Cairo metro lines are one of the main electrical transport mode in the city and depends mainly on traditional sources of energy. Due to the energy and environmental world crisis, the research examines the potential use of region solar energy by covering the route of the first metro line in Cairo with solar system to substitute a traditional electricity portion used.The research proposed a three phase simulation modelling. Phase one the Ideal Solar System ISS, for evaluate the feasibility and the efficient solar system to be used. Phase two proposed the Solar Energy Reduction Simulation Model SERSM due to the urban and environment conditions. The proposed SERSM simulate the shadow cast within the environment conditions on metro line representing urban conditions by the track aspect ratio. Phase three conducts a detailed field survey for an action area for spatially validate SERSM phase two results of solar energy reduction. The research shows the potential and the feasibility of using the solar energy to substitute a portion of used traditional energy sources of the metro line where 34.5 km length can be covered and expected to produce about 7500 MW/month, equivalent to 50-60% of the electricity consumption of the line. DOI: http://dx.doi.org/10.5755/j01.erem.75.1.21747