Mutual shading of PV modules on flat roofs: a parametric study

In order to make cities more resilient, our urban environment should not only consume energy, it should also become energy producing. Flat roofs are highly suitable for the placement of PV systems to produce renewable energy, but the assessment of its exact energy potential is not straightforward. Important configurations parameters of PV systems are the inclination and row distance, both leading to mutual shading. This study examined the technical and economic consequences of mutual shading of PV systems. In the first part, a comparison is performed between an unshaded module and a shaded module with different row distances and inclinations; in the second part, the energy output as well as payback times of a PV system on a flat roof were simulated. A significant decrease in energy production was seen due to mutual shading, while the configuration to achieve the maximum energy output was at an inclination of 0 degrees and a row distance of 0 metres. Payback calculations showed that, when electricity prices rise in the future, more options concerning inclination and row distance became feasible. (C) 2014 The Authors. Published by Elsevier Ltd.