Windspire 1 kW Vertical Axis Wind Turbine
Mariah Power’s Windspire is a neat looking 1kW vertical axis wind turbine that provides an aesthetically pleasing wind power option. It is appropriate for rural, urban, and residential environments alike, and at 30 feet and producing only 25 db, it conforms to typical residential and urban zoning restrictions.
Windspire is a low-cost, easy-to-install wind power device that provides a safe and attractive method for harnessing power from the wind. At only 30 feet tall and 2 feet wide,the moving rotor section is a full 10 feet off the ground, well out of the way of people.
It is distinguished by its propeller-free design, silent operation, producing only about 25 dB, taken 5 feet from the base; rugged construction, simple installation and affordable pricing. Windspire spins at about the same speed as the wind. This makes it virtually silent, clearly visible, and very safe for both people and birds.
At $3,995.00 it comes complete with:- The rotor ("turbine")
- The generator
- The inverter
- The pole and pole stand
- Wiring down to ground level
- The installation kit - everything you need to install the turbine
- Owner's and Installation Manuals
- A 5-year warranty Rugged yet simple construction means durability - the Windspire is rated for winds up to 100 mph.
General
Rotor
Electrical Components
Wind Ratings
Foundation
Other
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As I understand it, this configuration usually suffers from high bearing wear in normal use and windshear can cause excessive bearing wear which is why vertical acess has never taken off.
How have the dealt with this problem?
Posted by:Green Assassin Brigade | September 10, 2007 at 10:42 AM
I've never heard of excessive bearing wear being a major problem with VAWT's. My only problem is that this turbine is fairly close to the ground and shouldn't generate a lot of power. I'd rather have a shorter turbine mounted on a taller pole.
Posted by:The Anonymous Poster | September 10, 2007 at 10:47 AM
Is there any test data or evaluations as with Turby, windside,Vestas, Aerotecture, carbon concepts, Pacwind, or solwind?
Can they post the bearing design...this is a very tall closed veined turbine; I'm guessing subject to a lot of stress in moderate winds?
How is the rotational energy delivered to a generator...belt or is the bottom of the shaft wound and turning in a magnetic field?
...o.k. I've got a few reservations about this design; and other vendors can provide a 'ruggedized' marine version for off shore/island/ship use..see windsides tech. specifications for their off-shore product series.
Posted by:fjh | September 10, 2007 at 11:37 AM
How would these work if you installed them on the sides of existing concrete posts along highways or other of millions of posts already existing, with top and bottom secured to power traffic lights, phones, cell antenas, and even supply power to the grid they support?
Also all the giant publicity signs should use wind power for lighting, they are made to withstand high winds already.
I definitely think vertical is the way to go for wind power, it solves the danger of blades cutting through the air and you can take advantage of lower wind speeds which are more the norm than high wind speeds.
Posted by:greg | September 10, 2007 at 12:07 PM
I think that * in their data needs some validation. Or we may be facing yet again some outrageous VAWT claims not backed up by physics and math.
Wind power 101 says that addressable wind power is a function of wind speed (cubed) times wind swept area.
This pole-like turbine has a wind swept area of ~40 ft (20 feet by 2 feet) or slightly less than 4 square meters.
Sorry, but no turbine on a planet with earth's air will produce 1000 or 2000 watts of electical power from such a measly wind swept area. (maybe in water... :)
Posted by:Jeremy Stieglitz | September 10, 2007 at 01:15 PM
According to NREL, class 7 wind power at 21 mph is 1kw/m^2. As a wind turbine can capture up to 50% of the energy, those numbers seem feasible. Of course the average power would be much lower.
http://www.nrel.gov/gis/wind.html
Posted by:Mike | September 10, 2007 at 08:47 PM
I suspect the KW requires the 25mph wind. For a more prevalenvt 12.5 the V**3 rule would mean only 125watts. I would also presume that wind customers would like the product to have a lifetime similar to PV. I suspect there aren't all that many places with high enough average wind speed, which also has a low enough probability of >100mph to make it worthwhile.
The vertical axis should generate a considerable horizontal torque, which would be difficult to isolate from the vertical axis.
I've always assumed wind doesn't scale down very well. There is a reason that commercial windfarm turbines are now being built in the megawatt range.
