Combining energy storage and real-time thermal ratings to solve distribution network problems: benefits and challenges

Abstract

Energy Storage Systems (ESS) are a combination of an energy storage medium, such as a battery or super capacitor, and a power electronic interface to allow power to be exchanged with an electrical network. Real-Time Thermal Ratings (RTTR) allows network operators to take advantage of the inherent variation in network capacity as environmental conditions fluctuate, leading to an increased rating the majority of the time. Both are emerging technologies which can provide substantial benefits to distribution network operators. They can reduce power constraints, aid in the integration of renewables, and increase network reliability and resilience. ESS are expensive to install, but they are dispatchable assets, and can provide reactive power support and voltage control to their local network. RTTR are comparatively inexpensive, but the additional capacity that is released is not dispatchable. These differences suggest that a combination of ESS and RTTR could provide robust, affordable solutions to distribution network problems that neither technology could solve in isolation. In this paper, we quantify the benefits of combining ESS and RTTR to solve distribution network problems. We demonstrate that the combination of technologies is a more effective solution to many network problems than either a conventional asset based solution, or using RTTR or ESS alone, and we identify technical and regulatory obstacles which must be overcome to harness the full potential of these, and other, emerging technologies.