PVsyst is described as 'Photovoltaic simulation and design software offering detailed system sizing, comprehensive energy yield analysis, shading and loss modeling, economic evaluation, and flexible component selection' and is a 3D Modeler in the photos & graphics category. There are five alternatives to PVsyst for Windows, Web-based and SaaS. The best PVsyst alternative is Ashampoo Home Design. It's not free, so if you're looking for a free alternative, you could try PVSketch. Other great apps like PVsyst are Graphisoft DDScad, Solarius PV and OpusFlow.