2024-03-29T05:10:15Zhttps://riubu.ubu.es/oai/requestoai:riubu.ubu.es:10259/47562021-11-10T09:38:27Zcom_10259_4393com_10259_5086com_10259_2604col_10259_4394
Shadow-band radiometer measurement of diffuse solar irradiance: Calculation of geometrical and total correction factors
Simón Martín, Miguel de
Diez Mediavilla, Montserrat
Alonso Tristán, Cristina
Solar diffuse irradiance
Shadow-band
Instrumentation
Correction factor
Ingeniería eléctrica
Electric engineering
Among the various methods of measuring diffuse solar irradiance, shadowing devices are ones of the
most commonly used in solar research all over the world. These instruments work with a basic pyranometer,
properly calibrated for the measurement of solar irradiance, with a shadowing element, which
can be a disk or a band (Drummond’s shadow-band), that prevents the direct incidence of solar beam
irradiance on the sensor. This method is capable of precise measurements, but sensor outputs have to
be corrected, so as to quantify the amount of diffuse irradiance that the band blocks from reaching the
sensor. Several authors have advanced different expressions for this correction factor, most of which only
apply to horizontal and equator-oriented tilting pyranometers. In this work, we present a general
approach to calculate the geometrical correction factor for a tilted sensor, oriented towards all possible
azimuth and zenith angles, which permits the measurement of solar diffuse irradiance on any tilted and
oriented surfaces. Furthermore, five total correction models are adapted for measurement in any given
direction and evaluated on vertical walls pointing the four cardinal directions. Our results show that geometrical
correction improves the Mean Bias Difference (MBD), the Root Mean Squared Difference (RMSD)
and the l0:99 statistics by 60%, 62% and 56%, respectively, in contrast with the raw data. The LeBaron et al.
model gives the most accurate figure for total correction according to MBD, RMSD and l0:99 statistics,
with promising average performances of 97%, 91%, and 96%, respectively
Spanish Government (grant ENE2011-27511)
2018-03-20T09:34:42Z
2018-12-01T03:45:06Z
2016-12
info:eu-repo/semantics/article
info:eu-repo/semantics/acceptedVersion
0038-092X
http://hdl.handle.net/10259/4756
10.1016/j.solener.2016.09.026
eng
Solar Energy. 2016, V. 139, p. 85-99
https://doi.org/10.1016/j.solener.2016.09.026
Attribution-NonCommercial-NoDerivatives 4.0 International
http://creativecommons.org/licenses/by-nc-nd/4.0/
info:eu-repo/semantics/openAccess
application/pdf
Elsevier