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12 Small Windmills Put To the Test In Holland

timothy posted about 5 years ago | from the blow-ye-winds-in-the-morning dept.

Power 510

tuna writes "A real-world test by the Dutch province of Zeeland (a very windy place) demonstrates that small windmills are a fundamentally flawed technology (PDF of tests results in Dutch, English summary). Twelve much-hyped micro wind turbines were placed in a row on an open plain. Their energy yield was measured over a period of one year (April 1, 2008 — March 31, 2009), the average wind velocity during these 12 months was 3.8 meters per second, slightly higher than average. Three windmills broke. The others recorded ridiculously low yields, in spite of the optimal conditions. It would take up to 141 small windmills to power an average American household entirely using wind energy, for a total cost of 780,000 dollars. The test results show clearly that energy return is closely tied to rotor diameter, and that the design of the windmill hardly matters."

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510 comments

Obvious? (-1, Redundant)

Devout_IPUite (1284636) | about 5 years ago | (#27639143)

So big tall poles with tiny itsy bitsy blades isn't efficient?

Somehow, this seemed kinda obvious.

Re:Obvious? (5, Informative)

Devout_IPUite (1284636) | about 5 years ago | (#27639167)

Wow, reading more I see how blatantly WRONG this summary is. There was one windmill that two of them would power a whole house. The "Energy Ball" one is the POS that takes 47 windmills, the rest are a lot better.

Re:Obvious? (3, Informative)

jonbryce (703250) | about 5 years ago | (#27639289)

And it had 5 meter blades, which are way to big for the average rooftop.

Re:Obvious? (2, Informative)

NewbieProgrammerMan (558327) | about 5 years ago | (#27639413)

It's best to put these on a tower anyway, so that they're up above all the turbulence created by stuff on the ground. So the blades are going to be a long way from your roof whether they're 2m or 5m long (as long as you care about the machine actually generating some power, that is).

Re:Obvious? (1)

stfvon007 (632997) | about 5 years ago | (#27639861)

The one that did the best was only 330cm in diameter the blades are half as long. diameter does not equal radius, even in german. Also the test results, if true, the best windmill would power 75% of the electric needs of the building where im living (3 apartments)

Re:Obvious? (1)

meatmanek (1062562) | about 5 years ago | (#27639219)

I am not an aeronautical engineer, but I'd guess energy output is roughly proportional to either wind speed times radius, or wind speed times radius squared.

So yeah. Small windmills which can only use a small amount of the wind are not going to harvest as much energy as a bigger windmill.

Re:Obvious? (5, Informative)

Anonymous Coward | about 5 years ago | (#27639403)

windspeed cubed and radius squared
not to mention the effect of turbulance on o/p

Re:Obvious? (3, Interesting)

rlk (1089) | about 5 years ago | (#27639837)

I plugged the numbers into a spreadsheet; it looks like power output is proportional to roughly D^2.5 (probably closer to 3 than to 2; I didn't do a best fit analysis). Cost is proportional to somewhere between D and D^1.5 (closer to D).

Note that the area is proportional to D^2, so bigger windmills actually extract more energy from the same amount of airflow.

Basically, the 1 meter windmill is a toy. It would be more practical to hook up a generator to a bike or rowing machine and use a battery or flywheel to store the energy -- that way you'd at least get some exercise out of it.

Actually, it would take 6 windmills (4, Informative)

zonky (1153039) | about 5 years ago | (#27639151)

rather than 141, if you used the Montana.

EPA would never let you build them (-1, Flamebait)

Anonymous Coward | about 5 years ago | (#27639237)

Doesn't matter, the EPA would never let you build private windmills.

Or this for that matter ...

OK, this is big news. A research team has worked out a way to nearly triple the efficiency of the Fischer-Tropsch process [sciencemag.org].

This means cheap synthetic hydrocarbons from coal are on the horizon. It probably sinks shale oil and biofuels for good - which is a good thing, as biofuel demand has been driving food prices higher. Potentially, it could make the U.S. - which has huge coal reserves - independent of foreign oil sources for the forseeable future.

Now watch for it: I [predict that the so-called "environmental movement" will scream in horror at this prospect, and we will learn yet again that they are mostly about enforcing eco-puritan poverty on us all rather than doing anything actually useful about actual ecological problems.

