Optimum electricity purchase scheduling for aggregator storage in a reliability framework for rural distribution networks

•Developing a segment based energy storage scheduling strategy to reduce aggregator energy purchase cost, considering a minimum EES state of charge provision for islanding operation support.•Establishing a reliability evaluation framework suitable for large scale networks to treat the network in different ways in order to simplify the reliability evaluation in presence of EES and PV resources.•Using data clustering technique to take hourly data of load, PV, and EES in reliability evaluation. In this way the seasonal impact on load and PV generation are considered in the evaluation.

The inclusion of Renewable Energy Resources (RER) and Electric Energy Storage (EES) can significantly improve the reliability of rural feeder customers with no cross connect switches to alternative supply. In such setups, there can be a financial incentive for aggregators to facilitate bulk storage to deal electricity with energy supplier and customers by using optimal scheduling strategy. Within this context, this paper proposes a framework for network reliability assessment to include bulk storage scheduling strategy in the evaluation. In this technique, seasonal effects on load demand and RER output, electricity market price, islanding provisions and EES state of charge (SOC) are taken into consideration. Finally, a case study is presented to illustrate the application of this approach and to evaluate the results.