pvdeg.humidity.module#

pvdeg.humidity.module(weather_df, meta, tilt=None, azimuth=180, sky_model='isotropic', temp_model='sapm', conf='open_rack_glass_glass', WVTRo=7970633554, EaWVTR=55.0255, So=1.81390702, l=0.5, Eas=16.729, wind_factor=0.33)[source]#

Calculate the Relative Humidity of solar module backsheet from timeseries data.

Parameters:

weather_df (pd.DataFrame) – Weather data for a single location.
meta (pd.DataFrame) – Meta data for a single location.
tilt (float, optional) – Tilt angle of PV system relative to horizontal.
azimuth (float, optional) – Azimuth angle of PV system relative to north.
sky_model (str, optional) – Options: ‘isotropic’, ‘klucher’, ‘haydavies’, ‘reindl’, ‘king’, ‘perez’.
temp_model (str, optional) – Options: ‘sapm’, ‘pvsyst’, ‘faiman’, ‘sandia’.
mount_type (str, optional) –

Options: ‘insulated_back_glass_polymer’,
’open_rack_glass_polymer’ ‘close_mount_glass_glass’, ‘open_rack_glass_glass’
WVTRo (float) – Water Vapor Transfer Rate prefactor (g/m2/day). The suggested value for EVA is WVTRo = 7970633554(g/m2/day).
EaWVTR (float) – Water Vapor Transfer Rate activation energy (kJ/mol) . It is suggested to use 0.15(mm) thick PET as a default for the backsheet and set EaWVTR=55.0255(kJ/mol)
So (float) – Encapsulant solubility prefactor in [g/cm3] So = 1.81390702(g/cm3) is the suggested value for EVA.
l (float) – Thickness of the backside encapsulant (mm). The suggested value for encapsulat is EVA l=0.5(mm)
Eas (float) – Encapsulant solubility activation energy in [kJ/mol] Eas = 16.729(kJ/mol) is the suggested value for EVA.
wind_factor (float, optional) – Wind speed correction exponent to account for different wind speed measurement heights between weather database (e.g. NSRDB) and the tempeature model (e.g. SAPM) The NSRDB provides calculations at 2 m (i.e module height) but SAPM uses a 10 m height. It is recommended that a power-law relationship between height and wind speed of 0.33 be used. This results in a wind speed that is 1.7 times higher. It is acknowledged that this can vary significantly.

Returns:

rh_backsheet (float series or array) – relative humidity of the PV backsheet as a time-series