Department of Energy Selects Projects to Develop High-Efficiency, Lightweight Wind Turbine Generators for Tall Wind and Offshore Applications

The U.S. Department of Energy (DOE) has selected projects to develop next-generation wind turbine drivetrain technologies that will facilitate the continued growth of wind turbines for both land-based tall wind and offshore applications. These projects will develop more efficient, smaller, and lighter-weight generators that will lower costs and make wind power more affordable. To learn more about wind turbine drivetrain technologies, see our blog.

Each of the selected projects received $500,000 to design a wind turbine generator that can be scaled up to at least 10 megawatts to capitalize on the trend of larger, more powerful wind turbines, especially for offshore applications.

One project developed a “direct drive” permanent magnet generator design that is smaller, lighter, less expensive, more reliable, more efficient, and uses less rare earth content than conventional gearbox designs.

• WEG Energy Corporation of Duluth, Georgia developed a high-efficiency permanent magnet direct drive lightweight generator to integrate into its existing platform.

Two projects developed superconducting generators, which make a much stronger magnetic field using superconducting windings. This results in a significant size and mass reduction over conventional generators and significantly reduces the need for foreign-sourced rare earth materials.

• American Superconductor Corporation of Ayer, Massachusetts developed a high-efficiency lightweight wind turbine generator that incorporates high-temperature superconductor (HTS) materials to replace permanent magnets in the generator rotor, potentially reducing size and weight by 50%. The advantage of an HTS design is the higher operating temperature of the generator windings, which significantly reduces the challenges associated with maintaining supercritical temperatures in the generator. The challenge with HTS machines is that the winding material is much more expensive, and it comes in relatively short lengths, necessitating many splices.
• General Electric (GE) Research of Niskayuna, New York developed a high-efficiency ultra-light low temperature superconducting (LTS) generator, leveraging innovations from GE’s magnetic resonance imaging (MRI) business. The generator will be tailored for offshore wind and scalable beyond 12 MW. The advantage of LTS generators is the availability of low-cost LTS wire in lengths needed to wind the generator without splices. The challenge with LTS designs is the need to cool the windings to about 4° kelvin, which typically requires the use of liquid helium.

Following the design and analysis phase, in January 2021, DOE selected GE Research to receive up to $20.3 million to build and test a scaled prototype of their generator on a wind turbine.

If successful, this project will result in a design that is up to 50% lighter while reducing the cost of wind generation by up to 10%. To learn more about how lightweight, high-efficiency generators will reduce the cost of energy from tall wind and offshore wind applications, see the EERE blog.

For more information on DOE’s efforts to lower the cost of wind energy, visit the Wind Energy Technologies Office website.

Note: This EERE Progress Alert was initially posted on May 2, 2019, and was updated July 3, 2019 and January 20, 2021.