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Vertical-axis wind turbine spins into business

Posted June 02, 2008 11:05 AM

From Crave: The gadget blog:

Mariah Power says its Windspire vertical-axis wind turbine is now commercially available, after having passed performance tests. The Windspire costs $4,995, which includes the inverter, pole, and other equipment. Typically, small-wind turbines such as Southwest Windpower's 1.9-kilowatt Skystream, are best suited for homes with a substantial amount of land. Mariah Power said the Windspire is aimed at residential customers in urban, suburban, and rural areas. It has already been installed in a handful of U.S. locations. "(Its) efficiency is on par with most propeller-based wind turbines, but it is priced much lower. It is also much quieter because the rotor glides through the air at only a third the speed of propeller blades, and it can capture wind instantly from any direction," Mariah Power CEO Mike Hess said in a statement.

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#1

Re: Vertical-axis wind turbine spins into business

06/02/2008 9:41 PM

Wasn't there a simuliar drive system a ship that Jacques Cousteau develop and built, I don't beleive it was the Calypso?

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#8
In reply to #1

Re: Vertical-axis wind turbine spins into business

06/03/2008 5:28 AM

Hi phoenix911.

Yes you are right! It was going to replace large engines in ships, or so they said at the time?

Spencer.

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#13
In reply to #1

Re: Vertical-axis wind turbine spins into business

06/03/2008 4:28 PM

Hi phoenix911

You wrote: Wasn't there a simuliar drive system a ship that Jacques Cousteau develop and built, I don't beleive it was the Calypso?

It was not the "Calypso" but the "Alcyone" It did not have a VAWT but a turbosail. The closest thing to this is most probably Shadotec's Wingsails. According to a recent press release, when fitted to a cargo vessel as well as to a seismic exploration vessel, some fuel savings were achieved.

Brgds

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#15
In reply to #13

Re: Vertical-axis wind turbine spins into business

06/03/2008 6:57 PM

Recently, a cargo ship used a giant kite and lopped 20% off its normal fuel bill.

If anyone needs more details, I will chase it up on the web.....or try yourself!!

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#16
In reply to #15

Re: Vertical-axis wind turbine spins into business

06/04/2008 7:26 AM

Hello Andy Germany

that kite-assisted ship: http://www.seacoastnrg.org/2008/02/06/kite-ship-to-demonstrate-fuel-savings-with-wind-power/

Such an obvious fuel savings device should be used.

Bring back the sailing ships, that's what I say.

Kind Regards....

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#17
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Re: Vertical-axis wind turbine spins into business

06/04/2008 8:52 AM

There are even videos on their website showing the unfolding and operation of the kite. Bigger versions are comming up. But this is off-topic.

http://www.skysails.info/

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#18
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Re: Vertical-axis wind turbine spins into business

06/04/2008 9:44 AM

Me too!!

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#2

Re: Vertical-axis wind turbine spins into business

06/02/2008 10:50 PM

In the 1970's I bought a wall poster that had the different windmill designs and the efficiency of each type of windmill. I know where I have the poster in storage but can't get to it right now.

I have seen over the internet windmills sized for charging the batteries on a sailboat.

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#3

Re: Vertical-axis wind turbine spins into business

06/02/2008 10:59 PM

Why does this sound like someone reinvented the Savonius turbines?

I've seen more than a few of these made from 55-gallon drums over the years.

Allen

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#5
In reply to #3

Re: Vertical-axis wind turbine spins into business

06/03/2008 3:39 AM

What you see is not at all a Savonius turbine.

Check out VAWT on google and learn a bit before you judge.

VAWT's have significant advantages over HAWT, one of the most important is the unidirectional wind acceptance and low noise generation.

In fact these types of turbines can perfectly be used on private buildings and on every lighting pole along the highways.

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#6
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Re: Vertical-axis wind turbine spins into business

06/03/2008 4:43 AM

At 5 cents per kWh the annual production is 2000*0,05 = 100 Dollar

At 5 percent interest rate the annual interest is 5000*0,05 = 250 Dollar

How does this stick together financially?

It sure looks like an interesting way of impressing your neighbours while loosing money...

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#9
In reply to #6

Re: Vertical-axis wind turbine spins into business

06/03/2008 6:50 AM

Nice way of thinking but after all it brought us in the actual situation of 135 $/barrel: short sighted management.

