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Eastern Wind Integration and Transmission Study

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Eastern Wind Integration and Transmission Study Final Report

January 20, 2010

The total installed capacity of wind generation in the United States surpassed 25 gigawatts (GW) at the end of 2008. Despite the global financial crisis, another 4.5 GW was installed in the first half of 2009. Because many states already have mandates in place for renewable energy penetration, significant growth is projected for the foreseeable future.

In July 2008, the U.S. Department of Energy (DOE) published the findings of a year-long assessment of the costs, challenges, impacts and benefits of wind generation providing 20% of the electrical energy consumed in the United States by 2030. Developed through the collaborative efforts of a wide-ranging cross section of key stakeholders, that final report (referred to here as the 20% Report) takes a broad view of the electric power and wind energy industries. The 20% Report evaluates the requirements and outcomes in the areas of technology, manufacturing, transmission and integration, environmental impacts, and markets that would be necessary for reaching the 20% by 2030 target.

The 20% Report states that although significant costs, challenges, and impacts are associated with a 20% wind scenario, substantial benefits can be shown to overcome the costs. In other key findings, the report concludes that such a scenario is unlikely to be realized with a business-as-usual approach, and that a major national commitment to clean, domestic energy sources with desirable environmental attributes would be required.

The growth of domestic wind generation over the past decade has sharpened the focus on two questions: Can the electrical grid accommodate very high amounts of wind energy without jeopardizing security or degrading reliability? And, given that the nation's current transmission infrastructure is already constraining further development of wind generation in some regions, how could significantly larger amounts of wind energy be developed? The answers to these questions could hold the keys to determining how much of a role wind generation can play in the U.S. electrical energy supply mix.

DOE commissioned the Eastern Wind Integration and Transmission Study (EWITS) (PDF 17.8 MB) Download Adobe Reader through its National Renewable Energy Laboratory (NREL). The investigation, which began in 2007, was the first of its kind in terms of scope, scale, and process. The study was designed to answer questions posed by a variety of stakeholders about a range of important and contemporary technical issues related to a 20% wind scenario for the large portion of the electric load (demand for energy) that resides in the Eastern Interconnection. The Eastern Interconnection is one of the three synchronous grids covering the lower 48 U.S. states. It extends roughly from the western borders of the Plains states through to the Atlantic coast, excluding most of the state of Texas.

The Eastern Wind Integration and Transmission Study is one of three current studies designed to model and analyze wind penetrations on a large scale.

The Eastern Wind Integration and Transmission Study was the first of its kind in terms of scope, scale, and process. Initiated in 2007, the study was designed to examine the operational impact of up to 20% to 30% wind energy penetration on the bulk power system in the Eastern Interconnection of the United States.