Re:EPA would never let you build them (4, Insightful)

Bucc5062 (856482) | about 5 years ago | (#27639345)

I was going to use my mod points to mod you informative, but when I got to the web site I got this little conundrum:
--------------
Subscribe/Join AAAS or Buy Access to This Article to View Full Text. The content you requested requires a AAAS member subscription to this site or Science Pay per Article purchase. If you already have a user name and password, please sign in below
--------------------
If you provide a link, please at least make it one where I don't have to pay, or provide the full text here.

As it is I can hardly determine if your thoughts about the EPA are a troll, or true. Try again.

Re:EPA would never let you build them (0)

Anonymous Coward | about 5 years ago | (#27639357)

So the environmental movement is worried about the environmental impact of burning all these fossil fuels. There may be a new way to switch from using oil to coal. This does nothing to help the environment, so no the environmental movement is not going to see it as a solution.

Re:EPA would never let you build them (3, Insightful)

NewbieProgrammerMan (558327) | about 5 years ago | (#27639383)

I don't think the EPA has any say in whether most people want to put a windmill on their property or not. I know people that have looked into putting one or more windmills on their farm (it turned out they don't have enough wind to make it worthwhile), and they didn't run into any EPA restrictions.

Neighborhood associations and local (city,county) regulations might be a different story, of course.

Re:EPA would never let you build them (1)

maxume (22995) | about 5 years ago | (#27639473)

There are investors working to put a couple of commercial wind towers up a couple miles from here. A woman with property in the area has been sending out monthly newsletters slamming wind power (infrasound, weird electrical effects, property values, etc.). Her agenda isn't going to stand up to the wind towers that just started operating 15 miles away that people can just go look at though.

Re:EPA would never let you build them (0)

Anonymous Coward | about 5 years ago | (#27639633)

A way to burn more hydrocarbons?

I think the environmental movement would be right to scream in horror at this prospect.

Re:EPA would never let you build them (0)

Anonymous Coward | about 5 years ago | (#27639789)

Doesn't matter, the EPA would never let you build private windmills.

Windmills have been long present in the rural USA. The EPA has never been involved before.

Re:Actually, it would take 6 windmills (0)

Anonymous Coward | about 5 years ago | (#27639529)

Yeah, the write up seemed unusually snarky. Still, 6 Montana's isn't anywhere near cost-effective for most people.

Re:Actually, it would take 6 windmills (4, Informative)

Kjella (173770) | about 5 years ago | (#27639547)

Which is also the biggest by far, 5m in diameter. The trend was very clear, despite the obfuscation with efficiency, cost and integer number of windmills all rolled into one. The bigger they are, the better they work.

Commercial 18m: 190000 / 143000 = 1.3 Euro/kWh
Montana 5m: 18508 / 2691 = 7 Euro/kWh
Skystream 3.7m: 10742 / 2109 = 5 Euro/kWh
Passaat 3.12m: 9239 / 578 = 16 Euro/kWh

And the crappiest were even smaller, though I'm not going to bother to do the math for them. In other words, none of these are worthwhile unless you absolutely can not throw up one big windmill instead of five small.

Re:Actually, it would take 6 windmills (3, Interesting)

TinBromide (921574) | about 5 years ago | (#27639733)

*cough* Hmm, sounds interesting, but don't current US customers pay 5-20cents per kWh?

I'm just gonna set this [michaelbluejay.com] down and back away while people flame me for endorsing coal/oil/nuclear based electricity.

Re:Actually, it would take 6 windmills (1)

Kazymyr (190114) | about 5 years ago | (#27639879)

The numbers above assume of course that you only have the generators working for 1 year and trash them afterwards... which won't happen in real life. On the other hand it does not account for any maintenance costs, spare parts etc.

Re:Actually, it would take 6 windmills (1)

KDR_11k (778916) | about 5 years ago | (#27639895)

I think those kWh figures were for one year or the duration of the test or something, I don't think it's the cost the system will have for its entire lifespan.

Re:Actually, it would take 6 windmills (2, Insightful)

clarkkent09 (1104833) | about 5 years ago | (#27639811)

Hmm, maybe I'm missing something since I can't read Dutch but why is this not completely obvious even without this experiment? The bigger they are, the more wind they catch. Sure the small ones are going to be somewhat cheaper but it seems like it's only a matter of the scale of the parts (such as bigger blades or whatever) so the cost is not going to be all that different.

Re:Actually, it would take 6 windmills (2, Informative)

mystuff (1088543) | about 5 years ago | (#27639853)

I assume you are from the US, or Canada perhaps?

