10MW superconductor wind turbines to be studied

American Superconductor Corporation (AMSC) announced that it has entered into a Cooperative Research and Development Agreement (CRADA) with the U.S. Department of EnergyÂ’s National Renewable Energy Laboratory (NREL) and its National Wind Technology Center (NWTC) to validate the economics of a full 10 megawatt (MW) class superconductor wind turbine.

AMSC is separately developing full 10 MW-class wind turbine component and system designs. A CRADA allows the Federal government and industry partners to optimize their resources, share technical expertise in a protected environment and speed the commercialization of technologies.

Under the 12-month program, AMSC Windtec, a wholly owned subsidiary of AMSC, will analyze the cost of a full 10 MW-class superconductor wind turbine, which will include a direct drive superconductor generator and all other components, including the blades, hub, power electronics, nacelle, tower and controls. The NWTC will then benchmark and evaluate the wind turbineÂ’s economic impact, both in terms of its initial cost and its overall cost of energy.

“The Department of Energy and its National Renewable Energy Lab recognize that wind power will represent a significant fraction of our power production in the years to come,” said NREL Director Dan Arvizu. “High temperature superconductors hold promise for helping lower the overall cost of wind energy. We are pleased to be teaming with AMSC to move this technology forward.”

Direct drive wind generator systems utilizing high temperature superconductor (HTS) wire instead of copper wire for the generatorÂ’s rotor are expected to be much smaller, lighter, more efficient and more reliable than conventional generators and gearboxes. AMSC estimates that its superconductor technology will enable a 10 MW-class generator system that would weigh approximately 120 metric tons, compared with approximately 300 metric tons for conventional direct drive generators with this power rating.

In addition, direct drive generators eliminate the need for massive gearboxes, the component with the highest maintenance costs in conventional wind turbines. This will open up the opportunity for the development of wind farms in more areas on land and offshore.

The superconductor generators that are to be utilized for 10 MW-class superconductor wind turbines are based on proven technology AMSC has developed for superconductor ship propulsion motors and generators under contracts with the U.S. Navy. AMSC recently announced that a 36.5 MW superconductor ship propulsion motor it designed and manufactured for the Navy was successfully operated at full power by the Navy and is ready for deployment.

Concurrent with the CRADA, AMSC and TECO-Westinghouse Motor Company (TWMC) have been working on a project since October 2007 to develop HTS and related technologies for 10 megawatt-class direct drive wind generators under an award from the National Institute of Science and TechnologyÂ’s Advanced Technology Program (ATP).

The CRADA and ATP programs are intended to serve as a prelude to follow-on programs aimed at building and testing a full-scale prototype superconductor wind turbine, prior to commercialization.

Senior Vice President and AMSC Superconductors General Manager Dan McGahn said, “It is important for our economy to embrace new clean technologies that will increase our energy independence and strengthen our electricity infrastructure. Superconductors are today proving their tremendous power density and efficiency advantages to electric utilities and large power users. This program brings those same benefits to power generation and the rapidly growing wind power market.”

Wind turbine power ratings have been increasing steadily while the price per megawatt has declined, enabling wind power to achieve economic parity with conventional generation sources in prime wind locations. Due to the limitations of conventional technologies, however, the largest wind turbine ratings top out at approximately 6 MW due in part to practical limitations on the physical size and weight of the generators that must be transported over roads and supported on towers hundreds of feet in the air.

“HTS is one of the ‘disruptive technologies’ needed to break through wind power’s capacity barrier and significantly reduce its cost of energy,” McGahn said. “We have formed strong ties with wind turbine manufacturers around the world, including TECO in Taiwan, Sinovel Wind in China and Hyundai Heavy Industries in Korea. Based on these relationships, AMSC’s leadership in superconductor technology, its experience with HTS rotating machines and AMSC Windtec’s proven commercial wind turbine design capabilities, we are uniquely equipped to commercialize this breakthrough technology.”

According to industry research firm Emerging Energy Research, approximately $27 billion was spent on wind turbines in 2007. That figure is expected to double to over $55 billion annually by 2015.