On Selecting Optimum Tilt Angle for Solar Photovoltaic Farms

Abstract

It has been more than 20 years, since the first manufacturers announced and extended, 25 year guarantee for solar photovoltaic panels. This event set the market standards which have not been disputed ever since. Although an increasing number of studies focus on the long-term aging process of the panels, the area is not fully explored. The approach of most investors is that solar projects should be developed to maximise electricity production, and much less attention is paid to lifetime expectancy or considering adverse effects of non-optimal tilt angles. Possible failures and malfunctions are already being put into focus, but the impact of tilt angles and other technical parameters on life expectancy and operation costs are still of secondary importance.

The aim of the present paper is to provide a broad review on impacts that affect productivity and lifetime expectancy of solar panels. As positive and negative effects are both found among these, quantification is also necessary. The authors compare the effects of seven different factors to provide a broader view on the importance of properly determining the tilt angle of solar photovoltaic panels. The effect of several factors is smaller above 30° tilt angles and do not decrease productivity beyond a certain level. In contrast, negative impacts that are shortening life expectancy, have much bigger effect on the system with this angle deployment, thus current installation practice is advised to be reviewed.