Optimal Slope-Angles to Determine Maximum Solar Energy Gain for Solar Collectors Used in Iran

Abstract

The aim of this paper is providing atlases to determine maximum solar energy gain and optimum slope angle of solar collectors for Iran. To achieve this purpose, first, the daily, monthly, seasonally and yearly optimum slope and azimuth angles of solar collectors are determined for 30 Iranian cities and the gain of energy is calculated in the mentioned conditions. Then, the atlas of the optimum slope angle and the contour atlas of the maximum energy gain is provided. The Geographic Information System (GIS) is used to outline the maps. These atlases are essentials tools to find the best location for constructing different solar systems. The results show that the energy gain of the collector when it is adjusted at the daily optimum slope angle is almost the same compared with the case at the monthly optimum slope angle. Therefore, the map is provided for the energy gain when the collectors are mounted at the monthly optimum slope angle. The map of optimum slope angle is outlined for the fixed collector used for the entire year due to the high use of fixed collectors. Furthermore, the results show that Iran can be divided into five zone and the areas with the same latitude and climate have almost the same optimum slope angle.

Keywords

• Solar energy; Solar collectors; Slope angle; Atlas; Geographic Information System

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