You live in Paris, capital of France. We are really impressed by the way they produce their electricity: nuclear power stations on the border.

France produces more than 80% of its power through nuclear fission. We only 60%.

We also have to pay Suez as they are so kind of owning our production capacity.

The picture is getting quite different as I have to pay more than 0.05 €/KWh

For each MWh produces I get € 85,- when done through wind, € 450 if it comes from PV systems.

The investment can be deducted from the annual income tax. (40% of my investment comes back through it)

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#10
In reply to #9

Re: Vertical-axis wind turbine spins into business

06/03/2008 7:10 AM

Hallo Gwen,

Wat is de prijs van energie?

It all depends how much you are willing to pay for energy. Today we see truckers and fishermen protesting in Europe for high gasoline and diesel prices. Some filling stations in the area here are at more that 1,50 Euro per liter. But if you manage to save a lot of fuel for your everyday trip by getting an economical car it is not a problem. If we allow trucks of more than 60 tonnes , the cost per tonne-km will be low enough again.

Same with electricity. Where do you use it for? Air-conditionning, interior heating, heating of your tub water? If you are a smart engineer you can save huge amounts of energy cost by better use of the sun for your heating requirements at relatively low cost. Then your budget for electricity can be fine even if it goes very high compared to todays standards.

Nuclear in France is cheap. I agree. Not all powerstations are close to the border. They are all over the country.

For countries running of fossil fuel and gas powerstations, huge savings can be made by distributed combined heat -power generation. Let us all change habits. Lets work on savings, they are the cheapest way to get to affordable energy requirement. Far cheaper than putting additional solar and wind power. (I do not count for subventions on these items because in the end it is government money that originated from my taxes, taxes is just money going around to change habits of individuals, i hope for the better of the community)

The cost calculation of the windmill mentionned above really amazed me. How can a company put information on a website that should logically refrain potential customers from purchasing? Is that company counting on the stupidity of the population or does it really believe that the image you get when having such a device is so much more valuable than the extra money spent on energy?

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#12
In reply to #10

Re: Vertical-axis wind turbine spins into business

06/03/2008 10:58 AM

Beste Randolp,

Niet genoeg.

What I don't get is the logic that the community has to pay for the expensive fuel for trucks, farmers and fishing boats.

There are already to much trucks on the roads, a bit less and more intelligent grouping and alternative transport methods could solve a lot of the actual problems.

After all it are the multinationals who decided to close local production and move to the east with everything who are to be blamed. For a littlebit of extra gain at the end they consume way more fuel in driving the empty cans from Spain to Italy, where they can be filled with tomatos which go back to Spain. Only because the EU gave money to build the cannery in Spain and to grow tomatos in Italy. So farmers in Spain are forced to stop producing Tomatos and the cannery in Italy is closed. In between 100 trucks "filled" with empty cans.

Fish has never been so expensive, strange that the fishermen see nothing from this. This is something that the EU needs to solve.

The same is valid for a lot of agricultural stuff, somehow they jumped in a market where the importance of energy imput is high. They need to keep their plants warm.

Now that the energy cost is tripled in a few years time the whole business case crashes. But it is this business model which invoked the rise, so I feel no need to rais my tax level again and pay for it.

I know that the nuclear stations are all over the country and even you know that we also tend to shift the problems to the border. It was only literally speaking.

Personal wind power wil never gain influence when prices are at this level, the market is such that it is only sold to those who want to pay as they need to have it.

PV is in the same situation: cost is high but nevertheless you see it popping up everywhere.

With small scale wind it will go the same direction, as soon as decision makers see the value they will regulate the market so that it takes of.

Gwen

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#25
In reply to #12

Re: Vertical-axis wind turbine spins into business

06/05/2008 4:44 AM

Do you pretend that things go way better in the US? That no social disasters are possible? That you have such a fantastic social recovery and help system?

Please make us laugh a bit.

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#28
In reply to #25

Re: Vertical-axis wind turbine spins into business

06/05/2008 6:48 AM

Hi Gwen, awful and incorrect sentence you wrote:-

Please make us laugh a bit.

You should have written:-

Please carry on writing such comments and make us laugh as much again and again and again......

