A. A. Elfar^{1, 2,}, A. F. Elngar³, K. Cipri⁴, M. H. Hassan¹

The harsh environmental factors like temperature, rainfall and humidity usually affect the performance of solar power systems and, accordingly, the overall systems reliability. An outdoor power station is an example of the systems dramatically affected by such harsh environmental factors. The objective of this research is to explore the effects of the environmental factors on the overall maintenance performance of an outdoor solar power station system and the system overall design. Maintenance performance is measured by some indicators such as the failure rate (FR) and mean time to repair (MTTR) for some selected outdoor solar power station subsystems. An analytical regression model based on a set of collected field data is developed. The insignificant affecting variables are cancelled based on the regression coefficients P-value. A mean time between failures MTBF-based comparison for some sub-systems that could be installed either indoor or outdoor is conducted. A new mathematical model is introduced to describe the relationship between the sub-systems failure modes due to environmental factors and the system configuration. The verified model may guide the maintenance planners. Also, the results can be used to distinguish between indoor and outdoor system maintenance and why the system is promoted to be installed indoor or outdoor.

Outdoor Power Systems, MTBF, Preventive maintenance, system configuration, regression models