The operations and planning rules for integrating variable resources aren’t the same across the electric power industry in the United States at present. Opinions are somewhat divided about what...
The intelligent grid cannot be achieved without energy storage.
Reduced CO 2 and NO x emissions achieved by the avoidance of ramping thermal plants up and down to provide ancillary services.
Recent developments by leading storage equipment manufacturers, delineated below, indicate their belief that utilities and others in the electricity sector are becoming more receptive to using Li-ion batteries as a grid-stabilization tool.
• A123Systems installs inaugural Hybrid Ancillary Power Unit (H-APU). A123Systems—a developer and manufacturer of advanced nanophosphate Li-ion battery systems—deployed its initial commercial unit at a Southern California power plant owned by AES Corp. in mid-November. A123 claims that the system is capable of delivering 2 MW of power at close to 90-percent efficiency. The H-APU unit will be used primarily to support variable RE resources, as well as provide frequency regulation services. Looking ahead, A123 is under contract to deliver several additional H-APUs in 2009 for use in grid-stabilization applications at other AES facilities.
• Altairnano receives green light to commercially operate advanced lithium-titanate battery system in PJM Interconnection control area. Intended to provide grid-regulation services, Altairnano’s 1-MW, 250-kWh system is the first of its kind to receive approval for use in one of the largest electricity markets in the United States. The product of a joint development agreement between Altairnano (based in Reno, Nevada) and AES, the system can provide on-demand power for 15 minutes of frequency regulation and has a 90- percent cycling capability. Altairnano reports that it is in negotiations on a number of future projects that encompass frequency regulation, photovoltaic (PV) smoothing, and wind-energy mitigation applications.
• Saft and ABB unveil jointly developed high-voltage Li-ion battery system designed to manage short-term load or supply variations and enhance overall distribution grid stability. The new system, which was unveiled in late November, combines Saft’s 5.2-kV battery with ABB’s SVC (Static Var Compensation) Light technology, providing the dual ability to respond to grid disruptions and perform dynamic voltage control. The system reportedly can deliver 200-kW for an hour and 600-kW for over 15 minutes. Meanwhile, in combination with dynamic energy storage, an 11-kV pilot system can deliver 600-kVAr reactive power and 600-kW active power. The companies plan to field test a unit in 2009 at an undisclosed location with an eye toward installing full-scale commercial systems in 2011.
Additionally, utilities continue investing in storage systems using other battery technologies. For example, Xcel Energy is installing a 1-MW NaS battery from NGK Insulators to directly store up to 7.2 MWh of wind energy and then transfer it to the grid when needed. The system is being installed in Luverne, Minnesota, just south of the wind-rich Buffalo Ridge area. The NaS system will be adjacent, and connected to, an 11-MW wind farm owned by Minwind Energy LLC.
The project, which also involves the University of Minnesota, the National Renewable Energy Laboratory, and the Great Plains Institute, will be a test-bed for using storage to better coordinate the output from variable wind-generation facilities with transmission availability and energy demand. And, according to Xcel, this is the first U.S. application of an NaS battery as a direct wind-energy storage device. (American