Minimizing Unserved Energy Using Heterogeneous Storage Units

This paper considers the optimal dispatch of energy-constrained heterogeneous storage units to maximize security of supply. A policy, requiring no knowledge of the future, is presented and shown to minimize unserved energy during supply-shortfall events, regardless of the supply and demand profiles. It is accompanied by a graphical means to rapidly determine unavoidable energy shortfalls, which can then be used to compare different device fleets. The policy is well suited for use within the framework of system adequacy assessment; for this purpose, a discrete time optimal policy is conceived, in both analytic and algorithmic forms, such that these results can be applied to discrete time systems and simulation studies. This is exemplified via a generation adequacy study of the British system.