Note that: 6 * 2687kWh/year = 16122 kWh/year

The US average electricity consumption (2005) is 12796 kWh (source [wikipedia.org]) so you could do with about 5 Montana Wind Mills (assuming your place of residence is as windy as Zeeland).

An average Dutch resident (of let's say Zeeland) uses only 6638 kWh / year (source [wikipedia.org]) , which means that 3 Windmills should be enough.

While I agree... (4, Interesting)

Maxo-Texas (864189) | about 5 years ago | (#27639159)

and even argued that sea based windmills would be inefficient recently (I think they will be attacked for their parts and be big targets if there was a war and I think maintenance in a high saline environment will be higher than they think)...

I do have to point out that
* any supplemental power comes off of the most expensive part of your bill (I pay more over 250kwh, and a whole lot over 750kwh).
* the more windmills we build, the cheaper it will get to make them.

Still- I think nano-solar type approaches are the most likely to work out.

Re:While I agree... (1, Informative)

Anonymous Coward | about 5 years ago | (#27639393)

You know what's really funny? Sailors all over the world use small wind generators to charge their batteries while at anchor.

It sounds like sea-based micro-turbines have a proven track record.

The article is bunk.

Re:While I agree... (3, Insightful)

westlake (615356) | about 5 years ago | (#27639715)

Sailors all over the world use small wind generators to charge their batteries while at anchor.

That doesn't tell me anything if I don't know the size of the battery or the rate of charge.

Sunforce Air X Marine Wind Turbine [amazon.com] 12 Volts. 400 Watts at 28 mph. 46" Blades. $750.

It strikes me that anchoring in 28 mph winds would keep you usefully occupied managing other problems.

Re:While I agree... (3, Interesting)

Alain Williams (2972) | about 5 years ago | (#27639803)

You know what's really funny? Sailors all over the world use small wind generators to charge their batteries while at anchor.

Yacht marinas tend to be built in windy places, so there is plenty to keep the blades going round. Also the power requirements of a small boat are very modest, much less than that of a typical house - high energy things (like cooking) tend to use gas or something.

If you think about it, the energy that a windmill can extract is going to be proportional to the amount of air that it can interact with - this will be roughly proportional to the sweep area of the blades or proportional to the square of the blade length. You will find that the power generated is roughly length^2 - do the math on the numbers that they quote.

Re:While I agree... (1)

benjamindees (441808) | about 5 years ago | (#27639687)

You think people would sail out into the gulf and attack fiberglass windmills for their copper windings? Has this happened to any of the hundreds of offshore windmills already in existence?

And then what if the windings are made from aluminum?

And what power generation source would not be a target in the event of war? Do you really think putting solar panels on your roof would exempt it from bombing if some country attacks the US?

Re:While I agree... (0)

Anonymous Coward | about 5 years ago | (#27639827)

Yes, because offshore windmills are much more attractive targets then, say, a nuclear power plant. Even a coal power plant would give you more loss-of-power for your bombs.

I'd certainly agree that the distance from shore and saltwater would increase costs to maintain off-shore wind power, but "targets during war" isn't one of the problems - at least not compared to other types of power plants with higher power density. Or if they're in love with the sea, our undersea cables.

I tend to agree that distributed solar power is better, though. Distributed power has obvious benefits with regards to transportation efficiency and difficulty of targeting, and solar panels scale down fine, as far as I know.

Executive summery (1)

Spyder0101 (1485837) | about 5 years ago | (#27639173)

Bigger is better but still expensive in the short and mid term, and only windy areas will benefit from them.

Re:Executive summery (2, Insightful)

loshwomp (468955) | about 5 years ago | (#27639277)

[...]and only windy areas will benefit from them.

Well I'm glad we finally cleared that up.

Re:Executive summery (1)

OrangeTide (124937) | about 5 years ago | (#27639673)

"only windy areas will benefit from them."

Shit really? As a venture capitalist I wish someone would have mentioned this before I invested.

Design hardly matters...? (4, Interesting)

Roogna (9643) | about 5 years ago | (#27639175)

Apparently it does matter, and these were obviously very poorly designed if three of them straight up broke.

