PNNL - 23390

This report supplements the report, "Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems," PNNL-22010, Rev. 1, June 2014. It provides the background and documentation associated with the determination of a duty cycle to be applied to an energy storage system (ESS) in a microgrid operated in an islanded mode, for the purpose of measuring and expressing ESS performance in accordance with the June 2014 protocol for measuring and expressing ESS performance.