View factors of photovoltaic collectors on Roof Tops

被引:20
作者
Appelbaum, J. [1 ]
Aronescu, A. [1 ]
机构
[1] Tel Aviv Univ, Sch Elect Engn, IL-69978 Tel Aviv, Israel
关键词
MONTE-CARLO METHOD; DESIGN; FIELD;
D O I
10.1063/1.4943122
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
The diffuse radiation is an important component of the global radiation affecting the output of photovoltaic (PV) collectors. This radiation depends on the view factor between the collector and sky. A simple expression for the view factor for single inclined collectors on a horizontal plane is known. However, for a photovoltaic solar field with multiple rows deployed on a horizontal or on inclined planes, the view factor is more complicated to calculate, because a collector row may obscure part of the sky for the adjacent row. More complication is added for collectors deployed on saw-tooth roofs. The present study deals with the calculation of view factors to sky for collectors deployed in multiple rows and in the presence of obscuring structures on roof tops. General and particular mathematical expressions for view factors to sky were developed for PV collectors deployed on grounds or on roof tops to determine the diffuse incident solar radiation on PV collectors, and numerical values of view factors were presented. The view factor to sky depends significantly on the inclination angle of the collector. For common deployment of collectors in multiple rows on horizontal planes, the view to sky is in the range between 0.8 and 0.9 for 30 degrees inclination angle, whereas for 50 degrees inclination angle, the range is between 0.6 and 0.7. The effect of the distance between collectors on the view factor is less pronounced. A wall or a fence in front of the collector may decrease significantly the view factor to sky; an increase of 1.0 to 3.0 m decreases the view to sky from 0.8 to 0.6 for 30 degrees inclination, and from 0.7 to 0.4 for 50 degrees inclination. The view factor to sky of vertical collectors is less than 0.5. (C) 2016 AIP Publishing LLC.
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页数:12
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共 20 条
  • [1] Bifacial photovoltaic panels field
    Appelbaum, J.
    [J]. RENEWABLE ENERGY, 2016, 85 : 338 - 343
  • [2] THE EFFECT OF SHADING ON THE DESIGN OF A FIELD OF SOLAR COLLECTORS
    BANY, J
    APPELBAUM, J
    [J]. SOLAR CELLS, 1987, 20 (03): : 201 - 228
  • [3] Determination of view factors by contour integral technique
    Bopche, Santosh B.
    Sridharan, Arunkumar
    [J]. ANNALS OF NUCLEAR ENERGY, 2009, 36 (11-12) : 1681 - 1688
  • [4] Howell J.R., 1982, A Catalogue of Radiation Configuration Factors
  • [5] SHADING EFFECTS OF COLLECTOR ROWS TILTED TOWARD THE EQUATOR
    JONES, RE
    BURKHART, JF
    [J]. SOLAR ENERGY, 1981, 26 (06) : 563 - 565
  • [6] An Optimization Method for Designing Large PV Plants
    Kerekes, Tamas
    Koutroulis, Eftichis
    Sera, Dezso
    Teodorescu, Remus
    Katsanevakis, Markos
    [J]. IEEE JOURNAL OF PHOTOVOLTAICS, 2013, 3 (02): : 814 - 822
  • [7] Klise G.T., 2009, Models used to assess the performance of photovoltaic systems, P1
  • [8] View factors of photovoltaic collector systems
    Maor, T.
    Appelbaum, J.
    [J]. SOLAR ENERGY, 2012, 86 (06) : 1701 - 1708
  • [9] Martinez I., 1995, Radiative View Factors
  • [10] Monte Carlo method for calculating local configuration factor for the practical case in material processing
    Mirhosseini, M.
    Saboonchi, A.
    [J]. INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER, 2011, 38 (08) : 1142 - 1147