The Impact of Different Battery Technologies for Remote Microgrids

Energy storage systems are considered an effective solution for remote microgrids. They allow to increase the overall system reliability, performance, and reduce operational cost by increasing the energy utilization of renewable energy resources (PV and wind energy). A battery can reduce the system\u27s operational cost by matching a diesel generator with the load demand. There are many types of batteries which can be used in remote microgrids, such as Lead-acid, Lithium-ion, Zinc-bromine and Aqueous Hybrid Ion. By selecting a battery which provides low operational cost and longer battery life is complex, relying on many key technical features which affect the battery behavior, including efficiency, cost, and state of charge. This thesis presents the feasibility of different battery types in a remote microgrid, such as lithium ion, lead acid and unique batteries, which uses an energy management system (EMS). The EMS uses two layer power management system: 24 schedule day ahead and real time dispatch. The schedule layer uses a goal programing approach to combining two objectives fuel and the battery wear cost. The combined objective function was minimized. It has been validated this method through a simulation study of a microgrid using IBM CPLEX v12.6.1 optimization software. A desktop with 4 GB RAM and 3.00 GHz processor was used to solve the optimization problem (goal programming approach). The time for each yearly simulation result was about 3 hours. Weight plays a significant role in achieving the goal. The weights determine the use of the generators and batteries in the objective function. Therefore, selecting a weight set point can play a significant role to provide an efficient solution for an EMS. Battery wear cost is a key factor in designing the remote microgrid. The results showed the Tesla battery with EMS could provide 2.91% more cost effective than AHI, 4.99% than ZBB, 3.92% than lead acid, and 6% than lithium ion. Though the Tesla battery is of the lithium ion family, it is uniquely better than standard lithium ion due to its high capacity, round trip efficiency, small size, and 100% depth of discharge, which made it better than any lithium ion battery. Therefore, the Tesla battery is considered a unique battery. Also, using a Tesla battery with EMS can be 6% more cost effective than using normal lithium ion batteries. The Tesla battery, which has the lowest wear cost comparing to others, represents the most efficient solution for this study according to total operational cost of approximately $111,010 and nine year lifetime