DESIGN OF A CONCENTRATED PHOTOVOLTAIC SYSTEM FOR APPLICATION IN HIGH TUNNELS

A literature survey shows that concentrated photovoltaic systems may offer many advantages with respect to energy production in protected cultivation. This desk study examines the feasibility of incorporating an infrared reflective film which has a parabolic shape and acts as a focusing unit into the structure of a high tunnel, to allow capture of solar energy. It is anticipated that such a film can reduce the heat load on the crop by reducing IR transmission into the tunnel, and at the same time use the reflected IR radiation to produce electricity and thermal energy. The electricity is produced by an array of water cooled PV cells that are continuously positioned in the focal line of the reflective film. The cooling of the cells is done to increase their efficiency. The heat removed from the PV cells is either directly used for crop heating or stored for subsequent use. A computer code has been developed to simulate solar ray tracking and to determine the most efficient positioning of the PV array in the proposed new tunnel design. CFD simulations were done to determine the flow patterns over the high tunnel, the pressure distribution on the tunnel’s cover, the heat transfer between the PV cells and the surrounding air and cooling water and the temperature distribution along the cooled PV array.