U.S. Department of Energy Wind Energy Research Program for Low Wind Speed Technology of the Future Stan Calvert U.S. Department of Energy, 1000 Independence Ave. S.W., Washington, DC 20585-0121 e-mail: stanley.calvert@ee.doe.gov Robert Thresher, Susan Hock, Alan Laxson, and Brian Smith National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401-3393 National Energy Policy Priorities The United States is facing many challenges as it prepares to meet its energy needs during the twenty-first century. Electricity supply crises in California, fluctuating natural gas and gasoline prices, heightened concerns about the security of the domestic energy infrastructure and of foreign sources of supply, and uncer- tainties about the benefits of restructuring are all elements of the energy policy challenge. In May 2001, the President’s National Energy Policy Develop- ment Group released a set of recommendations that have become the cornerstone of U.S. Energy Policy under the George W. Bush Administration @1#. Pursuant to the release of the National Energy Policy recommendations, Secretary of Energy, Spencer Abraham, described the three priorities of the Department of Energy as: • Ensuring energy security by strengthening the energy produc- tion and delivery infrastructure • Focusing on programs that increase the supply of domesti- cally produced energy, and that revolutionize how the country approaches conservation and energy efficiency • Directing research and development ~R&D! budgets on ideas and innovations that are relatively immature and ensuring the greater application of mature technologies The Assistant Secretary of Energy Efficiency and Renewable En- ergy, David Garman, stated that implementation of the Secretary’s priorities will involve nine elements @2#, including: • Reducing dependence on foreign oil • Reducing the burden of energy prices on the disadvantaged • Increasing the efficiency of buildings and appliances • Reducing the energy intensity of industry • Creating a domestic biomass industry Most relevant to the Wind Energy Research Program is the prior- ity to: ‘‘Increase the viability and deployment of renewable energy, by developing a diverse portfolio of renewable energy technologies that reduce the average cost of renewable energy production by 20% by 2010 and achieving cost-competitive parity with the av- erage cost of energy by 2020.’’ Current Market Situation and Potential Opportunities Competitive cost of energy ~COE! levels have been achieved by focusing development on Class 6 wind resource sites ~average wind speeds of 6.4 m/s @10-m height! and by taking advantage of the production tax credit ~1.7 ¢/kWh in 2002 $!. With favorable financial terms, Class 6 sites can market electricity at prices of 4 ¢/kWh or less before the subsidy. However, as more sites are developed, easily accessible prime Class 6 sites are disappearing. In addition, many Class 6 sites are located in remote areas that do not have easy access to transmission lines. The full development of accessible Class 6 sites may cause wind energy growth to pla- teau in the near future unless improvements in technology can make lower wind speed sites more cost effective. Class 4 wind sites ~5.8 m/s @10 m! cover vast areas of the Great Plains from central and northern Texas to the Canadian border. Class 4 winds sweep across the majority of North and South Dakota. Class 4 sites are also found along many coastal areas and along the shores of the Great Lakes. While the average distance of Class 6 sites from major load centers is 500 miles, Class 4 sites are significantly closer, with an average distance of 100 miles from load centers. Thus, utility access to Class 4 sites is more attractive and less costly. More importantly, Class 4 sites represent almost 20 times more developable wind resource than Class 6 sites. Figure 1 shows regions with Class 4 and greater resources. Currently wind energy at Class 4 sites can be marketed at prices in the range of 5– 6 ¢/kWh. Advanced low wind speed technology will be required for wind technology to be cost-competitive at Class 4 sites. Low Wind Speed Technology Goal. The program has de- fined goals for its technology development activities that will po- sition wind as an attractive advanced technology option for the twenty-first century. The low wind speed technology ~LWST! goal is to reduce cost of energy from large wind systems to 3 ¢/kWh in Class 6 wind resources by 2004, and to 3 ¢/kWh in Class 4 wind resources by 2010 ~compared to a 2002 baseline of 4 ¢/kWh in Class 6 and 5.5 ¢/kWh in Class 4!. Capacity Addition Benefits of Low Wind Speed Technology. DOE researchers have developed an estimate of the additional capacity that could be installed in the U.S. as a result of the development of LWST. Their projections were developed using the National Energy Modeling System ~NEMS!, DOE’s primary electricity sector modeling tool. Assuming a turbine capable of producing electricity for 3 ¢/kWh in Class 4 sites became avail- able in 2010, the NEMS projected wind capacity in 2020 would be about 50 GW or 40 GW above the baseline expectation, which represents a significant benefit to the nation. This projection as-