Re:Design hardly matters...? (2, Informative)

zonky (1153039) | about 5 years ago | (#27639217)

Look at the table: - Energy Ball v100 (4,304 euro) : 73 kWh per year, corresponding to a continuous output of 8.3 watts - Ampair 600 (8,925 euro) : 245 kWh per year or a continuous output of 28 watts - Turby (21,350 euro) : 247 kWh per year or a continuous output of 28.1 watts - Airdolphin (17,548 euro) : 393 kWh per year or a continuous output of 44.8 watts - WRE 030 (29,512 euro) : 404 kWh per year or a continuous output of 46 watts - WRE 060 (37,187 euro) : 485 kWh per year or a continuous output of 55.4 watts - Passaat (9,239 euro) : 578 kWh per year or a continuous output of 66 watts - Skystream (10,742 euro) : 2,109 kWh per year or a continuous power output of 240.7 watts - Montana (18,508 euro) : 2,691 kWh per year or a continuous power output of 307 watts. Clearly, designs made a huge difference in output. The summary is nonsense.

Re:Design hardly matters...? (1, Insightful)

Anonymous Coward | about 5 years ago | (#27639263)

Another problem with the "design hardly matters" - even if all six of these _had_ completely failed, how on earth would even that be a basis to say that "design hardly matters, you cannot produce viable small windmills"?

In the early days of the car, if you took six different prototypes and concluded that they were all horrendous crap, it would be somewhat premature to conclude that 'car design is meaningless because it always ends up as crap'. Or rather: I am sure someone did, and that those someone were horse carriage manufacturers.

Re:Design hardly matters...? (1)

eagl (86459) | about 5 years ago | (#27639591)

The horse carriage manufacturers did ok (or at least they had options). They just had to shift production around a bit to make farm wagons, add a motor and call it a truck, etc.

The folks that got screwed where the buggy whip makers. There just aren't many ways to modify a buggy whip into something that meets a need in another market.

Re:Design hardly matters...? (3, Funny)

vlm (69642) | about 5 years ago | (#27639781)

The folks that got screwed where the buggy whip makers. There just aren't many ways to modify a buggy whip into something that meets a need in another market.

Ummm, try the booming erotic services market.

Re:Design hardly matters...? (5, Informative)

Anonymous Coward | about 5 years ago | (#27639937)

Clearly, designs made a huge difference in output

How the hell did this bit of poor reading comprehension get a 5 informative ranking?

Look at the size of the blades and the power produced. They are VERY proportional. Design didn't make much difference at all. What counts is the total surface area of wind you are taking advantage of. i.e. blade size.

The smallest unit had about 1/25 of the blade area coverage as the largest one, and produced fairly close to 1/25 of it's power.

Take home messages:

1) Design doesn't matter.

2) You are going to get ballpark 10 watts/square meter of wind in a windy area (avg 3.8 meters/sec wind)

4) A smaller number of large windmills are more cost effective to buy then a bunch of tiny windmills with the same surface area.

Original research? (-1, Flamebait)

Baron Eekman (713784) | about 5 years ago | (#27639177)

What is this doing on the front page?

The summary links to a report on an experimental setup. The poster draws his unverifiable conclusions. On Wikipedia we would say "no original research, please".

The costs are obviously high, as these are still in developmental stage. Most of the turbines performed below the expected yield, but for example the "Skystream", which was one of the cheaper models, output 2109 kWh, where 1360 kWh were expected. The test can easily be claimed to show this was a success.

New here? (5, Insightful)

benjamindees (441808) | about 5 years ago | (#27639391)

There is original research posted to Slashdot all the time, mostly in the field of computer science.

If there is enough data in the article to draw your own conclusions, then there is enough to discuss. This is a discussion site. If Slashdot only posted agreed-upon facts, then we would all just sit here with our dicks in our hands.

What the fuck is wrong with you people lately? This isn't wikipedia. We don't need anything filtered for truthiness by the retards responsible for that site.

Re:New here? (0)

Anonymous Coward | about 5 years ago | (#27639643)

"then we would all just sit here with our dicks in our hands"

I always had the impression that that was what most (male) internet users did, anyway.

Re:Original research? (4, Insightful)

Alomex (148003) | about 5 years ago | (#27639533)

Repeat after me: slashdot is not wikipedia.

Original research must appear somewhere in journals and the like. When it appears it becomes news. Slashdot is, guess what? news for nerds.

Now someone please mod the parent down.

Re:Original research? (1)

Baron Eekman (713784) | about 5 years ago | (#27639669)

To parent and sibling above:
There's usually a link to a news or scientific article somewhere. Here's a poster personally drawing conclusions as "ridiculously low yields", what good does that do? So I disagree: this is not news.

