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12 Small Windmills Put To the Test In Holland
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."
rather than 141, if you used the Montana.
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.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
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.
Apparently it does matter, and these were obviously very poorly designed if three of them straight up broke.
3.8 meters/second average is not a windy area, infact it's a Class 1 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.
... What will they think of next?
But the electricity needed to power the average American household would power a medium-sized Dutch city, right?
Get your own free personal location tracker
Why don't the Dutch install tidal turbines in their fields instead, and wait for their country to flood.
Oh I kid, I kid
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.
You are not entitled to your opinion. You are entitled to your informed opinion. -- Harlan Ellison
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.
GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
[...]and only windy areas will benefit from them.
Well I'm glad we finally cleared that up.
Maybee zie posteer kann no sprechen oder reeden die Dutchenzeelandspache so gut.
And it had 5 meter blades, which are way to big for the average rooftop.
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.
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:
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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
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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.
Life is a great ride, the vehicle doesn't matter
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).
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.
[b.belong('us') for b in bases if b.owner() == 'you']
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.
"I assumed blithely that there were no elves out there in the darkness"
windspeed cubed and radius squared
not to mention the effect of turbulance on o/p
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).
[b.belong('us') for b in bases if b.owner() == 'you']
Dutch experiment proves theory doesn't map to practice. Film at 11 ...
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
This has to be the worst summary ever. Please take the time to look at the article and do the maths yourself.
"Some days even my lucky rocketship underpants don't help."
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.
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.
I prefer the "u" in honour as it seems to be missing these days.
"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.
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
On the Renewable Energy website OliNo there is an article Test results small wind turbines 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, 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.
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.
Knowledge is power. Knowledge shared is power lost.
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.
Misschien kan de man niet Nederlands heel goed spreken of lezen?
If this is real... then its real cool.
;)
http://www.youtube.com/watch?v=RRXRUFrxKAQ&feature=related
I know that where I live, if I had one of those, I wouldn't need to be plugged into the grid (most of the time at least.)
And there are so many other hobbyists who have vawts on youtube - interesting stuff. The dutch just took the wrong approach to it
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.
Producing Transportation Fuels with Less Work
Diane Hildebrandt,1 David Glasser,1 Brendon Hausberger,1 Bilal Patel,1 Benjamin J. Glasser2
The long-term strategy for reducing emissions of carbon dioxide (CO2) and other greenhouse gases is to replace fossil fuels with renewable resources. In the short term, liquids derived from fossil resources will be used to power transportation, in part because liquid fuels have an established production and delivery infrastructure as well as high energy density. Liquid fuels are overwhelmingly derived from increasingly scarce crude oil, and it would thus be beneficial to make liquid fuels from other sources, such as coal and biomass (1, 2).
One reason why liquid transportation fuels are derived from petroleum instead of coal is that converting coal into liquids is much more energy-intensive. Thus, substantially less CO2 is released in the production of a gallon of gasoline derived from petroleum than in the production of fuel from coal-to-liquids (CTL) processes (1). The carbon atoms in coal are largely bonded to one another in graphitic networks, and breaking these bonds requires a large energy input. Energy is also needed to supply hydrogen to the process. We outline reaction chemistry and processing designs that could dramatically reduce these energy inputs and minimize the amount of CO2 emissions that would be emitted or mitigated by other costly strategies, such as carbon capture and sequestration (3).
There are many methods that convert carbon-rich sources into liquid fuels, including pyrolysis, direct liquefaction, and indirect liquefaction, which proceeds through gasification such as the Fischer-Tropsch (FT) and methanol-to-olefins (MTO) processes (2, 4). Of these, the FT process
3C + 4H2O -> 2CO + 4H2 + CO2 -> 2(-CH2-) + 2H2O + CO (1)
(where CO is carbon monoxide and -CH2- represents the alkane products) has been successfully implemented on the largest scale industrially (2, 5) but is very inefficient in that a large part of the carbon fed into the process ends up as CO2, either directly or indirectly from fuel consumption for heating the reaction (5). However, FT technology gasifies the coal so that unwanted ash, heavy metals, and sulfur can be removed (2).
