Mohammad Tahsildoost

Document Type : Original Article


1 Assistant Professor, Faculty of Architecture and Urban Planning, Shahid Beheshti University

2 MSc, Architecture Technology, Faculty of Architecture and Urban Planning, Shahid Beheshti University


The growing levels of fossil fuel consumption in recent years has caused irrecoverable damages to the environment. The global pollution crisis and the increasingly dwindling levels of unrenewable energy reserves have prompted experts to seek clean, suitable replacements for fossil fuels. On the other hand, with the recent technological developments and increasingly efficient methods of using renewable energies, there has grown a tendency in sciences towards using such renewable resources. Of particular importance among these resources is solar energy, specially through photovoltaic panels. This is due to the ease of access and use in many parts of the globe, including most parts of Iran. The use of these panels has gone so far as to be considered as an integrated part of sustainable buildings, with their use significantly on the increase. Naturally, the demand for increased efficiency of these tools has required studies on effective efficiency factors. These include particularly important studies on the positioning angles of panels on different facets of the building (both horizontal and vertical), and on their shading on one another when used as building elements. The present paper adopts a parametric method along with software capabilities of these plug-ins in Grasshopper in order to programme and calculate optimised titling angles for solar settings in vertical (wall-mounted), pitched (pitched roof-mounted), horizontal (ground- and flat roof-mounted) positions and in various building orientations, and to define numeric indices to work out the necessity and importance of the optimised angle. The next step was to assess the reliability of calculations and thereby verify the method.
The method was then applied to the case of Tehran to establish optimised tilting angles for a certain vertical panel setting in different orientations with the importance of optimised angles reported through a chart. In conclusion, it was proved that the use of optimised tilting angle for west- and east-facing walls is significantly more than for south-facing wall.


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