Amin Khodakaram-Tafti - Ph.D Student, School of Mechanical Engineering, Shiraz University, Shiraz, Iran
Mahmood Yaghoubi - Professor, School of Mechanical Engineering, Shiraz University, Shiraz, Iran

This paper presents an experimental study of dust effect on the photovoltaic system performance for various tilt angle in residential area of Shiraz/Iran over a month (January 1, 2018 – February 3, 2018). Eight PV modules were installed on the roof of the Faculty of Mechanical Engineering, Shiraz University, at 0°, 15°, 30° and 45° with an azimuth angle of 0° (two PV module for each angle) in order to compare the performances of the cleaned and dusty modules. The results showed that the dust accumulation on the surface of the modules decreases their output power and reduction rate is strongly dependent on the tilt angle of the module. The average power reduction of modules with tilt angles of 0°, 15°, 30° and 45° due to dust accumulation in the last week of the test were 7.2%, 3.46%, 1.64% and 1.38%, respectively. It is not recommended to install PV panels at the tilt angles of 0° and 15° in this season and places where rainfall is abundant. Also, the best trade-off design alternative tilt angle, based on the maximum power output and minimum power reduction due to dust accumulation found to be 45° during the measuring period.

Dust accumulation, Photovoltaic, Output power, Performance analysis, Tilt angle