Reliability evaluation of energy storage systems combined with other grid flexibility options: A review

With the increasing penetration of renewable energy sources (RES) in conventional power systems, it has become very difficult to maintain balance between supply and demand due to the intermittent and variable nature of these resources. The integration of RES has a significant impact on system reliability and stability. Energy storage systems (ESS) offer a smart solution to mitigate output power fluctuations, maintain frequency, and provide voltage stability. The recent rapid development of energy storage technologies and their operational flexibility has led to increased interest in incorporating ESS in power systems to increase system reliability and economy. Additionally, other smart grid technologies such as dynamic thermal rating (DTR), optimal transmission switching (OTS), and demand response (DR) have proven to enhance grid flexibility and reliability. DTR is used to improve system reliability by increasing the transfer capability of transmission lines, OTS exploits the transmission line's inherent flexibility by switching some lines from the network, and DR allows consumers to efficiently utilize their electricity consumption by shifting load from peak hours to non-peak hours. This paper provides a state-of-the-art overview of the reliability impacts of ESS combined with these cost-effective tech-nologies. The emphasis is on analyzing how the coordination of ESS with these cost-effective technologies im-pacts system reliability. Firstly, a brief overview of ESS technologies and applications is provided, followed by an explanation of power system reliability evaluation methods. Secondly, the combination of ESS with each of these technologies is explored from both operational and reliability perspectives. For each coordination scheme, a general framework for evaluating reliability is presented, followed by a detailed review of the literature that discusses its impact on the reliability of the composite system Furthermore, the role of cyber layer modeling in ensuring the reliability and security of the power system when integrated with these technologies is briefly discussed.