Estimates of uncertainty for measured spectra in the SERI spectral solar radiation data base

Abstract

The Solar Energy Research Institute's (SERI) Solar Radiation Resource Assessment Project collected spectral solar irradiance data and coincident insolation and meterological data from October 1986 to May 1988. This article describes the methods used to derive the wavelength-dependent measurement uncertainty for each spectral scan (i.e., spectra). We list the sources of uncertainty in calibration and field measurements, and present summaries of the magnitudes for each. Finally, we show derived uncertainty envelopes, representative of the 21 combinations of instruments, measurement modes, and measurement periods used during the project. Our results indicate uncertainly of greater than ±20% for the ultraviolet (300 to 400 nm), +5% to − 13% in the visible (400 to 900 nm), and + 8% to − 15% in the near infrared (900 to 1100 nm). Complete details of the analysis summarized here are available in separate SERI technical reports detailing the data base, its structure; and the uncertainty analysis.