EU PVSEC Programme Online
EU PVSEC 2021, 6 - 10 September 2021
Presentation: 5CV.3.4 Analysis of Electrical Shading Effects in PV Systems
Type: Visual
Date: Wednesday, 8th September 2021
15:15 - 16:45
Author(s): M. Oliosi, B. Wittmer, A. Mermoud
Presenter / Speaker: B. Wittmer, PVsyst, Satigny, Switzerland
Event: Conference Conference
Session: 5CV.3 PV Systems: Planning, Plant Optimisation Tools, Advanced Installation Criteria, Construction Issues / Concentrators and PV for S
Topic: 5. 2 Design and Installation of PV Systems
Keywords: Shading, PV System, Simulation, Software, Mismatch, Design
Summary / Abstract: In a PV system, partial shading of PV modules and strings leads to yield losses not only due to reduced irradiation, but also due to shaded PV cells limiting the current of a string. These so-called electrical shading losses contribute in a non-negligible way to the total losses in a PV system. The detailed calculation of these losses is nontrivial, since it is necessary to combine many IV curves from individual cell strings and determine the resulting curve which can have a much more irregular shape than the simple IV-curve of a group of unshaded strings. Hence, in-depth studies are required to understand and optimize the PV system design. In this work, we explain the different ways in which the PVsyst software handles the electrical shadings. The detailed IV-curve calculation and three simplified models are applied to different PV system configurations, and the impact of partial shadings on the energy yield is assessed. We discuss which calculation models should be used in different situations. By comparing the results for different typical string layouts, and PV module types, we derive some strategies for minimizing electrical shading losses, that can be applied in a general way.