The benefits provided by energy storage appear to be nearly limitless and this is especially true in regards to power systems. Gas turbine generators are needed to meet peak load demand but operating them is quite expensive. Energy storage can be used to flatten the electrical load by charging the storage when the system load is low and discharging the storage when the system load is high. If the system load is flat enough, the fast response time of gas turbine generators won't be needed. This study investigates the economic feasibility of NaS battery storage and pumped hydro energy storage used for the application of load leveling.