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Sunbelt Spectra comparison with Standard ASTM G173: the Chilean case

Authors:
Aitor Marzo at University of Granada
Aitor Marzo
Jesus Polo at Centro Investigaciones Energéticas, Medioambientales y Tecnológicas
Jesus Polo
Stefan Wilbert at German Aerospace Center (DLR)
Stefan Wilbert
Chris Gueymard at Solar Consulting Services
Chris Gueymard
  • Solar Consulting Services
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Abstract and Figures

Two spectra of solar direct normal irradiance (including circumsolar) are estimated based on spatio-temporal averages of the relevant atmospheric parameters extracted from two different databases: MODIS satellite sensor retrievals and AERONET sun photometer network. The satellite database is used to calculate an average spectrum for the area of the Atacama Desert. The AERONET database is used for two purposes: (i) to apply bias-removal linear methods to correct the MODIS parameters over Atacama, and (ii) to calculate an average local spectrum for the Paranal station. The SMARTS radiative transfer model is used to obtain the three spectra developed in this study. Both the Atacama and Paranal spectra are compared against each other and also to the world reference, ASTM G173. In one of the cases, significant differences are found for short wavelengths. In order to quantify the relative importance of these spectral differences, the propagation of errors due to the use of each spectrum is evaluated for CSP applications over the Atacama Desert, considering twelve different scenarios involving the reflectance, transmittance or absorptance of various materials.
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Sunbelt spectra comparison with standard ASTM G173: The Chilean case
Aitor Marzo, Jesús Polo, Stefan Wilbert, Christian A. Gueymard, Wilko Jessen, Pablo Ferrada, Joaquín Alonso-
Montesinos, and Jesús Ballestrín
Citation: AIP Conference Proceedings 2033, 190010 (2018); doi: 10.1063/1.5067195
View online: https://doi.org/10.1063/1.5067195
View Table of Contents: http://aip.scitation.org/toc/apc/2033/1
Published by the American Institute of Physics
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Supplementary resource (1)

Marzo-Sunbelt Spectra Atacama Chile poster-SolarPACES17
Data
September 2017
Aitor Marzo · Jesus Polo · Stefan Wilbert · Chris Gueymard · Jesús Ballestrín
... The resolution of each measured parameter was 1s and was recorded as an average value per minute. [38], c) Picture was taken by MODIS-Terra instrument from space, on August 23 th , 2022 (http://aeronet.gsfc.nasa.gov). The red square highlights the Calama location. ...
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... • Definition of reference spectra to improve the design of PV cells and other devices, or their testing (Case et al., 2008;Gueymard et al., 2002;Jessen et al., 2018;Marzo et al., 2018;Myers et al., 2004;Ripalda et al., 2018). ...
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