Posted by:bigTom | September 10, 2007 at 10:01 PM
If you capture all available power produced, then payback is 21 years with grid power at $0.10/kWh using their 12mph numbers. With maintenance and other costs, payback could easily grow to 30 years. It will be totally worn out way before it pays for its own cost. And, this is the optimistic economics where all power from the unit is captured.
However, I doubt you can connect this as a utility-interactive distributed generator. Their UL 1741 approval is “pending” and it is not clear if they are seeking this specific utility rating covered in UL 1741. You would have to check with your power company but none I know of would allow it to be connected without the approved third party listing.
If you can’t connect it to the grid and “capture” all the power output into the system then it has very limited use. It could provide a small one-room cabin with lights if the wind is blowing. However, flash lights would be more dependable and cheaper. As far as putting them everywhere to add into the grid… forget it. The cost of this power is far too expensive compared to other sources of generation.
Posted by:JohnBo | September 10, 2007 at 11:18 PM
The average U.S. lifestyle consumes 1,550 watts. Assuming it meets the extremely optimistic performance specifications the average windmill output is 215 watts. We need 7.22 windmills per person, 29 windmills for a family of four.
We will need to install 6,290,000 units to match the output of one 1,500 MW nuclear plant with a 90% capacity factor.
Assuming a $400 cost for land, foundation, wiring, labor etc. the cost to replace one nuclear plant is $25.1 billion. If you want a modest level of reliability add about $10 billion for batteries, chargers and inverters.
But I doubt a plastic windmill is going to last 60 years, maybe 10 -20, so multiply accordingly.
Posted by:BILL HANNAHAN | September 11, 2007 at 12:30 AM
Based on these comments, where would they have obtained the money to even develop a prototype? Investors don't just pour money into a VAWT without some verification of the claims. Makes one wonder if this company is actually real.
Posted by:Angus | September 11, 2007 at 07:25 PM
Maybe they have a nitch market somewhere and decided to see if anyone else will buy one. Maybe they don't have an engineer. Who knows? Haha.
Posted by:JohnBo | September 11, 2007 at 10:36 PM
Isolated farms and communities can pay about $1.60 a kilowatt-hour using diesel generators, so there is a market for these small wind generators.
Posted by:Ronald Brak | September 12, 2007 at 01:30 AM
The depth and breadth of the ignorance in some of these comments is breathtaking. I guess it's easier to invent a reason why something won't work rather than look into how it can work.
Posted by:disgusted | September 12, 2007 at 09:08 AM
I agree with "disgusted", at least there are people out there doing their best to make our world a better place. The easiest is to just wait for big business to feed us the energy we need. Im all for being inovative and persistent if you think you have a good idea.
Posted by:greg | September 12, 2007 at 02:17 PM
The small wind turbine industry needs some serious competition. Four thousand dollars for a little 1kw wind generator? My God! Unfortunately, this sort of pricing is the norm. The U.S. government needs to greatly increase R&D spending and, ideally, to license the manufacture of good designs to low-income Americans. Otherwise, the only people who can save the world from global warming and high energy prices are the Chinese - with their willingness to make things for commodity prices, branding and intellectual property be damned.
Posted by:Tony | September 16, 2007 at 10:42 PM
There are several misleading comments above. Here are just some rebuttals.
First, these windmills compete with retail electricity, not wholesale as coal and nuclear do. My peak rate is about 28 cents/kWh. And as Ronald Brak mentioned, this system will quickly pay itself for many who are off the grid, which is a decent enough market for this technology to commercialise.
Second, plant cost may or may not be correct however it is misleading as the market for wind is not baseload, thus such plants will not get built (at least not anytime soon). Wind has plenty of room to grow (and dropping in price) before intermittency becomes a serious problem; these hypothetical plants are not yet relevant, and may very well never be as other technologies can cover for baseload. When the wind blows you get wind power. When it doesn't, so what? No one here said we should go 100% wind. If wind is economical, why not add it in the mix? It's an ultra low emissions power source. Worried about bird crunching? Horizon pollution? Lesser evils most would say, and anyway there are simple solutions to these simple issues.
Third, plant cost is also not relevant to the consumer. Real LEC is far more important. Utility scale wind is currently a complementary power source, which has a LEC of 3-7 cents/kWh. Curiously, this is about the same as nuclear fission.
