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Power Earth

12 Small Windmills Put To the Test In Holland 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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12 Small Windmills Put To the Test In Holland

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  • While I agree... (Score:5, Interesting)

    by Maxo-Texas ( 864189 ) on Sunday April 19, 2009 @04:42PM (#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.

  • by Roogna ( 9643 ) on Sunday April 19, 2009 @04:44PM (#27639175)

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

  • Re:Slow (Score:5, Interesting)

    by radtea ( 464814 ) on Sunday April 19, 2009 @05:35PM (#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: []

    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.

  • by TinBromide ( 921574 ) on Sunday April 19, 2009 @05:52PM (#27639733)
    *cough* Hmm, sounds interesting, but don't current US customers pay 5-20cents per kWh?

    I'm just gonna set this [] down and back away while people flame me for endorsing coal/oil/nuclear based electricity.
  • Re:While I agree... (Score:4, Interesting)

    by Alain Williams ( 2972 ) <> on Sunday April 19, 2009 @06:00PM (#27639803) Homepage

    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:Obvious? (Score:4, Interesting)

    by rlk ( 1089 ) on Sunday April 19, 2009 @06:03PM (#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.

  • by Anonymous Coward on Sunday April 19, 2009 @06:28PM (#27640035)

    Yep, and here is the pilot study on this idea:

  • by Idiomatick ( 976696 ) on Sunday April 19, 2009 @06:56PM (#27640189)
    Oh and the depressing statistic is cars.
    Dutch use 339L/person/year (2000)

    US use 1672L/person/year (2002) []

    Around 5x as much gas used yay.
  • by damn_registrars ( 1103043 ) <> on Sunday April 19, 2009 @07:55PM (#27640547) Homepage Journal
    For those who wondered where the country New Zealand got its name; or more so where the "old" Zealand is:

    Dutch province of Zeeland

    There is your answer.

  • by MightyYar ( 622222 ) on Sunday April 19, 2009 @09:48PM (#27641113)

    I never understood why we don't use rowhouses.

    Who is "we"? In the US, I'm having trouble thinking of cities without extensive use of row homes (or as they are now affectionately called - townhomes).

    Personally, I hated living in them. Loud neighbors and an inability to be loud yourself, usually no garage and general parking woes, skimpy yard space, darker since you can't have windows on the sides, and the fact that a single fire can wipe out multiple units quickly. As for the heating savings... my cheap, poor next door neighbors never turned on their heat, so we (along with our neighbor) ended up paying for their heat as well as our own. And none of the owners could agree on a roofing/siding/paint scheme, so the whole block looked like it was decorated by an insane person.

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

    by Acer500 ( 846698 ) on Sunday April 19, 2009 @09:55PM (#27641145) Journal

    Nuclear does make a big target - but any centralized power system will. Not sure what the effect of a 20k non-nuclear bunker buster would be.

    Wow, you Americans sure are paranoid... (if you are not American, I'll be surprised)

    The nuclear energy debate has come up on my country, and the #1 issues are the fear of an accident, and how to manage waste. No-one even THOUGHT about the possibility of a terrorist attack. Makes me glad to live in Uruguay.

  • by gstovall ( 22014 ) on Sunday April 19, 2009 @09:59PM (#27641169) Homepage

    I run about 30,000 KWH per year in my house. I was pretty distressed by this amount compared with both the Dutch and US averages, until I factored in:
    1) All electric -- no gas
    2) Climate where Heating Degree Days outnumber Cooling Degree Days 3 to 1
    3) This house, even though it's all electric, consumes only half the electricity of my PREVIOUS house, which was not all electric
    4) 6 people live here
    5) I work at home, so the house is always occupied
    6) I run a small datacenter at home, so not only does all the equipment have to be powered, it has a separate cooling unit.

    Given that, I don't feel AS bad. However, it's still a lot of electricity. Yes, I replaced all incandescents with fluorescent about 10 years ago, so that helps.

  • Re:While I agree... (Score:5, Interesting)

    by Rei ( 128717 ) on Sunday April 19, 2009 @10:05PM (#27641189) Homepage

    Yes- I believe in a world where people strip houses of wiring and pirates attack ships, that the large commercial windmills that contain very large copper cores

    Those would have to be some brave freaking looters [] who really know what the heck they're doing [] if they don't want to, you know, die.

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

    by Anonymous Coward on Sunday April 19, 2009 @10:32PM (#27641337)

    Sunforce Air X Marine Wind Turbine 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.