Re:Original research? (1)

EveLibertine (847955) | about 5 years ago | (#27639965)

Agreed. Wildly inaccurate summaries from authors drawing their own conclusions that aren't based on anything resembling reality is nothing new, and certainly isn't news.

Slow (4, Informative)

Anonymous Coward | about 5 years ago | (#27639199)

3.8 meters/second average is not a windy area, infact it's a Class 1 [doe.gov] wind speed. There are many places in the U.S. that are Class 3 or better, and you'd get much different results from those areas.

Re:Slow (5, Funny)

YrWrstNtmr (564987) | about 5 years ago | (#27639245)

3.8 meters/second average is not a windy area, infact it's a Class 1 [doe.gov] wind speed. There are many places in the U.S. that are Class 3 or better, and you'd get much different results from those areas.

Yeah. You'd have ALL of them break.

Re:Slow (1)

KeithIrwin (243301) | about 5 years ago | (#27639535)

From the picture, it's not clear that they made the towers high enough to be clear of the tree-line. As a result, they're probably not even capturing the strongest wind available in that area.

Re:Slow (4, Interesting)

radtea (464814) | about 5 years ago | (#27639583)

3.8 meters/second average is not a windy area

No kidding! This is a "study of wind power in an area that anyone who knows anything about wind power knows is unsuitable for wind power." Duh.

The Government of Ontario has an excellent resource on available wind in the province:

http://www.lio.ontario.ca/imf-ows/imf.jsp?site=windpower_en [ontario.ca]

The legend doesn't even go down to 3.8 m/s!

On my block, which is downtown in a lake-shore city, at 100 magl (metres above ground level, an acronym that does not appear to be defined anywhere on this otherwise excellent site) the average wind speed is 6 m/s, which is in the acceptable range. Because available power goes as the cube of wind velocity 6 m/s is nearly a four times increase in power over 3.8 m/s!

Small windmills are not for everyone, but this study is simply bogus if they're reporting the wind velocity correctly.

Re:Slow (0)

Anonymous Coward | about 5 years ago | (#27639639)

I've lived in places where (in the wintertime), the average daily windspeed is 16 meters per second. 3.8 is barely a breeze. When they have a windstorm and its blowing at 22 meters per second, gusting to 29 meters per second that these units would have to worry (people too). On the other hand, if you have roommates cooking (peksy university students!), and they are filling the house with smoke, then a few open windows on one side of the house and an open door or two can air the whole place out in about 2 seconds during such a windstorm.

Why don't they install tidal turbines instead (5, Funny)

SupremoMan (912191) | about 5 years ago | (#27639235)

Why don't the Dutch install tidal turbines in their fields instead, and wait for their country to flood.

Oh I kid, I kid

A little sad. (4, Insightful)

haeger (85819) | about 5 years ago | (#27639241)

It would take up to 141 small windmills to power an average American household entirely using wind energy...

I think this sais more about American household power consumption than it does about small windmills. Doesn't it?

I think it's a little sad and I would love to see a power-meter that shows exactly how much power you use when you use it. I think that would make people think.
Also it's a little amusing to read this site on how "bloated" KDE and Gnome are, or how bloated the linux kernel is, but still people use their terrible inefficient cars and houses that are energy-hogs.
Why isn't everyone here trying to make their home and car as efficient as comfortably possible? It's the "techie" thing to do.
And the tech is already available.
Remember that the cheapest energy unit is the one that you don't use.

Cost (0)

Anonymous Coward | about 5 years ago | (#27639325)

Because it is cost prohibitive to do what you seem to be demanding.

Re:A little sad. (1)

Idiomatick (976696) | about 5 years ago | (#27639399)

People that complain about Gnome bloat.... are probably not the same people that drive SUVs an hour to work. I think techies do or are at least more likely to live a more efficient lifestyle.

Re:A little sad. (2, Informative)

timeOday (582209) | about 5 years ago | (#27639425)

I would love to see a power-meter that shows exactly how much power you use when you use it.

You mean this [newegg.com]?

What I would like is "smart electronics" so I can push a single button on my way out and be sure I am not wasting electricity, without shutting off my fridge, alarm clock, and PVR. Maybe somebody can point me to that?

Re:A little sad. (1)

strength_of_10_men (967050) | about 5 years ago | (#27639621)

the kill-a-watt only measures what's plugged into it. no, more like this [theenergydetective.com]

T.E.D will measure the whole-house usage at the mains.

