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Title: Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation

Abstract

Accurate solar radiation measurements using pyranometers are required to understand radiative impacts on the Earth's energy budget, solar energy production, and to validate radiative transfer models. Ventilators of pyranometers, which are used to keep the domes clean and dry, also affect instrument thermal offset accuracy. This poster presents a high-level overview of the ventilators for single-black-detector pyranometers and black-and-white pyranometers. For single-black-detector pyranometers with ventilators, high-flow-rate (50-CFM and higher), 12-V DC fans lower the offsets, lower the scatter, and improve the predictability of nighttime offsets compared to lower-flow-rate (35-CFM), 120-V AC fans operated in the same type of environmental setup. Black-and-white pyranometers, which are used to measure diffuse horizontal irradiance, sometimes show minor improvement with DC fan ventilation, but their offsets are always small, usually no more than 1 W/m2, whether AC- or DC-ventilated.

Authors:
; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies Office (EE-3B)
OSTI Identifier:
1358690
Report Number(s):
NREL/PO-5D00-68517
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: Presented at the NOAA ESRL Global Monitoring Annual Conference 2017, 23-24 May 2017, Boulder, Colorado
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; solar radiation; measurement; pyranometer; single-black-detector; black-and-white; ventilator

Citation Formats

Kutchenreiter, Mark, Michalski, J.J., Long, C.N., and Habte, Aron. Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation. United States: N. p., 2017. Web.
Kutchenreiter, Mark, Michalski, J.J., Long, C.N., & Habte, Aron. Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation. United States.
Kutchenreiter, Mark, Michalski, J.J., Long, C.N., and Habte, Aron. Mon . "Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation". United States. doi:. https://www.osti.gov/servlets/purl/1358690.
@article{osti_1358690,
title = {Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation},
author = {Kutchenreiter, Mark and Michalski, J.J. and Long, C.N. and Habte, Aron},
abstractNote = {Accurate solar radiation measurements using pyranometers are required to understand radiative impacts on the Earth's energy budget, solar energy production, and to validate radiative transfer models. Ventilators of pyranometers, which are used to keep the domes clean and dry, also affect instrument thermal offset accuracy. This poster presents a high-level overview of the ventilators for single-black-detector pyranometers and black-and-white pyranometers. For single-black-detector pyranometers with ventilators, high-flow-rate (50-CFM and higher), 12-V DC fans lower the offsets, lower the scatter, and improve the predictability of nighttime offsets compared to lower-flow-rate (35-CFM), 120-V AC fans operated in the same type of environmental setup. Black-and-white pyranometers, which are used to measure diffuse horizontal irradiance, sometimes show minor improvement with DC fan ventilation, but their offsets are always small, usually no more than 1 W/m2, whether AC- or DC-ventilated.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon May 22 00:00:00 EDT 2017},
month = {Mon May 22 00:00:00 EDT 2017}
}

Conference:
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