PVsyst
PVsyst is a software package for the design, simulation, and analysis of photovoltaic PV systems. It supports grid-connected, off-grid, and batteryless configurations and is widely used by engineers, researchers, and installers to estimate energy production, assess performance, and aid in project development. The program models electrical and meteorological inputs to produce annual energy yields and performance indicators.
PVsyst provides modules and inverters libraries, allows users to specify system geometry (tilt, azimuth, array layout)
The calculation engine combines PV module models, inverter efficiency curves, and loss factors such as soiling,
PVsyst is a commercial tool with ongoing development, widely cited in industry and academia for PV system