A Case Study for Tunnel Lighting Lifetime Account

Abstract

A lighting device is required to provide minimum lighting level during the operating time. Contamination on lighting device causes luminous flux to be lost in lamp and structural imperfections to be formed on the surface of optical elements. This deficiency in the performance of lighting makes maintenance of lighting devices necessary. This effect formed by the common effect of various parameters and implemented periodically is called maintenance factor. Maintenance factor varies by lighting system, environmental conditions and features of luminaires. In this study, calculation of maintenance factors by years and change of lighting levels by different maintenance factors have been analyzed for high-pressure sodium vapour luminaries in tunnel lighting. Accordingly, increasing the maintenance factor used as multiplier in performance calculations will decrease the energy consumed. Therefore, increasing the Maintenance Factor increases the lighting efficiency.