Sizing of energy storage for power systems with wind farms based on reliability cost and wroth analysis

Wind power has emerged as a promising and feasible resource to provide clean energy. The intermittent and uncontrollable characteristics of wind power yet create many stability and reliability issues in power system planning and operation. Battery energy storage systems (BESSs) have been broadly used to solve the problems. Reliability cost and worth aspect of an ESS is not considered in most studies. This paper proposes an analytical technique to size BESSs for power systems with wind farms based on reliability cost and worth analysis. The expected energy not supplied (EENS) and expected energy not used (EENU) are used to evaluate reliability cost and worth. The proposed technique is applied to the IEEE-RTS with a 500MW wind farm. Useful information is obtained for the system planners and wind farm owners to make expansion and improvement decision of the power system.