The Solar Energy industry relies on standardization for many things, including testing energy conversion, reflectance or materials properties, fabricating arrays, integrating into the smart grid, or assuring workplace safety.
Its use is mandatory for the calibration of secondary standard pyranometers according to ISO 9060, and is recommended for the calibration of pyranometers which are used as reference instruments in comparisons. Is intended for use by test institutions or test laboratories equipped with well-maintained pyrheliometers and is applicable to all pyranometers. The object is to promote the uniform application of reliable methods to calibrate pyranometers, since accurate calibration factors are the basis of accurate hemispherical solar radiation data which are needed for solar energy test applications or simulations.
This document specifies two preferred methods for the calibration of pyranometers using reference pyranometers; indoor (Type A) and outdoor (Type B). Indoor or type A calibration, is performed against a lamp source, while the outdoor method B, employs natural solar radiation as the source. Indoor calibration is performed either at normal incidence (type A1), the receiver surface perpendicular to the beam of the lamp or under exposure to a uniform diffuse lamp source using an integrating sphere (type A2). Outdoor calibration is performed using the sun as a source, with the pyranometer in a horizontal position (type B1), in a tilted position (type B2), or at normal incidence (type B3). Calibrations according to the specified methods will be traceable to SI, through the world radiometric reference (WRR), provided that traceable reference instruments are used. This document is applicable to most types of pyranometers regardless of the type technology employed. The methods have been validated for pyranometers that comply with the requirements for classes A, B and C of ISO 9060 . In general, all pyranometers may be calibrated by using the described methods, provided that a proper uncertainty evaluation is performed. Unlike spectrally flat pyranometers, non-spectrally flat pyranometers might have a spectral response that varies strongly with the wavelength even within the spectral range from 300 to 1 500 nm, and therefore the calibration result may possibly be valid under a more limited range of conditions. The result of a calibration is an instrument sensitivity accompanied by an uncertainty. This document offers suggestions for uncertainty evaluation in the annexes.
This International Standard describes the calibration of field pyrheliometers using reference pyrheliometers and sets out the calibration procedures and the calibration hierarchy for the transfer of the calibration. This International Standard is mainly intended for use by calibration services and test laboratories to enable a uniform quality of accurate calibration factors to be achieved.
This document provides an appropriate reference spectral irradiance distribution to be used in determining relative performance of solar thermal, photovoltaic, and other systems, components and materials where the direct or hemispherical irradiance component is desired. This document provides one reference hemispherical irradiance spectrum, one reference direct normal irradiance spectrum and 171 subordinate hemispherical tilted irradiance spectra. The reference spectral irradiance presented in this document defines an air mass 1,5 solar spectral irradiance, for use in solar applications where a reference spectral irradiance is required, for the direct normal radiation 5,8° field-of-view angle and hemispherical radiation on an equator-facing, 37° tilted plane for albedo corresponding to a light sandy soil. The reference spectral irradiance are intended to represent ideal clear sky conditions. The reference spectra and the subordinate spectral irradiances representing different sky conditions are provided in .xls files available at https://standards.iso.org/iso/9845/-1/ed-2/en/