Experimental and numerical assessment of photovoltaic collectors performance dependence on frame size and installation technique

The performance of a solar photovoltaic silicon panel is inversely proportional to its operating temperature. Therefore the overheating risk must be avoided in order to improve the cells electric efficiency. The temperature increase in a solar cell also gives rise to thermal stresses within the module. In this work the authors propose an experimental and numerical investigation of photovoltaic collectors temperature and efficiency dependence on main design parameters (thickness of the aluminum frame), installation technique (distance between photovoltaic panel and supporting panel, tilt angle of the module), and environmental operating conditions, with particular reference to the wind velocity. Experimental investigations have been conducted on a two photovoltaic modules assembly composed by silicon panels. Numerical simulations have been performed employing a two-dimensional finite element numerical model, validated against experiments carried out by the authors. The validated numerical tool has been applied to evaluate photovoltaic collector performance dependence on panel geometrical parameters, installation procedure and operating conditions. The main objective of the present paper is to provide installation and operating indications in order to maximize efficiency. From the conducted investigations it has been evidenced that an optimal distance of the panel from the support can be found, corresponding to which the efficiency is maximized.