The Effect of Collector Azimuth on Inter-Row Shading in Photovoltaic Fields—A Comprehensive Point of View

Abstract

Rooftop buildings, mountain terrains, rivers, and lake beds may be oriented at different azimuths other than due south (in the northern hemisphere), on which photovoltaic (PV) systems may be installed. The present study presents a comprehensive point of view on the relation between the inter-row spacing and the inter-row shading in multiple-row collectors of PV fields; it analytically formulates the inter-row spacing and the associated shading losses for collectors deployed at any azimuth on horizontal, sloped-planed, and oriented toward the south and north, and is supported by the numerical results. Several criteria for the inter-row spacing are applied in the study; among them is a newly introduced criterion appropriate for the collectors deployed at a given azimuth. This study indicates that shorter spacing results in increased shading; minimum shading is obtained for collectors oriented toward the equator; inter-row spacing for maintenance purposes is used in limited dimensions of the PV fields and, usually, in optimal PV system designs; less shading occurs for systems deployed on sloped planes oriented toward the south; less shading is obtained for collectors based on the new criterion, where collectors are deployed at azimuth equal to the solar azimuth, and larger spacing is required for collectors deployed on northern slopes.