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#29
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Re: Vertical-axis wind turbine spins into business

06/05/2008 6:52 AM

Andy, I tried to stay polite.

But as usual you are correct.

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#30
In reply to #29

Re: Vertical-axis wind turbine spins into business

06/05/2008 9:34 AM

You stay exactly as you are, I can be nasty enough for the two of us!!!

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#11
In reply to #9

Re: Vertical-axis wind turbine spins into business

06/03/2008 10:34 AM

I like that "nuclear power stations on the border" idea. Since we're going to build a huge ineffective fence on our southern border, maybe we should build a line of wind turbines instead.

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#7
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Re: Vertical-axis wind turbine spins into business

06/03/2008 5:21 AM

Hi Gwen...you are right of course...

I think Savonius machines are characterise as 'drag' powered whereas the other sort are 'lift' operated...
I've always been confused by them, every time I see an explanation of how they work there is a dubious vector diagram which seems to show the force acting in toward the axis...

It would be nice to see a lucid explanation from someone (BTW I do realise that circular motion can be described as acceleration towards the centre..but I still a confused Cat)

Del

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#19
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Re: Vertical-axis wind turbine spins into business

06/04/2008 3:36 PM

Savonius turbines are horizontal axis.

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#20
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Re: Vertical-axis wind turbine spins into business

06/04/2008 5:36 PM

Its possible, but exceedingly seldom I feel. I have never seen one mounted horizontally personally, only vertically.....which is why they are called VAWTs.....

On the link at the bottom, you will note that the very first sentence says:-

Savonius wind turbines are a type of vertical-axis wind turbine (VAWT), used for converting the power of the wind into torque on a rotating shaft.

See this link to help you to better understand a Savonius Turbine.

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#21
In reply to #20

Re: Vertical-axis wind turbine spins into business

06/04/2008 9:20 PM

OK, Lets Concentrate...

If they are vertical axis, is there a thrust vector also ?

If so then why not make a horizontal axis, a double overhung generator, like they do with hydro waterwheels, the thrust from two ideal (right & left-hand) hydro runners (wind turbines) cancels out. They also normally have sleeve bearings on the end of the runner shafts for support and to minimize sag/bending of the shafts/time for the shafts to straighten/ to minimize vibration.

I also understand the wind velocity is higher the further above the ground.

While driving across the interstate in the Dakotas I saw a vertical axis turbine with multiple "sails" (maybe 6 foot tall), can't remember the name for that type of windmill or exactly where it was.

Also why don't they have some type of wind "concentrator" for those days when the wind speed is too low ? I have seen many of the canyons full of windmills and flat farm fields also.

The nukes suffer from NIMBY (Not In My Backyard) syndrome, just like refineries and many other things that are necessary and beneficial to our survival.

On the east coast off Massachusetts they wanted to put windmills, this was so they could also put oil wells and natural gas recovery, they should be required to do all 3 from each platform permitted (oil or natural gas, wind turbine, wave power) and then...use the platform weight like a anchored bobber to generate power.

Because it takes energy to make the materials and the enegy conversion machines, it must not become like ethanol, where it takes 10% more energy then you get from it.

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#22
In reply to #21

Re: Vertical-axis wind turbine spins into business

06/04/2008 9:53 PM

GA - My feelings exactly

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#26
In reply to #21

Re: Vertical-axis wind turbine spins into business

06/05/2008 6:44 AM

The biggest drawback of horizontal windmills is that they are directional, you have to turn them to face the wind. Most vertical axis windmills work (without any other changes to the unit) with wind from any direction.

A further plus is that there are VAWTs that are made up to look like a small outbuilding and therefore are not such a "blot" on the landscape, they look so good that nobody would ever guess that a windmill is in there running!!!

Most of the rest of your post I could not see what point you were trying to make, you appeared to just be "rambling", perhaps you would be so kind as to bring in some more coherent points that we can fully appreciate.

Thanks in advance.

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#4

Re: Vertical-axis wind turbine spins into business

06/03/2008 2:48 AM

Hi,

this is really Savonius having shown a bad efficiency.

There is existing a modification which is claimed to be much better that is using blades that are spiraling half(?) way around the circumference.

If enough wind is existing and low power is sufficient, why not if competitive.

Should be simpler than the ordinary types.

