Efficient Artificial Lighting System For Surface Mine Haul Roads

Haul roads within the pit are one of the critical areas in surface mines where lighting installations are not permanent due to regular advancement of the working face. Due to this reason it is very difficult to maintain the lighting standards, as specified by various regulatory bodies. Lighting in mines presents special problems because of the dark surroundings and low surface reflectance. Hence, scientific design of artificial lighting is very important to achieve the minimum required lighting standards. Authors developed software, named SURLux, in MATLAB for design of illumination system, which incorporates all the design parameters. It also computes the total cost of the lighting system. In this paper a 1.0 km stretch of haul road is designed for four different types of sources namely, 150 and 250 W high pressure mercury vapor lamps (HPMV), and 150 and 250 W high pressure sodium vapor lamps (HPSV), at various pole heights (8, 10, 12, 14 and 16 m). From the results of the study it is observed that with 16 m height pole the total annual cost for 150 W HPSV is the minimum (Rs. 87,739/-). In most of the cases the cost is high with HPMV lamps. This is mainly because of their shorter life and relatively more number of poles. In general, lamp selection is made mainly based on efficacy and suitability to each situation. However, among the feasible alternatives for any project, the variant that offers the minimum total cost is finally selected.