Optimal power flow analysis of energy storage for congestion relief, emissions reduction, and cost savings

AC optimal power flow (OPF) simulations are used to study the effects of large-scale energy storage systems on a power system. The economic effects are analyzed under several different conditions, and CO₂ emission reductions offered by the use of storage are considered. The modified IEEE 25-bus Reliability Test System with energy storage and solar photovoltaic generation is simulated using commercial OPF software. The total fuel and emissions costs, and the cost of renewable energy, are analyzed. The net cost savings and unit cost savings provided by energy storage are presented as an economic estimate for constructing an energy storage system. Congestion relief appears to be an economically-promising application for currently-available energy storage systems.