pvdeg.degradation.degradation_spectral#
- pvdeg.degradation.degradation_spectral(spectra: Series, rh: Series, temp: Series, wavelengths: int | ndarray, time: Series, Ea: float = 0.0, n: float = 0.0, p: float = 0.6, C2: float = 0.07, R_0: float = 1.0) float[source]#
Compute degradation as double integral of Arrhenius (Activation Energy, RH, Temperature) and spectral (wavelength, irradiance) functions over wavelength and time.
- Parameters:
spectra (pd.Series type=Float) – front or rear irradiance at each wavelength in “wavelengths” [W/m² nm]
rh (pd.Series type=Float) – RH, time indexed [%]
temp (pd.Series type=Float) – temperature, time indexed [°C]
wavelengths (int-array) – integer array (or list) of wavelengths tested w/ uniform delta in nanometers [nm]
time (time indicator in [h]) – if not included it will assume 1 h for each dataframe entry.
Ea (float [kJ/mol]) – Arrhenius activation energy. The default is 0 ofr no dependence
n (float) – Power law fit paramter for RH sensitivity. The default is 0 for no dependence.
p (float) – Power law fit parameter for irradiance sensitivity. Typically 0.6 +- 0.22. Here it is applied separately for each wavelength bin.
C2 (float) – Exponential fit parameter for sensitivity to wavelength. Typically 0.07 [1/nm]
R_0 (float) – Prefactor for degradation. Units can vary, but would be something like [%/h] Default 1.0
- Returns:
degradation (float) – Total degradation over time and wavelength. Units are determined from R_0 and time.