Energy Storage and Wind Power
This page addresses energy storage and how storing energy relates to wind energy as a variable resource on the electricity grid.
"Energy storage technologies are not an alternative to any particular resource decision; rather, they are a valuable adjunct to all resources, and they will allow increased capacity to be derived from any given quantity of physical resources."
Source: Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid, a report by the Electricity Advisory Committee, December 2008.
Energy storage will best be used as a resource for the overall power system. It is not cost effective or efficient to couple energy storage resources exclusively to individual wind plants. It is the net system load that needs to be balanced, not an individual load or generation source in isolation. Attempting to balance an individual load or generation source is a suboptimal solution to the power system balancing needs. Hydropower and energy storage capacity are valuable resources that should be used to balance the system, not just the wind capacity. During this present stage of wind power integration and growth, wind simply adds to the existing opportunities for energy storage.
Is Energy Storage Needed?
At present levels of wind penetration on the electrical grid, storage has not been a priority consideration. But eventually, as a system resource and not exclusively due to wind or other renewable resource capacity additions, the nation's electrical grid will benefit from energy storage technologies. Essentially, the power system already has storage in the form of hydroelectric reservoirs, gas pipelines, gas storage facilities, and coal piles that can provide energy when needed. Read more about how power is balanced on the electricity grid. Today, storing electricity is more expensive than using dispatchable generation. In the future, through advances in technologies such as batteries and compressed air, energy storage may become more cost-attractive. The prospect of plug-in hybrid electric vehicles holds great promise because they could provide many megawatts of storage for the overall electrical power system. This would also allow wind power and other renewable energy resources to directly displace consumption of transportation-related foreign oil. Energy storage will best be used as a resource for the overall power system.
This conceptual graphic is meant to show how energy storage and other operational options compare in terms of cost tiers, from both the supply and user (i.e., demand side, consumer, or load) sides, as the penetration of renewable energy resources increases. View a larger version.
Source: Paul Denholm, NREL, The Role of Energy Storage in the Modern Low-Carbon Grid, June 12, 2008.
More Information
MISO Energy Storage Workshop Proceedings (June 29, 2011). Midwest Independent Transmission System Operator, Inc., MISO. Utility-related energy storage information likely of interest to the expert as well as the novice.
Electricity Energy Storage Technology Options: A White Paper Primer on Applications, Costs, and Benefits (December 23, 2010). Electric Power Research Institute, EPRI. The Electric Power Research Institute (EPRI) has published a comprehensive analysis of energy storage applications and technology options that also assesses the potential benefits and markets for energy storage in the United States. The analysis looks at 10 energy storage applications that EPRI considers would serve the bulk of the energy storage market and includes applications to support wholesale energy services and renewable integration. The research also identified and modeled 21 benefits of energy storage, including power quality, power reliability, retail time-of-use energy charges, and retail demand charges, among others. The analysis compared the present value of benefits with the estimated costs for energy storage systems installed in various regions across the United States.
Energy Storage for the Electricity Grid: Benefits and Market Potential Assessment Guide. (February 2010). Eyer, J.; Corey, G.
The Role of Energy Storage with Renewable Electricity Generation. (January 2010). Denholm, P.; Ela, E.; Kirby, B.; Milligan, M.
Modeling the Benefits of Storage Technologies to Wind Power (June 2008). Sullivan, P.; Short, W.; Blair, N.
Accommodating Wind's Natural Behavior DeMeo, E.; Jordan, G.A.; Kalich, C.; King, J.; Milligan, M.R.; Murley, C.; Oakleaf, B.; Schuerger, M. IEEE Power & Energy Magazine; November/December 2007; pp. 59-67.
