Shading in IST PVSolar Simulator
IST PVSolar Simulator runs an hourly simulation of 8,760 steps a year. It models near shading in two ways: a 2D row-to-row calculation for regular rows, and a 12×24 shading table produced by its 3D roof tool for rooftops with obstacles. Its 15-minute mode divides each hour into four steps by interpolating the hourly weather. That is not the same as a true sub-hourly simulation, which needs weather measured or generated at 5 or 15 minutes. Other tools go further on two points. PVsyst 8.1 runs a true sub-hourly simulation and computes electrical mismatch from the position of every module in a 3D scene. HelioScope simulates at module level and can build the scene from LIDAR data. Two settings decide how far any yield number can be trusted: the time step and the shading model. This article explains what IST PVSolar Simulator does at each one, in plain terms, and when the simpler method is enough. The hourly run: 8,760 steps The standard simulation takes one typical year of hourly weat...