be found. A potential solution to this problem is solar electricity. Currently; solar panels are expensive and hence un-economical for most buyers. The use of solar concentrators creates a potential for less expensive electricity because concentrators raise the amount of incident radiation over a relatively small area of the absorber. The reduction in cost is achieved by reducing the module area and the use of low-cost reflectors. However; specular reflectors cause high concentrated heating and form hot spots on the solar module cells. These hot spots are a result of uneven concentration of radiation. The overall effect is the reduced fill-factor and overall efficiency of the system. In this paper; we report an alternative solution to the problem of non-even illumination by using locally available low-cost semi-diffuse reflector with four different groove orientations scribed on it so as to scatter the radiation flux onto the module. The groove orientations were plain sheet (NG); horizontal grooves (HG); vertical grooves (VG); and the crisscross groove (CG) orientations. Our results show that the locally purchased semi-diffuse aluminium structure can be used as a booster reflector compared with the commercial high specular reflector.
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