Congestion-induced wind curtailment mitigation using energy storage

Allowing the connection of additional renewable energy sources (RES) in areas with limited transmission capacity is becoming of a serious concern. Building new transmission lines only provides a long-term solution to cope with this issue due to the fact that it takes much longer time (up to 5-10 years) compared to time needed to build new wind farms (about 1 year). Storage is proven to be an effective solution to make maximal use of existing grid infrastructures in the short-term. This paper proposes a cost-benefit optimization formulation for optimally sizing the storage in a wind-storage system which is connected to an external spot market via limited transmission lines. A small test system is studied in order to find the optimal size of storage to avoid congestion by allowing revenue to be generated only via reducing the congestion-induced wind curtailment. Additional revenue streams can be also included to maximize the monetary value of the wind-storage system.