The optimal operation of energy storage in a wind power curtailment scheme

Generator curtailment allows Distribution Network Operators to increase the maximum capacity of distributed renewable generation connections to their networks, but curtailment means lost revenue for generators. Energy Storage Systems (ESS) can mitigate curtailment by time-shifting generation away from congested periods and can combine this with other tasks. This paper develops a linear-programming optimization to maximize the revenue generated by an ESS connected to a wind farm in a curtailment scheme. The storage is used for curtailment reduction and price-arbitrage in an external market. A case study is developed and the optimization applied for storage devices with a range of efficiencies and penetrations. The effect of storage efficiency on revenue is shown to be stronger in price arbitrage than in generation-curtailment. An economic analysis is carried out for a Sodium Sulphur battery store and it is clear that, at current costs, more valuable revenue streams are required to achieve economic viability.