9-13 July 2012
Africa/Johannesburg timezone
Home > Timetable > Session details > Contribution details
PDF | XML | iCal

Construction and evalauation of a PV/T collector under low concentration using the batch method

Presented by Mr. Gilbert SAMUKONGA on 12 Jul 2012 from 12:00 to 12:20
Type: Oral Presentation
Track: Track F - Applied Physics


Photovoltaic cells are generally made from doped semiconductors whose conductivity decrease with increase in temperature. It is anticipated that by suppressing the rise in temperature for cells under concentration by using hot water could improve the overall efficiency of the photovoltaic system. Concentrator photovoltaic/thermal (PV/T) hybrid collectors could reduce the cost of solar cells by reducing the solar cell area and employ cheap booster reflectors. The advantage of the water batch method is that transfer fluid in PV/T can easily reach practical values of 50°C and above. The thermal energy extracted by the cooling fluid (water) can be used for other purposes. The maximum achieved power output from the PV/T was 23W compared to the rated value of 18W. The thermal efficiency reached a maximum of 71.80% while electrical efficiency increased to a maximum value of 23% from a standard reference value of 14% for mono-crystalline solar cells. We observed that thermal and electrical efficiency decreased exponentially with increase in outlet temperature beyond 42°C. Therefore, the stagnant temperature of the prototype was 420°C. We also observed that the wind profile is important when designing a PV/T system because high wind profiles favour electrical efficiency than thermal output due to high thermal losses through convection and radiation at high wind speeds.






Dr. S. Hatwaambo, University of Zambia Email: shatwaambo@unza.zm



Primary authors