Iran is recognized as one of the largest fossil fuel reserve resources in the world, but it is also suffering from mismanaged consumption. The consequences of this mismanagement have been considered in Iran during recent years and authorities have raised concerns about it. Identification of the optimized orientation and tilt angle for roofs in BandarAbbas -South of Iran- in order to achieve the maximum daytime ray gain by photovoltaic cells is the main purpose of this paper. This paper makes a comparison in three types of facade angles in BandarAbbas (90 °, 80 ° and 70 °). The results show that 70 ° facade is the most efficient wall in order to gain energy in BandarAbbas.