Managing large scale energy storage units to mitigate high wind penetration challenges

Due to its intermittent nature, high wind penetration requires more flexibility in the electric power grid to provide the balance. Large scale energy storage is one such option that allows the intermittency to be absorbed in real time. Two types of large scale energy storage technologies including Sodium Sulphur (NaS) battery and compressed air energy storage (CAES) are studied in this paper. In this paper CAES is modeled and evaluated as a large-scale mechanical energy storage unit highlighting its various operational characteristics. This paper focuses on how to maximize the wind energy penetration level while satisfying all the system constraints including wind spill energy constraint and power balance equations. This problem is solved considering different combinations of CAES and NaS battery scenarios. The problem is formulated as a mixed integer linear programming (MILP) solved by CPLEX. To showcase the applicability of the proposed approach, a simulation case study based on a real-world 15-minute interval wind data from Bonneville Power Administration (BPA) in 2013 is presented.