Engineers at the University of Hong Kong and a private renewable energy company have developed a new micro wind turbine that can generate electricity even if wind speeds are as low as two meters per second.
Lucien Gambarota , the main inventor of the technology, says this is its advantage over conventional small wind turbines, which only work about 40 percent of the time because of low wind speed.

“We never stop this machine and they never stop because there is always one meter per second wind - 365 days, 24 hours a day, they keep working,” said Gambarota. “They deliver different levels of energy because the wind changes but these turbines they keep moving, they keep spinning.”

Gambarota says the small turbines are ideal for crowded cities such as Hong Kong because they can be installed on rooftops and balconies.

Their design is simple: plastic gearwheels, each about 25 centimeters in diameter, are linked to one another and turn, moved by the wind. Groups of gearwheels can be arranged in an array of shapes and sizes, ranging from about two up to thousands of square meters, depending on how much energy is needed and how much space is available. The energy generated by the turbines is stored in a battery, which then powers electrical appliances.

“Let’s say if you have good conditions, five, six meters per second, if you are a family with one kid you need most probably three, four square meters of that then you can most probably cover at least 60, 70 percent of your energy needs.”

The technology can also help power bigger buildings. Administrators at Hong Kong’s Sea School, a secondary school offering basic seaman training, will install the new micro wind-turbines on its roof in April.

High-resolution image of the serial turbines here: http://www.hku.hk/shareimg/upload/news_5535_picture1.jpg