Fourth, wind is not a "mature technology" in absolute terms. This term has been invented to compare technologies to each other. As in "technology X is more mature than technology Y". But literally there is no such thing as mature technology. The learing curve for wind is actually quite good, about 20 percent IIRC. Which is important as there is much more room for growth before problems arise.
You don't have to believe me. Just look at the worldwide private investments being made in wind power. With such simple empirical evidence, some of the above claims can be easily dismissed as irrelevant and/or false. No need to be disgusted.
Posted by:Calamity | September 19, 2007 at 11:43 AM
Calamity wrote: plant cost is also not relevant to the consumer. Real LEC is far more important. Utility scale wind [...] has a LEC of 3-7 cents/kWh.
Dong Energy says that 15-year levelized windpower currently costs 19 cents/kWh wholesale.
X-rates' currency conversion calculator says that DKK 1 = USD 0.187227.
Calamity wrote: Curiously, this is about the same as nuclear fission.
Assuming 60-year plant-lives, total levelized nuclear-energy costs are close to 2 cents/kWh.
world-nuclear.org/info/inf02.html
Posted by:Nucbuddy | September 20, 2007 at 12:40 AM
I see you're quoting that "independent" site again. Well at least they inventarised several studies which were more or less independent. The conclusion of which is 3.7 cents/kWh to 7.4 cents/kWh for nuclear.
Go with at least 10% discount rates as nuclear projects are proven historically to be financially risky.
For both wind and nuclear, it highly depends on what source you "shop for", as they all use different figures.
This one for the US:
http://www.awea.org/faq/cost.html
In the early 1980's, when the first utility-scale wind turbines were installed, wind-generated electricity cost as much as 30 cents per kilowatt-hour. Now, state-of-the-art wind power plants at excellent sites are generating electricity at less than 5 cents/kWh. Costs are continuing to decline as more and larger plants are built and advanced technology is introduced.
And also:
http://www.awea.org/windletter/wl_03may.html
In order to determine how much electricity a wind farm could produce, the first place to start is to get a good idea of the wind resource available. Since the energy in the wind is related to the cube of the wind speed [Power in the Wind (W/m2)= (wind speed)3 x ½(air density) x swept rotor area], small variations in the wind speed can lead to large changes in power output. For example, according to industry estimates from a couple of years ago, a wind farm at a site with wind speeds of 7.15 m/s (16 mph) would cost 4.8 cents per kWh, where one at a site with wind at 8.08 m/s (18.07) would cost 3.6 cents per kWh, a 25% reduction in cost.
Personally I think this one has good 2003 figures (which are better now in 2007, and they weren't even using the more economical larger turbines):
http://www.ewea.org/fileadmin/ewea_documents/documents/publications/factsheets/factsheet_economy2.pdf
The cost of electricity generated by wind power (2003 calculations) ranges from
approximately 4 - 5 €cents/kWh at sites with very good wind speeds to 6 - 8 €cents/kWh at sites with low wind speeds.
Power production costs of wind-generated electricity have fallen steadily as the technology has developed. The average cost for a coastal turbine has decreased from approximately 8.8 €cents/kWh (for a 95 kW turbine installed in the mid-1980s) to 4.1 €cents/kWh for a recent 1,000 kW machine A cost reduction of over 50% in the last 15 years has occurred for electricity from wind power. As a rule of thumb, manufacturers expect the production cost of wind power to decline 3-5% for each new generation of wind turbines they add to their product portfolio. Future cost reductions are a function of how the market grows. Looking forward, using analysis based on the “experience curve” method, it is anticipated that power production costs will continue to decrease. With a doubling of total installed capacity, the cost of production per kWh from new wind turbines will fall by between 9% and 17%.
Presently, the European market has doubled every three years. If, as Fig. 2 shows, the market takes 5, not 10 years to double, the cost would be 3.9-5.2 €cents/kWh instead of 4.4-5.6 €cents/ kWh. The EWEA target of 75GW installed in the EU by 2010 requires an annual growth rate of 16%, a doubling over 4.8 years.
The learning rate is less than I though but more than nuclear power. Independency is questionable as is the World Nuclear Site naturally. If you shuffle the figures around in a most optimistic (that is, unrealistic) way you'll get 3 cents LEC for present wind. (I've seen one with 2 cents LEC but I'm not even going to quote that one, that's how unrealistic it is). You also have to do that for present nuclear fission though, and ignore future value altogether.
