Abstract
Battery energy storage systems (BESS), demand response (DR) and the dynamic thermal rating (DTR) system have increasingly played important roles in power grids worldwide. In addition to storing energy, BESS can supply peak demands, thereby reducing the frequency of load interruptions and deferring new asset investments. However, study on the precise BESS sizing (i.e. energy and power ratings) to supply peak demands to improve the security of supply of transmission networks is still lacking. The combined efficacy of BESS, DR and DTR have also never been studied, because their simultaneous deployment has never been considered. The first contribution of this paper is proposing a probabilistic evaluation method to evaluate various combinations of BESS power ratings and energy capacities and determines their impacts on the reliability of transmission networks, in which peak demands are supported by charges stored in BESSs to address the security of supply problem. The second contribution extends the proposed method to examine the effects of deploying BESS alongside DR and DTR. Our results show that the security of power supply improves along with BESS sizing by as much as 37.2%, and that its reliability becomes more significant as its capability grows, with bigger BESS having more detrimental effects towards EENS as it becomes unavailable than smaller BESS does. DTR and DR reduce the requirements of BESS sizing without adversely affecting network reliability.