Re:A little sad. (1)

strength_of_10_men (967050) | about 5 years ago | (#27639679)

forgive me for replying to myself but...

forgot to post this interesting tidbit as well- google [google.org] is getting into the energy monitoring game as well. they're trying to enlist utilities and "smart" meters to report household power usage.

there are also a slew of start-ups trying the same thing with households as well as larger institutions [oberlin.edu].

Re:A little sad. (1)

Xolotl (675282) | about 5 years ago | (#27639875)

What I would like is "smart electronics" so I can push a single button on my way out and be sure I am not wasting electricity, without shutting off my fridge, alarm clock, and PVR.

I'd like this as well.

In a new installation it would be easy enough to arrange the wiring such that the fridge, alarm, and PVR were on separate circuits from the rest. Then the ordinary circuit breakers could be used to shut everything else off. In an existing installation it would be harder.

Re:A little sad. (1)

rickkas7 (983760) | about 5 years ago | (#27639659)

A meter that shows somewhat instantaneous and cumulative power use for your whole house. And it's wireless. http://www.bluelineinnovations.com/ [bluelineinnovations.com] My electric company (Green Mountain Power, Vermont, US) even subsidizes the purchase of them. I think mine cost $ 40 vs. $ 110 retail.

HMmm. I am curious (3, Insightful)

WindBourne (631190) | about 5 years ago | (#27639691)

When I spent time in Germany, I noticed that their homes really are quite similar to ours. The real issue was that EU has MUCH nicer climate throughout. With that said, I would like to see a comparison of electrical/Gas usage of a HOME, as opposed to a region. The reason is that most places try to compare regional uses which adds in manufacturing as well as travel.

Re:A little sad. (4, Insightful)

rossdee (243626) | about 5 years ago | (#27639693)

If americans lived in Holland, rather than California, Texas, or Florida, then they wouldn't need A/C for 90% of the year.

Re:A little sad. (1)

Mr. Slippery (47854) | about 5 years ago | (#27639841)

If americans lived in Holland, rather than California, Texas, or Florida, then they wouldn't need A/C for 90% of the year.

Excepting the elderly and the inform, air conditioning is not a "need" for most people in the U.S, either. Humanity survived for millennia -- even in California, Texas, and Florida -- without it.

Wear shorts, get a window fan and a attic ventilator, plant some shade trees.

And of course, folks in Holland need more power for heat -- and, I'd expect, for lighting -- than those in Florida.

Some thoughts (3, Informative)

Eudial (590661) | about 5 years ago | (#27639261)

The windmills seems to have been erected very close together. This may cause them to interfere with each other through turbulence. Also, some of them did fairly good. The Skystream and the Montana doesn't seem to be a total waste of money.

Re:Some thoughts (1)

will_die (586523) | about 5 years ago | (#27639321)

Being close is the whole point.
These have been pushed by the eco crowd as the solution, give each house one or two and the energy problem is solved; so they would have to be close.
BTW the way under the US stimulus bill, purchase one of these and you get a nice chunk back as credit.

Re:Some thoughts (1)

timeOday (582209) | about 5 years ago | (#27639497)

If you read this article as some sort of verdict on all possible sources of wind energy, you are missing the point. It's just a "consumer's digest" type review of a few current products.

Personally, I can't see everybody in suburbia having their own windmill. Solar cells, yes (I live in NM by the way). Having big wind farms, on the other hand, is already happening and works well. To avoid using up lots of land they should be on food farms, or offshore wind farms. (Or places like the TX/NM border which has nothing going for it except lots of wind). I also like the idea of tax credits for them, but the money should come from a carbon tax, perhaps in the form of cap and trade. We won't achieve sustainability until people bear the cost of their own pollution instead of doing nothing, which effectively socializes the costs.

Re:Some thoughts (1)

peragrin (659227) | about 5 years ago | (#27639519)

well one or two of these on the rough of a house, combined with ~2 KW in solar cells, and while you will still have to draw from the grid, your air conditioner is powered all summer for free. That by itself is a huge savings. realistically the average house has room for 3kw in solar panels. Now they won't work with their best efficiency but they will work better when you need them, the summer sun has a way of doing that.

Now if they can just get the cost down to the consumer so it is worth it.

Re:Some thoughts -panel cooling (0)

Anonymous Coward | about 5 years ago | (#27639913)

many parts of the world (eg middle east) run water tubing though black panels on the roof for heating hot water. Should be a simple change to plumb water lines feeding your tank under the panels. Could even rig an auto valve for daytime flow only.

