FACTS devices with battery-based energy storage - extending the reach of traditional grid stability systems

Electric energy storage is currently gaining an increasing interest. Among the drivers are renewable energy integration and an increasing number of electricity markets are seeking services that can be provided by energy storage. One way to store electric energy is to use batteries. The paper gives an introduction to the current market movements and possibilities to meet the market needs using battery-based energy storage. Examples are given from the renewable integration and ancillary services. Safety of any energy storage system is paramount. Until today, most of the discussions have been around the choice of battery chemistry. The paper widens the view on safety and considers the entire energy storage system. Examples are given on how different faults are handled.