Abstract: Electrical power from the grid is unreliable in Nigeria. This has forced mobile telecommunication operators to depend mainly on diesel generators. In this research, solar PV system is considered as an alternative power supply option. The PV system to power a Base Transceiver Station (BTS) was sized then Life Cycle Cost (LCC) method of economic assessment was used to compare the cost with the costs of diesel generator and grid utility over the life cycle period of the PV system which is 30 years. The LCC of PV system is $0.84/kWh that of diesel generator, $1.8/kWh and grid utility, $0.063/kWh. Sensitivity, analysis was carried out using variations in module costs, diesel fuel escalation and grid utility escalation. The results suggest that the PV system is cheaper than the diesel generator and could be the best option out of the three in the future.