Re:Some thoughts (1)

maxume (22995) | about 5 years ago | (#27639411)

They are pretty bad for the wind level where the test was done. Expensive electricity in Europe costs about €0.25, so €10,000 goes an awful long way. Even at the €0.318 quoted for Denmark, the €10,000 goes pretty far.

I certainly am not going to run out and buy something that barely pays for itself in 15 years (and that is without accounting for interest and maintenance...).

(Price quotes from here: http://www.energy.eu/#domestic [energy.eu] )

Re:Some thoughts (1)

Idiomatick (976696) | about 5 years ago | (#27639577)

It doesn't matter. At this rate if you spread them out further you would have to cover more land than the country has. Wind power has always been a complete waste of time (even if these numbers are silly).

If we harvested ALL the wind of the entire planet at 100% efficiency. It would only produce 72TW. Unfortunately we can't come remotely close to 100% assuming we can get the energy of 5% of all the moving air... That is 3.5TW. (Global consumption NOW is 15TW). That power is also intermittent which means we need to store it meaning more loss. Not to mention if we covered the entire planet there would be problems involved. We'd probably kill all the birds on the planet and use all the easily mined metal on the planet. Plus it would cost countless trillions of dollars. All that for what? 25% of our current energy consumption.

For a comparison a nuclear plant makes 8GWh each. So we would need 500 nuclear power plants to have the equivalent power production of covering the entire planet with windmills. Giving a cost per MWh thousands of times less.

The idea that windmills even get mentioned is embarrassing. Put the biggest windmills we can make in the top 2~3% windiest places in the world and be done with it.

Re:Some thoughts (1)

KDR_11k (778916) | about 5 years ago | (#27639975)

I recall reading a decade ago or so that there's only enough nuclear fuel for maybe a hundred years, would it really be feasible to run the whole world on nuclear power for long?

Solved: +1, Innovative (-1, Flamebait)

Anonymous Coward | about 5 years ago | (#27639315)

" It would take up to 141 small windmills to power an average American household entirely using wind energy, "

Get rid of the 4 televisions, central air conditioning, 2 dishwashers, 2 refrigerators, and the taser.

Yours In Communism,
Kilgore Trout [youtube.com]

Re:Solved: +1, Innovative (1)

Wonko the Sane (25252) | about 5 years ago | (#27639605)

central air conditioning

I bet you don't live in a location that frequently experiences >90% humidity and >100F temperatures at the same time in the summer.

Re:Solved: +1, Innovative (0)

Anonymous Coward | about 5 years ago | (#27639655)

Haha, this should be modded funny if only for the taser comment.

Do the math (4, Informative)

Ancient_Hacker (751168) | about 5 years ago | (#27639331)

There are two very simple scaling laws at play here.

First off the wind power intercepted goes up as the square of the rotor length. So larger is better, a lot larger is a whole lot better. You also get the free benefit of stronger winds as you have to raise the center point as to not hit the ground.

Next the power goes up as the CUBE of the wind speed. So it really pays big to find a real windy spot.

So your basic $30,000 small, low windmill placed on your typical house are real big losers.

And they needed a study for that? (5, Informative)

lnxpilot (453564) | about 5 years ago | (#27639379)

It's physics 101.
Capturing a larger cross-section of moving air is more efficient.

The reverse is also true (generating thrust):
Turbofan engines are more efficient at lower air-speeds than straight turbojets.
Moving a small amount of air at a higher velocity will create more wasteful eddies than moving a larger cross-section of air at a lower speeds.

Helicopters are the extreme case WRT aircraft.
You need a lot less power to make a helicopter hover than a ducted-fan or jet VTOL aircraft (like the Harrier or the JSF).

It reminds me of people who are surprised that electric cars / hybrids take up the most energy when they accelerate.
Duh, that's when you're actually gaining kinetic energy.
In cruise, you're just fighting drag (air) and friction (road).

nitpick (0)

Anonymous Coward | about 5 years ago | (#27639927)

Moving a small amount of air at a higher velocity will create more wasteful eddies than moving a larger cross-section of air at a lower speeds.

Although true, that's not the reason turbofans are more efficient.

The reason has two parts.

  1. Thrust (dp/dt) / power (dE/dt) goes like 1/v
  2. Aircraft only require a relatively constant thrust (while cruising) to overcome drag.

Since aircraft have an unlimited supply of fuel mass, they can go quite far in terms of optimizing for energy efficiency. Within practical limits, of course. The exhaust has to be faster than the intake, for instance.

