Prepare the solar position, irradiance, and weather inputs to the model, starting with GHI, DNI and DHI.


weather (DataFrame, or tuple or list of DataFrames) –

Required column names include 'dni', 'ghi', 'dhi'. Optional column names are 'wind_speed', 'temp_air', 'albedo'.

If optional columns 'wind_speed', 'temp_air' are not provided, air temperature of 20 C and wind speed of 0 m/s will be added to the weather DataFrame.

If optional column 'albedo' is provided, albedo values in the ModelChain’s PVSystem.arrays are ignored.

If weather is a tuple or list, it must be of the same length and order as the Arrays of the ModelChain’s PVSystem.

  • ValueError – If any weather DataFrame(s) is missing an irradiance component.

  • ValueError – If weather is a tuple or list and the DataFrames it contains have different indices.

  • ValueError – If weather is a tuple or list with a different length than the number of Arrays in the system.


Assigns attributes to results: times, weather, solar_position, airmass, total_irrad, aoi, albedo.