Posted by:Calamity | September 20, 2007 at 06:54 AM
Calamity,
Are you assuming 60-year operating lives for those windpower plants? If not, why not?
Calamity,wrote: You also have to [...] for present nuclear fission [...] ignore future value altogether.
Are you considering that, for most of its 60-year operating life, a nuclear powerplant would be generating power with zero capital-cost?
Posted by:Nucbuddy | September 20, 2007 at 07:18 AM
Nucbuddy said: Are you assuming 60-year operating lives for those windpower plants? If not, why not?
No, because no windpower plant in existence has lasted 60 years. This is also true for the nuclear power plants you are promoting. Even if they would last 60 years technically, then consider that major refurbishment of some sort might be needed - which we don't know about - which would make the plant a "total loss" i.e. financially it may not last 60 years. Especially when you consider that a few decades from now, brand new nuclear fission plants will likely be cheaper, better, safer, more efficient etc, arguments that hold true for wind even more most likely.
The World Nuclear Association uses 40 years for nuclear power plants in some cases, seems more realistic to work with.
When no plant has lasted 60 years, can you really assume that it will? Only for well designed hydroelectric can such assumptions be used fairly accurately.
See this reference for an elaborate analysis of future wind power economics, including dealing with intermittency which they have concluded may be the one of the largest costs of wind power in the future. It uses 20 year windpower plant lifetime but rather optimistic cost targets:
http://www.ucalgary.ca/~keith/papers/65.Decarolis.2006.EconomicsOfWind.e.pdf
Nucbuddy said: Are you considering that, for most of its 60-year operating life, a nuclear powerplant would be generating power with zero capital-cost?
As mentioned above the 60 year operating life is speculative, and so is your statement as we do not yet know the required capital over the speculative 60 year operating life.
But that's not even my point. First, there's overnight capital cost, which discounting assumptions affect heavily. You are not seriously using 5% discounting figures for nukes are you now? Maybe in a state run socialist nuclear programme, such interest rates would be allowed. Are you assuming socialist power for the USA? 10% discounting would be reasonable, I seem to recall the nuclear industry standard 12% rate but I'm not sure. The overnight capital costs need to fall drastically for nuclear power.
And then, on the other hand, there's waste storage, which has future value implications. This is, of course, also speculative as the future development of waste disposal is not known.
Posted by:Calamity | September 20, 2007 at 07:54 AM
Calamity wrote: The World Nuclear Association uses 40 years for nuclear power plants in some cases
Could you please show me where the World Nuclear Association says it assumes a 40-year nuclear plant life?
Calamity wrote: the nuclear power plants you are promoting.
Please stop raping me.
Nuclear energy is neither any specific nuclear industry nor nuclear regulatory environment.
Posted by:Nucbuddy | September 20, 2007 at 10:40 AM
Nucbuddy refers to
http://www.world-nuclear.org/info/inf02.html
It does say that fuel and operation and maintenance costs are about 2 cents/KWH for nuclear. However, a chart further down, that includes capital costs shows for the EU at 10% discount rate:
Nuclear: EUR 4.0 - 5.5 c/kWh = US 5.4 - 7.4 c/kWh
Wind onshore: EUR 3.5-11.0 c/kWh = US 4.7-14.8 c/kWh
So while on average wind is more expensive than nuclear, in individual cases wind could be a little cheaper or twice as expensive.
For me, this Windspire turbine is useless, since we get very little wind at our residence. But let's see, at Calamity's peak rate of 28 cents/kWh, and assuming a production of 1900 kWh/year at 12mph average wind speed, it would take 7.5 years to pay for itself, or 1.5x the warranty period. Can't say I find that appealing. I suppose there's a niche market (probably off-grid) that it would appeal to.
Posted by:Clee | September 20, 2007 at 08:06 PM
In 1979 the government of Denmark initiated a 30% subsidy for the cost of building windmills. In 1999 they guaranteed wind power producers 85% of retail, 9 cents per kWh, for all the power they could make. They imposed a tax on fossil fuel to provide an additional 3.8 cents per kWh to wind producers.