Re:And they needed a study for that? (1)

cherokee158 (701472) | about 5 years ago | (#27639989)

Comparing helicopters with jet-powered VTOL aircraft is an apples and oranges comparison. The helicopter is utilizing lift to stay aloft...the Harrier/JSF use only thrust to hover. They are both moving air downward, but they are using very different methods, and I don't think you could easily compare their efficiency based on a narrow portion of their performance envelope. At 40000 feet, a Harrier has far better efficiency than a helicopter, which would be plummeting like a rock with its rotor spinning uselessly in the thin air.

Skystream returns 4% (0)

Pascal Sartoretti (454385) | about 5 years ago | (#27639471)

The Skystream produced 2'109 kWh per year, which makes around 422 Euros at the current price of 0.2 Euros per KWh (do some googling...). For an investment of 10'742 Euros, this makes a return of 4% per year.

With the current economy, this seems like a good investment...

Re:Skystream returns 4% (1)

maxume (22995) | about 5 years ago | (#27639623)

You need to account for the depreciation of windmill. It won't be worth €10,742 after 1 year of use. It certainly won't be worth €10,742 after 10 years of use.

Re:Skystream returns 4% (1)

Idiomatick (976696) | about 5 years ago | (#27639729)

4% a year return rate on a machine that must function and is costly to repair. And that is WITH government funding your project. That means it will probably result in a return of -4% a year. That doesn't invalidate your point about the investment vs the economy... but still.

Re:Skystream returns 4% (2, Informative)

plague911 (1292006) | about 5 years ago | (#27639905)

Except for the large sunk costs of 10742 euros. By that math it would take around 25 years to break even, assuming no maintenance and no interest or discount rate. So in other words that's garbage.

For a change could everyone read the article (3, Informative)

iamflimflam1 (1369141) | about 5 years ago | (#27639493)

This has to be the worst summary ever. Please take the time to look at the article and do the maths yourself.

Re: Free Energy (-1, Troll)

Anonymous Coward | about 5 years ago | (#27639505)

Free energy devices are out there (such as the "Joe Cell") but are being ruthlessly suppressed by the corporate elite because they would lose control of the populace. see: George Green's magnetic motor [youtube.com] as one of many examples out there. Take the Red Pill.

Re: Free Energy (2, Insightful)

couchslug (175151) | about 5 years ago | (#27639717)

"Free energy devices are out there (such as the "Joe Cell") but are being ruthlessly suppressed by the corporate elite because they would lose control of the populace"

They cannot be suppressed if the inventor makes them instantly available under appropriate Free and Open licenses via the internet.

Youtube videos prove nothing Inventors should actually build a working model and offer it for testing by neutral third parties, and should furnish specific plans so anyone wishing to build their own example and test it in public can do so.

Re: Free Energy (1)

Alain Williams (2972) | about 5 years ago | (#27639961)

So, did you work out where the energy was coming from ?

I reckon that it was the guy's hand that was moving.

If this was really capable of generating energy you would have seen a video of a static setup driving a small dynamo - or something similar.

PV is more cost effective than small wind turbines (3, Informative)

jeroen8 (1463273) | about 5 years ago | (#27639737)

On the Renewable Energy website OliNo there is an article Test results small wind turbines [olino.org] website with some more background on this test. The first test results show that a PV system (Solar Energy) is more cost effective than these small windturbines. The Dutch article [olino.org], which is more up-to-date, show also the last measurement results of the windturbines (11 months of data). The conclusion is the same. However, it was found out, that an official wind measurement station of the KNMI only 14 kilometers (8.8 miles) away form the test site has an average windspeed which is twice of of the test field. This could explain the low yield of the windturbines.

Obligatory futrama (0)

Anonymous Coward | about 5 years ago | (#27639783)

Morbo: Direct your attention now to the African turtles seen here migrating to cooler homes in Holland. Morbo wishes these stalwart nomads peace among the Dutch tulips.

Linda: I'm sure those windmills will keep them cool.

Morbo: Windmills do not work that way!

It's in the Netherlands (4, Informative)

Daimanta (1140543) | about 5 years ago | (#27639815)

not in Holland. Holland is the combination of North-Holland and South-Holland, both provincies of the Netherlands. The Netherlands is the country as a whole. The Kingdom of the Netherland is the Netherlands plus the Netherland Antilles and Aruba. Zeeland(Sealand) is a provincy seperate from Holland.

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