RHABE

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#14

Re: Vertical-axis wind turbine spins into business

06/03/2008 4:37 PM

Hi,

Gwen, you are right this is Darrieu.

But nevertheless it has a bad energy recovery.

This can be explained by two factors:

a. : the blades have (on their way around) two times best efficiency and two times no efficiency but drag.

b.: the blades are subject to bending thus limiting maximum speed.

This bending has two components: one from centrifugal forces the other from lift.

In a horizontal axis wind turbine (HAWT) there is only the lift component.

This allows for considerably higher velocity.

So better efficiency on the way round and an allowable higher velocity clearly gives priority to the horizontal turbine if energy harvesting in relation to investment is calculated.

The reorientation to changing wind directions is no longer a problem.

I agree that the vertical rotor is easier to do at home.

What I want to see (may be I missed it) is a vertical axis machine with horizontal spikes or discs that support (vertically elongated) sails. This would overcome the speed limit but still have higher drag than the horizontal axis machine. But as the sails are much less expensive than profiled blades this would lower cost and thus influence the calculation.

Has anybody tried this?

RHABE

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#23
In reply to #14

Re: Vertical-axis wind turbine spins into business

06/04/2008 10:12 PM

"What I want to see (may be I missed it) is a vertical axis machine with horizontal spikes or discs that support (vertically elongated) sails. This would overcome the speed limit but still have higher drag than the horizontal axis machine. But as the sails are much less expensive than profiled blades this would lower cost and thus influence the calculation."

Is this like a really large boat propellor on a vertical shaft ?

Why not a horizontal shaft with a concentrator ahead of it to shield the "returning blades" ?

This could have some thrust ?

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#24
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Re: Vertical-axis wind turbine spins into business

06/04/2008 11:35 PM

I'd be interested to see how well a concentrator would work (and I can only imagine how one would be constructed). Unless you're in an area that has a steady blow from a single direction I would think it might be a bit cumbersome and unwieldy.

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#27
In reply to #23

Re: Vertical-axis wind turbine spins into business

06/05/2008 6:46 AM

If you had used the link in one of my previous posts, you would have seen pictures and an explanation of exactly how it works.......if you cannot find that link, let me know and I will post it again for you.

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#31
In reply to #14

Re: Vertical-axis wind turbine spins into business

01/10/2009 1:13 AM

It is very important to recover turbulent wind when thinking of fully distributed power in urban or suburban areas. This is where savonius and darrius type turbines excel. If you go to http://www.aerotecture.com or http://www.tesnic.com, there are a couple of examples of sails in the aerotecture case or discs in the tesla-type turbine. The former seems to be working and I don't know about the latter.

Of course, the original post of this thread appears to show elongated blades supported by horizontal bars - is this what you meant? I was thinking the same thing about the sails potentially lowering the cost and thus being more universally acceptable. I would love to try it, but cannot afford the time, materials, or fabrication equipment. Right now I'm hot-gluing a large coffee cup to two old AOL cds to observe a savonius/darrius combination. All the best, NS

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#32

Re: Vertical-axis wind turbine spins into business

01/11/2009 10:15 AM

We should keep in mind the time to return on investment.

In one of my previous post I mentionned energy production with financial returns inferior to interest rates of the investment in the wind turbine. This is to be avoided of course. In the end it all comes down to cost and profitability.

I came across an interesting book this week that tells how to make wind turbines yourself with recuperated parts. It mentioned car alternator and 12V batteries and inverter. Though car alternators are not efficient at low speed they come for free in the scrapyard...

If you need better efficiency of alternator you should then opt for 2-blade turbine that runs faster, most probably equipped with a pulley drive to increase speed on alternator shaft.

Also you could opt for a home made permanent magnet motor. There are many links about this on the web. It seems like a rewarding exercise to make your own PM generator from recuperated Volvo brake disks (as I found on one of the sites).

I believe that if you heat your hot water with wind power you probably don't need battery pack and inverter, just a resistance and that is something you can find very cheap. Store the energy in low value energy that you need anyway and avoid the high cost items. Be smarter than the rest of the world.

Home made wind turbines are actually quite interesting as an engineering exercise. I think we should stop looking for highest efficiency of the installation for quality electricity production. Think how to amortize as soon as possible.

By the way : Has anyone got a link to cheap blades?

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