Analysis of diffuse radiation data for Beer Sheva: Measured (shadow ring) versus calculated (global-horizontal beam) values

Journal Article · Wed Dec 01 00:00:00 EST 1993 · Solar Energy (Journal of Solar Energy Science and Engineering); (United States)

DOI:https://doi.org/10.1016/0038-092X(93)90134-A· OSTI ID:5510622

Kudish, A I ^[1]; Ianetz, A ^[2]

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1. Ben-Gurion Univ. of the Negev, Beer Sheva (Israel)
2. Israel Meteorological Service, Bet Dagan (Israel)

The authors have utilized concurrently measured global, normal incidence beam, and diffuse radiation data, the latter measured by means of a shadow ring pyranometer to study the relative magnitude of the anisotropic contribution (circumsolar region and nonuniform sky conditions) to the diffuse radiation. In the case of Beer Sheva, the monthly average hourly anisotropic correction factor varies from 2.9 to 20.9%, whereas the [open quotes]standard[close quotes] geometric correction factor varies from 5.6 to 14.0%. The monthly average hourly overall correction factor (combined anisotropic and geometric factors) varies from 8.9 to 37.7%. The data have also been analyzed using a simple model of sky radiance developed by Steven in 1984. His anisotropic correction factor is a function of the relative strength and angular width of the circumsolar radiation region. The results of this analysis are in agreement with those previously reported for Quidron on the Dead Sea, viz. the anisotropy and relative strength of the circumsolar radiation are significantly greater than at any of the sites analyzed by Steven. In addition, the data have been utilized to validate a model developed by LeBaron et al. in 1990 for correcting shadow ring diffuse radiation data. The monthly average deviation between the corrected and true diffuse radiation values varies from 4.55 to 7.92%.

• OSTI ID: 5510622
• Journal Information: Solar Energy (Journal of Solar Energy Science and Engineering); (United States), Vol. 51:6; ISSN 0038-092X
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ANISOTROPY
CORRECTIONS
DIFFUSE SOLAR RADIATION
DATA ANALYSIS
NUMERICAL ANALYSIS
DEAD SEA
ISRAEL
MATHEMATICAL MODELS
PYRANOMETERS
ASIA
DEVELOPING COUNTRIES
EQUIPMENT
LAKES
MATHEMATICS
MEASURING INSTRUMENTS
MIDDLE EAST
RADIATIONS
SOLAR EQUIPMENT
SOLAR FLUX
SOLAR RADIATION
STELLAR RADIATION
SURFACE WATERS
540110*
540150 - Environment
Atmospheric- Site Resources & Use Studies- (1990-)