Hong Kong Inventors Unveil New Micro-Wind Turbines Suitable for City Dwellers

Submitted by Norm Roulet on Tue, 04/24/2007 - 23:13.

Buzzing Hong Kong is better known for keeping lights on all night and the air conditioner running full blast, not saving energy. But engineers in the city have introduced an innovative wind energy technology than can help both rural and city residents protect the environment and cut down on energy costs - without having to spend a fortune on an expensive device. Claudia Blume reports.

A large wind turbine on a small outer island is one of Hong Kong's few sources of renewable energy. One of the reasons not more are being built is that the wind in the city is simply not strong enough, a problem it shares with many places worldwide.

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.

The wind turbine is easy to install and comparatively cheap. At the moment, a set of 20 gearwheels costs about $25. Gambarota says the price will go down once the turbines are being mass-produced, making them a good option for consumers who want to cut down on their energy costs.

"Let's say if you have good conditions, five, six meters [of wind] 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.

Gambarota says his biggest dream is to see his invention being used in developing countries. He says energy generated by micro wind turbines can be used to pump water, for example, saving women and girls from having to walk for miles to rivers and lakes to fetch it.

VOA News


The reason these turbines turn in a very slight wind is because they are eight bladed and each blade appears in the photo to have a very high (45 degree) pitch.  This is a high starting torque design but INHERENTLY VERY INEFFICIENT.   This design  is similar to the multi-bladed old western farm water pumping windmills  which needed a high starting torque to break the inertia in the mechanical system and get the water pump off dead center and moving .   The improvement with these plastic turbines over the very inefficient western style wind mills is that the plastic turbines are ducted – surrounded by a plastic circular shroud which improves their efficiency by confining the wind flow as discussed  in my comment to Bill MacDermott's post about Binary Building Turbines on Realneo here.


The rule in wind turbines is that the fewest number of blades allows the highest blade tip speed which equals the highest efficiency of energy extraction.  Therefore, this plastic design is way over on the least efficient end of the design spectrum.


The problem with a low number of blades (theoretically a counterweighted one bladed turbine is most efficient) is that the magnetic field in the generator “locks” the turbine rotor from starting to rotate in a slight wind.  Because the multiple field magnets and multiple armature segments demonstrate an uneven resistance to rotation called “cogging”,  the wind turbine rotor gets “caught” magnetically and requires a strong wind to break out of the magnetic “cog” and get rotating .  Once rotating, the turbine blades will continue to rotate if the wind slows down, but once stopped has to have the wind go up high to again break out of the cog. Variable pitch blades help reduce this problem (but are complex and expensive).


That the small plastic turbines will be mass produced cheaply is great, but they  could be much more efficient at the same low cost if the generator is designed with as few magnetic “cogs” as possible (more complexity) and if sophisticated electronics (including starting capacitors) are used to vary the magnetic flux (or vary the air gap)  in the generator with variations in wind speed.


Rather than spending Cuyahoga taxpayers money on the dream of “about 10” huge wind turbines in Lake Erie, the Cuyahoga County energy “task force” should fund  research and manufacturing of this type of “massively parallel processing” small wind turbines. Think of these small turbines as energy converters just as leaves on trees are photo energy converters.  Nature doesn’t put one giant leaf on a tree, but massive parallel processors – many leaves. Got a better idea than Nature?  Tell us about it…


This turbine technology could take wifi mesh off grid

You need to check out the technology at this company's site - they also are working on wave power technology - we should get them to set up some R&D here - they look interested in new business opportunities. See their website here - it has lots of energy analyses so you can get your engineer hat on and see if it makes sense... I'm ready to order some turbines for the wifi and servers at the Star Complex! Imagine a few of these at each of the wifi access points to power the mesh - an off the grid mesh - totally doable today with this technology! Talk about building a tree with many leaves.

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Hi there I saw on my website

Hi there

I saw on my website that there was some traffic from this blog so i went to check who was so nice to help us spreading the news.i want to thank Norm and also Suzan for her welcome message.

I have registered in order to answer to Jeff Buster's worries.

Jeff ,We do not have all the problems that you have mentionned,so i think that you    have  posted an answer before checking what is Motorwind technology.

This is what is interresting about internet,nothing escapes from scrutiny.

I have released Motorwind just 6 weeks ago right after having finished the last tests

in a wind tunnel at the local University and since then i came to realize what we really

did. We have created a 1 billion people market overnight .

All those who cant afford anything else ,all those who could not use anything else,all those who did not dare using anything else.

during these 5 weeks I have to create a multi national corporation doing manufacturing ,distribution,installation etc etc  starting from ZERO and with very limited ressources.

my main focus is to make Motorwind available to those who are in real need.

India-south America-Africa-remote China-thousands of islands anywhere.

The succes we are having is what makes human being still having hopes.

Very tiny companies can solve problems that the giant ones keep denying:pollution.

best regards

Lucien Gambarota


Lucien, how about making Cleveland your US headquarters

Lucien, you are doing there exactly what we want to have happen here - inventing - researching and developing - starting a rapid growth business in an explosive market - engineering - designing - manufacturing - being socially responsible. And you are growing business in a cluster important to this region, and country. So how about doing some of what you are doing and need to do here in Northeast Ohio, USA. We are a major American city in every way, with land and facilities available to suit any need, a strong manufacturing foundation, with excellent road, port and rail access to most of America's population and Canada, and an excellent workforce to fill every position - the world's best industrial designers and engineers - and a low cost of living and business. If you need government support, funding, public relations - you'll find everything easy to cover here. Let us know if you may be interested and I'll immediatley connect you with all the right development people here.

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technology transfer

Tks Norm for your support

To make this technology very efficient in every aspect i have to follow the principle

that electricity must be generated as close as possible to the user and the turbines must be manufactured also as close as possible to the end user .in that way the energic cost  needed to make these turbines + shipping  will be only a small percentage on the global balance.

at the scale of a country ,by not importing a finished product ,but rather using local labor

will easily absorb the manufacturing cost. 

By using local network of installers will stimulate the economy and all this paid by not importing oil from Middle East.

so i need absolutely to have as many manufacturing plants disseminated on the planet as possible.The only limit that i have today is financing.I am initiating Joint Ventures in as many places as possible in order to increase my financing ,manufacturing ,distribution capacity.

If you can help me on that aspect with your city/state/investors then i am extremelly interested.

i want to go fast and  your help is critical on that aspect.


best regards


P.S : it will be a "school case" in the coming years taught in universities  if we can solve problems through an internet encounter.




Making NEO a center of Micro-Turbines

There are many people dedicated to making advanced energy work here. You claim to make advanced energy work. You propose a consumer product solution requiring manufacturing, which we want here. So many synergies. I'll have people lined up to explore this in a few days. Thank you for your interest in this regon. It is very cool you are connected with us here, and we appreciate that.

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The wheels are in motion for micro wind in NEO

I talked with City of Cleveland "Tech Czar" Michael DeAloia and Cleveland Institute or Art Chair of Industrial Design Dan Cuffaro today about supporting your business here. Totally supportive. Next up are Gary Johnson, of the World Trade Center, and Tom Waltermire of TeamNEO... and the good folks at the Cleveland Foundation... so many others to be involved. I'll have a delegation of community development champions lined up to support you in a few more days - let's do it up.

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