Optimal energy storage sizing based on wind curtailment reduction

The rapid growth in the integration of renewable energy sources (RES) such as wind and solar, promoted by environmental and economic (environmic) incentives, can lead to the current/voltage congestion problem when the distribution lines/cables can no longer accommodate the produced (green) power. This is a substantial challenges for distribution system operators (DSOs). For this problem, curtailing the excessive wind power, and/or expanding the capacity of the distribution lines/cables are possible (but not preferred) solutions. In an active network management scheme, energy storage can be effectively used as a short-term solution for the congestion management. This paper proposes an optimization formulation to assess the techno-economic possibility of employing storage, from DSO point of view, such that the amount of wind curtailment is minimized, and the congestion is avoided. A realistic test system is used with measured load and wind profile data across a year. The calculated optimal storage sizes and the corresponding net present values (NPVs) are compared with “do nothing” scenario in which the the excessive wind power is simply curtailed to alleviate the congestion.