Performance of a double pass photovoltaic thermal solar collector suitable for solar drying systems

The photovoltaic thermal solar collector, sometimes known as the hybrid solar collector generates both thermal and electrical energies simultaneously. A double pass photovoltaic thermal solar collector suitable for solar drying applications has been developed and tested. A steady state closed form solution to determine the outlet and mean photovoltaic panel temperature has been obtained for the differential equations of the upper and lower channels of the collector. Hence, the photovoltaic, thermal and combined photovoltaic thermal efficiencies can be obtained. An experimental setup has been developed. For given sets of operating and design conditions the theoretical and experimental outlet and mean photovoltaic panel temperatures can be obtained. Comparisons are made between the experimental and theoretical results and close agreement between these two values are obtained. (C) 1999 Elsevier Science Ltd. All rights reserved.