Utility Scale Applications of Energy Storage

Power system operating conditions that are on the verge of being unsafe have encouraged utilities and power consumers to look for bulk energy storage systems. Various energy storage systems (ESSs) have excellent records and have been used for decades. This paper provides an overview of different energy storage technologies and their possible applications in power systems. The purpose of this analysis is to highlight combinations of technologies and applications with the highest benefit for the owner of the ESS. The analysis shows that frequency regulation and integration of renewables are the applications that most likely will be asked for by utilities in the future. Technologies which are most suitable for these applications include thermo-electric energy storage and batteries. These are technologies which are not restricted by their geographic footprint and offer payback times of five to ten years.