Optimal distribution of PV modules on roofs with limited space

The present work proposes a new algorithm for finding the optimal distribution of PV modules on flat roofs of urban building so that the total absorbed energy is maximised. The paper is divided in 3 sections. Section 1 shows an analytic technique that allows for annual irradiation of a PV module to be calculated for every tilt angle, consequently, this procedure can also be used to determine the optimal tilt that maximises the total irradiation of such module. In Section 2, a new packing algorithm is developed (specifically for this problem) so that total area of the PV modules of the flat roof is maximised. Studying the shadowing between modules and the needed spacing is key for this part. Lastly, in Section 3, it’s checked whether modifying the fixed tilt of the PV modules to be installed in a flat roof results in an increase of the total PV surface that compensates the loss of energy per module deriving from not using the optimal tilt angle, so that the maximum possible total absorbed energy for a given terrace is achieved.