pvlib.spectrum.get_reference_spectra#
- pvlib.spectrum.get_reference_spectra(wavelengths=None, standard='ASTM G173-03')[source]#
Read a standard spectrum specified by
standard
, optionally interpolated to the specified wavelength(s).Defaults to
ASTM G173-03
AM1.5 standard [1], which returnsextraterrestrial
,global
anddirect
spectrum on a 37-degree tilted surface, optionally interpolated to the specified wavelength(s).- Parameters:
wavelengths (numeric, optional) – Wavelengths at which the spectrum is interpolated. [nm]. If not provided, the original wavelengths from the specified standard are used. Values outside that range are filled with zeros.
standard (str, default "ASTM G173-03") – The reference standard to be read. Only the reference
"ASTM G173-03"
is available at the moment.
- Returns:
standard_spectra (pandas.DataFrame) – The standard spectrum by
wavelength [nm]
. [W/(m²nm)]. Column names areextraterrestrial
,direct
andglobal
.
Notes
If
wavelength
is specified, linear interpolation is used.If the values in
wavelength
are too widely spaced, the integral of each spectrum may deviate from its standard value. For global spectra, it is about 1000.37 W/m².The values of the ASTM G173-03 provided with pvlib-python are copied from an Excel file distributed by NREL, which is found here [2]: https://www.nrel.gov/grid/solar-resource/assets/data/astmg173.xls
Examples
>>> from pvlib import spectrum >>> am15 = spectrum.get_reference_spectra() >>> am15_extraterrestrial, am15_global, am15_direct = \ >>> am15['extraterrestrial'], am15['global'], am15['direct'] >>> print(am15.head()) extraterrestrial global direct wavelength 280.0 0.082 4.730900e-23 2.536100e-26 280.5 0.099 1.230700e-21 1.091700e-24 281.0 0.150 5.689500e-21 6.125300e-24 281.5 0.212 1.566200e-19 2.747900e-22 282.0 0.267 1.194600e-18 2.834600e-21
>>> am15 = spectrum.get_reference_spectra([300, 500, 800, 1100]) >>> print(am15) extraterrestrial global direct wavelength 300 0.45794 0.00102 0.000456 500 1.91600 1.54510 1.339100 800 1.12480 1.07250 0.988590 1100 0.60000 0.48577 0.461130
References