Benefits of Grid-Connected Battery Energy Storage Systems for Reliability Enhancement

Battery energy storage systems (BESSs) are a promising solution for mitigating power system components outages. While installing BESSs to mitigate outages and defer network upgrades, the asset owners can also seek to provide additional services, such as frequency regulation, to accelerate the payback of the BESSs investment. Existing work barely discusses the commitment failure risks due to the service stacking, not to mention the BESS operational constraints and optimal sizing. This paper proposes a stochastic computation framework to assess the benefits of BESSs for reliability enhancement by performing outage mitigation and frequency regulation, also the commitment failure risks due to service stacking. The computation framework is implemented on the IEEE RTS-96 with frequency data from the Great Britain grid. Results show the annual revenue of £1.07M from reduced load interruption and frequency regulation by using a 10 MW, 20 MWh BESS, compared to £0.52M from only providing reduced load interruption.