Energy Storage in Distribution System Planning and Operation: Current Status and Outstanding Challenges

It is no exaggeration to state that power systems presently undergo a paradigm shift. Driven by an urgent desire to mitigate the effects of global warming and a foreseen end to the world's fossil fuel resources, an increasing tendency toward renewable energies is fostered by the international community. On the other hand, distributed generation and electric vehicle adoption are altering load nature and profile. Therefore, energy storage (ES) becomes a necessity for its ability to bridge the gap between the dynamically changing supply and demand in addition to other ancillary services it can provide. Meanwhile, advances in smart grid technologies enable escalating the incorporation of new technologies with more efficient control schemes and energy management algorithms. This paper presents an overview on the employment of ES technologies in planning and operation of distribution systems through the literature survey. The problem of sizing and siting ES units in distribution systems is first introduced. The state of the art of the technology is summarized, and some outstanding issues to be addressed through future research are highlighted.