Small wind - is it worth the price?

I'm a member of the small-wind-home@yahoogroups.com . This a group of people interested in Small wind. Someone posted this article from Low Tech magazine. Redriven the turbine that I'm waiting to install was not in the study. Of coarse the small wind group found many things wrong with the study.

http://www.lowtechmagazine.com/2009/04/small-windmills-test-results.html As you can see from this looking at the test, their towers were not tall enough. The turbines should tower over the trees like the radio tower in the picture.

One of the conclusions of this article is that large scale turbines are more efficient. Would anyone disagree? But what they are missing is that these small wind turbines will help promote wind. They will prove to people that wind generators are not the evil noise machines that the anti wind people would have everyone believe.


I considered going big - getting a lot of neighbors or investors to get a very large wind turbine. I've seen how much work it is to get permits to do that kind of project. There was an attempt to do a wind farm near where I live. There was a huge out cry from the community that ended with a ban on all large scale wind farms project. Maybe my small project will show them that wind turbines are not so bad. Then when a neighbor tries to get a permit to go a little bigger there will not be the backlash. Some day we might get those more efficient models in our hood.

We could invest in wind farm stock, but we all know how much fun the stock market is these days.

Reports of issues with the Redriven 20KW Turbines blades

It seems there are a few reports of Redriven 20KW wind turbines breaking off blades during high winds and a few others that almost had the same fate. (See the comment left on my April 4 entry).

Here is what I’ve found:

Back in February, there was a report of a high school with three Redriven turbines that had blades hit the pole and flew off. See this link for more details

http://www.wind-watch.org/news/2009/02/10/blade-breaks-off-wind-turbine/

Here is an account of several more having the same issue.

http://www.windaction.org/news/20716

I contacted Scott Jackson who wrote the report. He said that the 10KW are not having the same issues with the blades breaking up but have had controller issues.

He gave me the name of someone with the 10KW in his back yard. He said this person could tell me about the controller issue first hand. I called him and he said that he did have controller issues, but Redriven took care of the problem by providing a retro fit. They added a resistive load. He has not had the problems since the retrofit. He's not worried about the blade issue and is now thinking of getting a 20KW with a tilt up tower. ( I didn't know 20KW could tilt up). He would then move his 10KW to another site. He said that he can see many wind turbines from his property. During a recent storm, many of turbines in the view from his home lost blades. He hasn’t lost a blade yet.


I also found this article about how Redriven is fixing the issues at Perkins High School.

http://www.morningjournal.com/articles/2009/04/18/news/mj913904.txt

This article says that Redriven is replacing the blades at Perkins High School with an older technology blade and is monitoring now for vibrations.

I would love to hear more from people with first hand experiences with Redriven. Please contact me or post your comments.

*******Update *** 5-30-09 here is another artical on this topic ******

http://www.agrinewsinteractive.com/fullstory.htm?ArticleID=10072&ShowSection=News


******Update ****10-03-09 I found more info on the Perkins School . Here is a news letter tell more details about testing and new blades.
http://www.perkins.k12.oh.us/pages/uploaded_files/Perkins%20United%20Fall%202009%20for%20web.pdf

also a news paper article
http://www.sanduskyregister.com/articles/2009/08/31/front/1582172.txt


UPDATE - May 2010 ****see what Redriven says about new designs

Is the Redriven's Wind Generator the right choice for a home owner?

UPDATE : 12/21/10 -  Redriven no longer gets their turbines from the SWG - Yangzhou Shenzhou  Company.  More than a year ago they started making their own parts in China. Redriven has their own factory in China run by Cameron Grant.  None of the parts of my turbine are manufactured by  SWG - Yangzhou Shenzhou  Company.

Paul Gipe is THE authority on Wind power. In his book, Wind Power, he says “ Rotor diameter says it all”. What you are looking for is energy not power. Your ability to capture the wind’s energy is what is important. Of course hub height is also important. The trade off with hub height is the ability to service the turbine. We settled for 80ft in order to get the ability for a hydraulic tilt up tower.

Gipe also says that the power curves given by manufactures are just “informed guess work” and should be viewed with “ a good dose of skepticism.”

The power curve is made up of:

Star-up Speed (starts turning)
Cut-in Speed (start producing power)
Rated speed (speed that it reaches is rated power)
Peak power (Max power it can produce)
Cut-out speed (Speed that the generator stop producing power and go into protection mode)
Furling Speed (For turbines with tail vanes)
Wind Speed Bin (A way to produce discrete data from continuous data)

The Redriven Turbine’s published data in this area is superior to other 10KW turbines. Longer blade diameter, low start up wind speed the ability extend the peak power with the active yaw points to a better performing wind turbine.

However! Another big consideration is reliability. Everyone expects to get many years out of a wind turbine. This is my biggest concern in picking the Redriven product. It is very new and doesn’t have a proven track record of performance. If the product has many issues, will Redriven and my installer be able to be able to keep the installed based operational and be profitable during the five year warrantee period. Will we be able to get parts to keep the turbine working long enough to get our investment back?

I started my investigation trying to find out about the Chinese company that make Redriven’s turbine. I did a search with the terms Redriven and China and came up with shipping documents http://www.importgenius.com/importers/redriven.html
Yangzhou Shenzhou shipping to Redriven in Canada.

As soon as you go to the SWG - Yangzhou Shenzhou web site it is clear that is the Redriven product. Same look, same tower, same hydraulic lifting mechanism.
http://www.f-n.cn/


I did some investigation on the Internet and found that Redriven’s supplier is SWG - Yangzhou Shenzhou. They have been in business for 12 years. ISO 9000 certified.

One of the best sites for seeing the product that the Chinese manufacturer sells that I have found is http://www.evolvegreen.ca/catalog/item/6319999/6614526.htm
They have many manufacture PDFs

http://shenzhougenerator.en.alibaba.com/
also shows the wind turbines.