Maglev wind turbine

A Maglev wind turbine or Maglev windmill would use magnetic levitation to replace conventional bearings in the design of a wind turbine. A recent design was developed in China by Guangzhou Energy Research Institute under China’s Academy of Sciences and by Guangzhou Zhongke Hengyuan Energy Science & Technology Co., Ltd.

The design claims to utilize winds with starting speeds as low as 1.5 meters per second (m/s), and cut-in speeds of 3 m/s. This could add 1,000 hours of operation annually to wind power plants in areas with an average wind speed of 3 m/s. However, since the energy available in wind varies as the third power of wind speed, the power produced at such velocities would be lower than conventional wind turbines under higher speed winds.

The rotating turbine shaft is supported by magnetic levitation instead of ball bearings. Magnetic bearings have been used for smaller turbines and pumps, but they generally can't handle impacts disturbing the shaft, and generally require actively controlled electromagnets. Making magnetic bearings strong enough to handle the loads of a wind turbine would use prohibitive amounts of power just keeping the electromagnets running. The Chinese design is said to use permanent magnets to support the rotor shaft. Little detailed technical information supporting these claims is yet available in English.

Chinese company Zhongke Hengyuan Energy Technology invested CN¥400 million in building the base for the maglev wind turbine generators, in which construction began in November 2007. The company expects a yearly revenue of CN¥1.6 billion from the generators.

Maglev Wind Turbine Technologies Inc. announced the launch of a wind turbine power generating device based on magnetic levitation called the Maglev Wind Turbine on July 26, 2007.