    Indeed. I've overnighted in a 44' sailboat while anchored in 40 knot winds more times than I can count. Sometimes you just don't have a choice. Fun times. I call it vacation :-)

    The turbines work well and of course provide power in lower winds. It all adds up when charging batteries. Though they tend to be noisy, so we use solar on the boat. I really wouldn't want to listen to the turbine, whether night or day.

  • Design? (Score:3, Interesting)

    by mutantSushi ( 950662 ) on Sunday April 19, 2009 @10:43PM (#27641391)
    Larger rotor diameter generators obviously are advantageous. But this study/article seems to not acknowledge an interesting approach that was investigated in Britain: (In areas with sufficient regular wind), houses/buildings whose roof pitch is parallel to the common wind direction (i.e. the roof line is perpendicular to the common wind direction) can exploit their aerodynamic shape to boost the efficient of smaller wind rotors. With an additional "wing" form mounted above a row of smaller wind rotors (like a little roof), combing with the increased local wind speed generated by the roof pitch, the smaller rotors can easily achieve efficiencies of >2x the same size rotors not mounted to take advantage of local aerodynamics. This type of approach is of course generated at the site of usage, so has no transmission losses. Design doesn't matter?
  • by Anonymous Coward on Sunday April 19, 2009 @11:08PM (#27641529)

    No it doesn't have to use a lot of energy. Here in Finland we are beginning to build so called zero-energy houses, which use a very little energy for heating. The insulation is VERY thick, I think it's about 50cm atleast in the walls and more on the roof. My friends house (we live on the southern coast of Finland, winters usually range from 0 to -20 degrees celsius, but more is not totally uncommon), has 60 cm on the roof and has a ridiculously inexpensive electricity bill (both heating and lights etc.)of about 150 euros / month (1 kwh = roughly 10 cents (euro cents)) The house is about 300 square meters total and has three stories.

  • by Hadlock ( 143607 ) on Sunday April 19, 2009 @11:19PM (#27641595) Homepage Journal

    Not to mention the 24 MILLION people living in Texas, notably Dallas and Houston. Dallas is less than one degree north of Cairo, Egypt, and come June-September you wouldn't be at all surprised if one day you saw pyramids here. From June-September the temperature never, ever, ever drops below 84 degrees, even at night. Meaning that the houses get heat soaked and really you're just cooling the air inside the house - the walls and structure never get below 90 degrees. People set their AC at 78 degrees but even then all you're doing is removing some of the humidity and the AC kicks on every 10-15 minutes for 1/3rd of the year.
    Oklahoma is pretty much in the same situation but I heard only recently did major cities there start supplying their citizens with electricity and indoor plumbing :)

  • by fractoid ( 1076465 ) on Sunday April 19, 2009 @11:21PM (#27641615) Homepage
    We knew that larger windmills generated more power (duh), and that they had some advantages in efficiency etc. over small ones due to economy of scale. What wasn't completely obvious is that below a certain size, a windmill won't ever pay for its own manufacture, much less be at any sort of realistic advantage.
  • by fractoid ( 1076465 ) on Sunday April 19, 2009 @11:34PM (#27641669) Homepage
    You're modded funny, but a friend of mine has a family business making saddlery gear (horse saddles, riding gear, etc.)

    Guess where most of the riding crops they manufacture go? Not to riding schools, I can tell you.
  • by Anonymous Coward on Sunday April 19, 2009 @11:40PM (#27641713) []

    This will work is in faster and slower winds than your traditional propeller. It's silent and durable. Cheap and easy to install.

  • Re:While I agree... (Score:2, Interesting)

    by Tenebrousedge ( 1226584 ) <> on Monday April 20, 2009 @12:16AM (#27641859)

    Oh, wonderful! All of our problems are solved, at least until a couple centuries from now. Peak uranium chart, anyone?

    Let's not bank on solving the fusion puzzle. Yeah, it could happen and that would be great. I'd rather do a renewable energy source, thanks.

  • by Animats ( 122034 ) on Monday April 20, 2009 @02:05AM (#27642205) Homepage

    I went to a "Green Expo" last year, and saw one booth with a small windmill, with about a 2 meter diameter 3-blade carbon-fiber blade assembly. The blades were fixed, and there was no overspeed feathering/furling capability. This was $10,000. Using their numbers, payback time was a century.

