Energy
prices and environmental concerns are driving the United States to rethink its energy
mix and to develop domestic sources of clean, renewable energy.
Our nation
possesses abundant resources to create electricity from the wind, and the U.S.
Department of Energy (DOE) is working toward generating 20% of the nation’s
electricity supply from wind power by 2030. To help make this vision a reality,
the DOE recently awarded six projects to help develop next generation wind
turbines and accelerate the deployment of advanced turbines for offshore wind
energy in the United States.
Advanced
Magnet Lab, Palm Bay, Fla., is leading one of these projects to
develop the first fully superconducting direct-drive generator for large wind
turbines with the goal of significantly reducing the cost of wind energy. DOE’s
Argonne National Laboratory is one of Advanced Magnet Lab’s partners in this
project.
“Direct-drive
generators eliminate the need for a gearbox, which reduces weight, eliminates
moving parts, and reduces maintenance costs,” says Jerry Nolen, an Argonne
Distinguished Fellow and collaborator on the project. “Turbines based on
superconducting technology will have a huge impact on how future electricity is
generated by reducing costs and increasing reliability and efficiency.”
Wind
turbines work like a fan, but in reverse. Instead of using electricity to spin
blades to create wind, they use wind to spin the blades to create electricity.
Drive trains convert the blades’ energy into electricity.
This early
research and development project will focus on using superconducting wires,
which have essentially zero electrical resistance, allowing for greater
electricity flow and making generators smaller and lighter for their given
output. Since superconductors operate at cryogenic temperatures, cooling is
important to the system’s architecture.
The
project will also feature a direct-drive generator to eliminate the massive
gearbox, typically the component with the highest maintenance costs in conventional
wind turbines. Since gearbox size increases rapidly with turbine power rating,
it also limits the size of windmills.
“Argonne
is an excellent partner and has extensive expertise and experience in
superconductivity, the design of cryogenic systems and modeling tools for
large-scale simulations, which will be key in helping us optimize our
design,” says Vernon Prince at Advanced Magnet Lab. “The economic
viability of large turbines requires a significant reduction of the size and
weight of the drive train, which can be achieved through the use of
superconductors and a very robust turbine structure.”
Advances in drive-train technologies and configurations will help the United States
remain a global leader in wind energy and reduce its future cost. Success could
also lead to new planning, construction and manufacturing jobs in the renewable
energy market.
