Optimization of a Diesel System – Stockpiling for Supplying a Remote BTS Station

Abstract

Dedicated low-cost power supply to off-grid cell sites located in rural and suburban areas of Benin is the most difficult, as most rural areas are not connected to the national electricity grid. In these isolated sites the choice of the genset only as a power source is becoming increasingly difficult to justify both economically and environmentally, hence the need to design an optimal electrochemical energy storage system for powering these sites in combination with the genset. In this work we have developed a methodology for the optimization of the sizing of the system according to two criteria: the minimization of the consumption of the genset and the determination of the optimal parameters of the system (capacity of the genset to be installed and the storage capacity). The system was optimized by NSGA II type genetic algorithms on a load profile well suited to isolated sites. The results show two power supply possibilities depending on the battery technologies. For lead battery technology, a 15KVA group must be installed with a 48V/600Ah battery bank with 12 x 12V/200Ah batteries. For a system with lithium batteries, it will be necessary to install a 13KVA generator for the same storage capacity, i.e., 12 batteries of 16V/150Ah. From a technical point of view, the use of lithium batteries instead of lead batteries reduces the maximum consumption of the generator by 9.8L/day.