The aim of this study is to investigate the heat transfer and flow dynamics in inclined PV panels. For this purpose, a numerical study of the early stage regime of natural convection flow in an inclined plane channel asymmetrically heated at a 510 W/m(2) uniform heat flux, corresponding to the average annual solar heat flux in France, has been performed. Numerical simulations are presented for two-dimensional, laminar and unsteady flow using the finite volume approach. The results showed appearance of large-scale flow instabilities which will develop and propagate until the development of a pocket-like vortex (reversed flow). Moreover, for large channel inclination angles (alpha = +20 degrees and alpha = -20 degrees with regard to the vertical position) the heat transfer rate is shown to be low. The maximal increase and decrease in mass flow rate are 7% for alpha = -20 and 21% for alpha = +20 degrees respectively, compared to that of vertical channel. (C) 2017 Elsevier Ltd. All rights reserved.