    The going rate for a 2m turbine is about $1000. [] So I asked the sales rep why their unit was so expensive. He said "this is a status symbol, like a Mercedes". Right.

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

    by pfafrich ( 647460 ) < minus painter> on Monday April 20, 2009 @03:45AM (#27642661) Homepage
    Small wind-turbines have a very specific use, for mobile locations and other places which don't have access to the mains grid. You see these sort of turbines a lot on canal boats, caravans and other RV's. In such locations some power is better than no power. The cost-benefit analysis is considerably different, weight and portability of the device are important characteristics.

    For a couple of years, we ran a project [] completely off the grid, no electric, no gas, no water. Our power rig was a small wind turbine (about 1m diameter) a solar panel, and a bank of about 10 batteries. We also used 12 volt, low power equipment - specialised lighting 12 volt TV's etc. Heating was from wood, cooking from bottled gas. With this set-up our electricity use was small and I don't think we ever ran out of juice. Cost of the rig was small comparable with the £1000 it would have cost to get a mains hookup.

  • by Anarchitect_in_oz ( 771448 ) on Monday April 20, 2009 @04:05AM (#27642769)
    So the Skystream at 3.7m and 5 Euro/kWh produced enough energy to power 2/3 of an average house. So how close does that come to powering a full remote house who are use to being careful about power. So remote farmhouse in Australia where the neighbour aren't close enough to share a single tower it sounds like this might be an ideal product. Add say gas or good old plain timber burning to cover demand load like cooking and heating a small generator to cover shortfall or emergencies and you have a solution this product suits. Yes wind in built up areas isn't a solution. Yes small turbines when you have distribution density to work with ins't a solution. But doesn't mean these products are useless.
  • Re:Some thoughts (Score:5, Interesting)

    by MrKaos ( 858439 ) on Monday April 20, 2009 @04:21AM (#27642831) Journal
    Hi again Idiomatick, I hope you don't think I'm attacking you just because I addressed some of your other points in another post. I can see you are enthusiastic about Nuclear power but I think it's important to be pragmatic about it's application.

    Nuclear reactors will get more efficient.

    You have to remember that once a nuclear power plant is operational it is very hard to make it more efficient than it's design intends. In some cases attempting it has serious trade-off's. i.e. Running the fuel longer produces more radioactive spent fuel whilst using nano-technology to increase the heat carrying capacity of the primary coolant loop makes new (as yet unidentified) isotopes in the cooling water further complicating disposal.

    Comparing Nuclear to Wind: Nuclear converts heat to mechanical motion to electricity where-as wind converts mechanical motion to electricity. As discussed in the other post, wind also has a shorter technology development time between generations than nuclear. Implementation of the design improvements takes place at build time for a new nuclear plant, compared to at service time for an operational wind facility of similar capacity. Further, improvements to a wind generation facility can occur without taking the entire installation off-line.

    So yes, nuclear reactors will get more efficient, but so will wind. The difference is that the implementation of the design improvements for a wind facility can be implemented while a wind facility is still operational as opposed to a new build for a nuclear plant.

    They will be able to reuse their waste (already have that tech).

    We sorta have that tech. The main issue is (and most people are thinking of an IFR [] refering to this tech) is the reactivity of the sodium coolant increases the build costs and accident sequence precursors are not known, subsequently the lethality of an accident increases as the reactor ages. Furthermore the Pyroprocessing stage to produce (and recycle) the fuel for it doesn't exist.

    IFR is a good design though. If the coolant issues could be solved (like maybe using lead for a coolant) we would be one step closer. The remaining issues would be to have materials technology available so that the lifespan of the reactor could be made to match the waste (fissile ash) decay rate.

    And we will be able to find much more in the ground. Uranium is more common than tin. Enough to last 150years I'm sure.

    The issue here is that the amount of fissionable Uranium is a small fraction of the yield, that is much more U238 vs U235. Most of the easily mined 'soft-ore' uranium is gone. As most of our reactor technology is once-through we find we are in the same situation for uranium as we are for oil. If we increase our consumption, the day just comes sooner.

    By then we will have something way better.

    Hopefully some fusion reactors!!

    Gimping what is effective now for something that may happen in 100+ years from now is silly.

    It's important to spend time examining the supporting technology and infrastructure that is part of the ENTIRE nuclear process, including the political machinations that got us here. The toxicity of the mining process, heavily greenhouse gas producing enrichment process, reactors designed for 40 years only usable for roughly 3/4 of that time and no long term spent fuel containment plan are all issues that have to be resolved for any serious expansion of the nuclear industry to occur.

