I work in the PV industry, though I don't have much experience with weewx yet, and limited experience with python. That said, the calculation you are looking for is called a "transposition", and you are transposing from GHI (Global Horizontal Irradiance) from your horizontal sensor to what is called POA (Plane of Array) irradiance. That may help a bit with your searching.
Sandia's PV Array Performance Model is a set of equations that can describe nearly every part of a PV system's behavior: https://pvpmc.sandia.gov/modeling-steps/1-weather-design-inputs/plane-of-array-poa-irradiance/ It is partially (completely?) implemented in Python in the pvlib library: https://pvlib-python.readthedocs.io/en/stable/ I haven't used the library, though I do use a lot of tools that include calculations from the Sandia PVAPM. -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