Compare that with the cost to make electricity in the U.S. in 2005; hydroelectric 0.9 cents per kWh, coal 2.8 cents per kWh, natural gas turbine 5.9 cents per kWh, nuclear 1.8 cents per kWh.
http://www.eia.doe.gov/cneaf/electricity/epa/epat8p2.html
Denmark has the, ideal combination of optimum factors for wind.
• A population committed to wind power
• A government committed to wind power
• High energy prices
• Low energy consumption
• Large price guarantees
• Large government subsidies
• A small country with short transmission distances, each person lives within 50 miles of a shoreline
• Surrounding water creates mild winters and summers
• Excellent wind conditions for land and sea based wind farms year-round
• Mature in country wind turbine industry
In 2005 wind accounted for 18.5 % of the 751 watts per person Denmark used, only 139 watts of wind power per person.
Denmark’s huge wind subsidies have resulted in the highest electricity prices in the world, 29.5 cents per kWh, vs. 9.5 cents per kWh in the U.S.
http://www.eia.doe.gov/emeu/international/elecprih.html
Denmark also imports substantial amounts of nuclear power.
http://www.world-nuclear.org/info/inf99.html
The US completed about 5 reactors per year from 1970 to 1990 and they have been producing about 300 watts per person since then.
The primitive first generation nuclear power plants ramped up to 300 watts per person in 20 years, vs. Denmark’s 140 watts per person of wind in 30 years while the nuclear plants were charging less than one fourth the rate per kWh that the windmills received, and the nuclear plants were not given price and purchase guarantees.
The nuclear plants do not need backup energy storage service or voltage and frequency conditioning provided to the windmills free of charge by conventional power plants resulting in the emission of CO2 not attributed to the windmills, as it should be.
Windmill technology is highly advanced and they already operate near theoretical maximum efficiency. There is not a lot of room for improvement.
Many promising approaches to fission have yet to be explored.
http://thoriumenergy.blogspot.com/2006/04/welcome-and-introduction.html
If we had tens of thousands of sites around the world where the wind blows at a steady 30 MPH, 24 hours per day, 365 days per year, wind would be our salvation. But those sites do not exist. Wind mills are like hula hoops, a fad we are going through. 100 years from now there will be a few windmills, but they will never be abundant or inexpensive. Nuclear power can be both.
Posted by:BILL HANNAHAN | September 21, 2007 at 01:04 AM
Clee,
Because of the NIBMY factor, there is no such thing as onshore wind. Even the residents of Denmark refuse to accept onshore wind.
cphpost.dk/get/102943.html
cphpost.dk/get/102200.html
cphpost.dk/get/101575.html
cphpost.dk/get/98582.html
The more-acceptable alternative is offshore wind. However, that is more expensive.
http://www.cphpost.dk/get/101573.html
A minority of Danes admit that windpower, relative to the nuclear power -- and the other alternatives -- that Denmark relies heavily upon, is absurd.
cphpost.dk/get/91348.html
Posted by:Nucbuddy | September 21, 2007 at 12:08 PM
Nucbuddy writes:
"A minority of Danes admit that windpower, relative to the nuclear power ... that Denmark relies heavily upon, is absurd."
The article you referenced doesn't mention nuclear power at all. I interpret the article as saying that because of overcapacity, they don't need any new power plants right now, wind, biomass, nuclear or other.
"The total wind energy produced nationwide was only 11 megawatts in 2006 compared with 600 megawatts in 2000."
I suppose they mean only 11 MW of new rated capacity was added nationwide in 2006 compared with 600 MW added in 2000. After all, they generated 6,108 GWh of wind power in 2006. At 11 MW, that would be an impossible capacity factor of 6638%
I have no problem with a technology expanding quickly into its niche and then slowing down. So it seems wind has hit that point in Denmark, but onshore wind is still growing in the US and other countries. Apparently wind energy generation grew 45% last year in the US and 25% the year before.
www.eia.doe.gov/cneaf/solar.renewables/page/prelim_trends/table1.pdf
"Clee, Because of the NIBMY factor, there is no such thing as onshore wind. "
There is, as yet, no offshore wind in the US, so that double digit growth in wind last year must have been onshore. Every type of power plant has NIMBYs against them.
Posted by:Clee | September 23, 2007 at 11:37 PM