    The lions share of energy research funding, funding that could be used to DEVELOP alternatives, is currently spent on Nuclear power. Even doubling alternative energy research budgets would only take 1/7th of the current nuclear research budget. We could quadruple alternative energy funding and still have plenty of funding to resear

  • by Hadlock ( 143607 ) on Monday April 20, 2009 @04:47AM (#27642917) Homepage Journal

    And yet, the DFW area didn't have its population boom until the advent of AC... Not to mention any house built since 1960 (that would be 95%, possibly higher) were designed for closed window ventilation via AC. Not having air condtitioning working is a MAJOR emergency here come august, a house with closed windows and no ac can easily reach 95 degrees in August. Plus it takes several days to pump most of the heat out of the internal walls, furniture appliances etc. In other words its fucking miserable. Its possible to built another style house but I haven't seen one built here in ages.

  • by Dr. Hok ( 702268 ) on Monday April 20, 2009 @05:33AM (#27643135)

    Not to mention both dallas and houston sit on top of 50 ft of clay the consistency of partially frozen jello pudding.

    I am not a brick-maker, but this looks like an excellent resource to bake bricks. And it is, as you write, incredibly abundant. So it should be easy (and cheap) to build thick brick walls. My house has 24 cm (10 in) brick walls which provide a decent heat insulation. Not by today's German standards for new houses, of course, but well enough.

  • Simple (Score:2, Interesting)

    by rml1997 ( 929311 ) on Monday April 20, 2009 @08:08AM (#27643845)
    I'm an electronic engineer and I could have told you that the relationship between blade length and efficiency is non-linear. We learnt that at uni. People really need to get over their attitudes against the sight of large wind turbines. It is the only efficient way of doing this. Being a brit, large wind farms over here are a more difficult sell as we are quite limited for space, however several projects are being undertaken. In the states, you have the desert which seems a perfect area to locate your wind farms, dependant on wind levels. Get your hands off the oil :p
  • More errors (Score:3, Interesting)

    by Grismar ( 840501 ) on Monday April 20, 2009 @09:11AM (#27644459)

    I actually read a paper with the article in it, the Dutch Volkskrant carried 2 articles, one as local news and one in the science section.

    Both articles state that 3.8 meters per second on average is actually slightly LOWER than usual, not higher as the summary suggests. Since there is an inverse cubic relationship between wind speed and energy yield (i.e. halve the wind speed and only get an eighth in energy), it's not straightforward to say what the results would have been in a windy year.

    The articles state that the larger models are sufficiently efficient to make a profit over one or two decades, but that none of the tested models actually break even in terms of overall energy savings, considering the amount of energy required to produce the windmills. Personally, I think that's hard to say, since you would no longer be needing the alternative infrastructure, but that's what the authors stated.

    Also, note that this is news from a newspaper, not a scientific publication, so there might be some details missing that can really skew the results.

    Doesn't matter in this case though, since the summary can't even get the details that WERE provided right...

  • by Dr. Hok ( 702268 ) on Monday April 20, 2009 @09:40AM (#27644835)

    I watched a TV discussion about windmills in the German state of Brandenburg the other day. (FYI: Brandenburg is practically devoid of people but full of windmills.)

    The interesting thing was that someone spoke about prototypes of hybrid windmills with hydrogen storage, which were installed recently. He didn't elaborate further, but I guess they produce hydrogen through hydrolysis when the wind blows but the current is not being consumed, and convert it into electricity with a fuel cell when the current is needed, but there is no wind.

    IMHO these things can be the solution to the principal problem of wind power, namely that it blows when it wants to, not when it is needed. They can probably even be used to provide a decent base load, instead of requiring a base load provided by oil or coal plants.

  • by Hadlock ( 143607 ) on Monday April 20, 2009 @01:34PM (#27648745) Homepage Journal

    I think most of our brick comes by train from mexico, lumber from washington. Early settlers lived in log cabins, but if you look at the replica of the original cabin for Dallas tx that served as a trading post so many years ago the logs are only 6" in diameter at best. Dallas is full of 20' shrubby looking oaks but you have to drive to Tyler, tx to see a tree you could begin to cut a single 2"x12' from. Most houses in north dallas are timber framed with brick walls for looks. At least 30% of homes in dallas still have single pane windows wtf.

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