pvlib.irradiance.louche#

pvlib.irradiance.louche(ghi, solar_zenith, datetime_or_doy, max_zenith=90)[source]#

Determine DNI and DHI from GHI using the Louche model.

Parameters:

ghi (numeric) – Global horizontal irradiance, see ghi. [Wm⁻²]
solar_zenith (numeric) – True (not refraction-corrected) zenith angle. See solar_zenith. [°]
datetime_or_doy (numeric, pandas.DatetimeIndex) – Day of year or array of days of year e.g. pd.DatetimeIndex.dayofyear, or pd.DatetimeIndex.

Returns:

data (OrderedDict or DataFrame) – Contains the following keys/columns:

dni: the modeled direct normal irradiance, see dni.
[Wm⁻²]
dhi: the modeled diffuse horizontal irradiance, see dhi.
[Wm⁻²]
kt: Clearness index. Ratio of global to
extraterrestrial irradiance on a horizontal plane. [unitless]

References