Methods for irradiance calculations

pvsystem.PVSystem.get_irradiance(...[, ...])	Uses pvlib.irradiance.get_total_irradiance() to calculate the plane of array irradiance components on the tilted surfaces defined by each array's surface_tilt and surface_azimuth.
pvsystem.PVSystem.get_aoi(solar_zenith, ...)	Get the angle of incidence on the Array(s) in the system.
pvsystem.PVSystem.get_iam(aoi[, iam_model])	Determine the incidence angle modifier using the method specified by iam_model.