Energy storage systems for renewable energy power sector integration and mitigation of intermittency

Currently, the electric power sector is looking forward towards increasing the bent for availability, reliability and security of energy supply to consumers. This pursuit has vehemently increased the intention for integrating renewable energy (RE) into the electricity sector as a strategy to curb the problem of energy deficiency especially in isolated off-grid settlements. However, the variability in the sources of RE supply coupled with conditional changes in the level of energy consumption with respect to time has brought to focus the necessity for energy storage systems (ESSs). Despite the stochastic nature of RE produced from solar and wind energy and to some extent hydro, interest in their exploitation is still growing high due to their sustainability regarding environmental receptiveness. Thus, this paper extensively reviews the state of the art of three different kinds of energy storage technologies (pumped hydroelectricity storage, batteries and fuel cells) suitable for the integration and management of intermittency in RE. Within the context of the review, advantages and disadvantages of the various technologies are also presented. Additionally, it also pin-points on the different areas of applications of ESSs for RE integration and offers review summary on factors to be considered for selecting appropriate energy storage technology for either commercial or domestic applications. Finally, the paper concluded that ESSs selection is based on performance characteristics and fuel source used whereas no single ESS can meet all the possible requirements to be called a supreme ESS.