Review of Optimization Techniques for Sustainable Microgrid System Operations: Current Status and Future Directions

Microgrids generally offer a promising and scalable means of providing clean, reliable and affordable energy for consumers in pursuit of Sustainable Development Goal 7 (SDG 7) of United Nations. However, sustainable microgrids operation depends on a number of factors ranging from technical to non-technical hence, the operation and sustainability of microgrids could be quite challenging. To enhance the sustainable operation of microgrids, the traditional approach is to cater for it at the design stage by overrating the design or design for complementary system. However, this approach is cost-intensive and does not perform optimally. Hence, the use of optimization techniques has been recently employed to enhance energy efficiency, reduce costs and improve reliability. The choice of optimization technique for a particular microgrid operation varies depending on the nature, types and configuration of the microgrid. This study therefore examines various microgrid configurations and the optimization techniques currently used for optimal and sustainable operation of microgrids. The study also provides future directions for micro gridsystem designer and operators to equip them with requisite information on the optimization technique for different applications. This study further pursues the realization of SDG 7 through energy sufficiency obtainable from sustainable operation of microgrid systems and will serve as a guide for microgrid system planners and operators.