To identify more efficient ways to run chemical processes, theoretical tools have been developed that can look at the industrial plant as a whole (6-9), even at the level of rethinking the reaction chemistry. These tools assess what would happen if we could operate the plant as efficiently as possible (that is, near thermodynamic reversibility).
For example, thermodynamic principles have been applied to examine the production of molecular hydrogen (H2) by thermochemical cycles (6). By analyzing reversible processes, limits can be placed on the best performance that can be achieved for a given cycle. For example, H2 could be produced through chemical reactions powered directly by the heat from a nuclear reactor, such as zinc reacting with water to produce zinc oxide and H2. The zinc is recovered by heat-driven decomposition of zinc oxide. A thermodynamic analysis has shown that the currently proposed thermochemical cycles for producing H2 cannot compete with electrolysis of water through direct use of electricity (6).
Thermodynamic analysis of reversible processes can be coupled with theoretical efficiencies to allow comparison of real processes. Such an analysis was performed for direct H2 use for transportation, and the findings were compared with other strategies for reducing greenhouse emissions and U.S. oil imports (6, 10). This work has brought to light serious concerns about the feasibility of an H2 economy.
However, recent work suggests a path forward for the sustainable production of liquid hydrocarbon fuel for transportation that would make use of H2 produced from carbon-free energy, such as solar or wind (1, 11). These processes add H2 to the syngas (CO and H2) produced from gasification of biomass, a
No one in the industry I am aware of would say one of those tiny (those montana and skystream models are the exception there, as they are more realistically sized) windchargers would power a household. And further, no one credible who sells or installs realistically sized residential windchargers would recommend it be installed on a household roof. I have a very small windcharger, 300 watts max output in ideal conditions, it is designed to provide a small amount of battery recharging capability for like sailboats or a small weekend cabin or something, and that's it. Same as no one solar panel is going to power your home. This is the duh part, I mean, read the dang specs before you buy and try to keep in mind what your demand would be. There are still a lot of decent windchargers out there that fall between these tiny models and those megawatt sized hugemongous models.
This was sort of a *really* stupid test. Might as well throw a lawnmower engine in your caddy to try and achieve epic mileage, and then see how far you get down the road. It is that dumb to anyone who knows anything about alternative energy.
There are tens of thousands of people who own and use residential windchargers, all over the planet, but they are all designed for the task, they are all large, and mounted on sturdy tall towers. The mentioned two largest ones there should be considered entry level in size for practical household use. Yes, size matters obviously, and this info has been out there for close to a century now as regards wind to electrical power.
Yeah, I try to keep up with this stuff, since I live in a location that has an "above average wind energy density" to put it mildly. Just last week I saw a hyped article about a new small turbine, went to their web site, and they're claiming that their device only costs about $5,000 installed and will generate 500kWh/year. I blinked. I re-read. I went to other pages to see if that figure was a typo or consistently used. But nope, that's what they're claiming: for only $5,000 up-front I can generate $50/year worth of electricity. And to think, some of the founders will probably be surprised when the company is out of business in a very few years.
So, obviously, I thought that it was ridiculous (and sad) that a company would offer such a low-producing product at that price. But looking at these test results, $5,000 for 500kWh/year is actually hugely better than most!
2 to power an average Dutch home, an American home takes on average 3 times more energy. Important bit in TFA: the 18-meter windmill nearby only cost about 20% more than the combined cost of all the small windmills, yet it produces 20 TIMES the power.
You really should check things like article links more carefully if you want to quibble about "news" versus "discussion." The summary link: http://www.lowtechmagazine.com/2009/04/small-windmills-test-results.html, astonishingly is to a "journal." It is the author of the journal article that asserts that "small" windmills "are a swindle." The references to "design" by the OP also appear to derive from an uncited link: http://www.lowtechmagazine.com/2008/09/urban-windmills.html, to another journal article that debunked small windmills as a poor investment, or as the authors of the linked article put it "fundamentally flawed." There is in fact apparently nothing in the summary by the OP that does not appear to derive from a "journal" source, if you consider that important. So, evidently it really IS news, wouldn't you say?
------ The only greater hazard to your liberty than n politicians is n+1 politicians.
Tall buildings and skyscrapers are a boring part of the city scape. Nothing ever moves. They are only pretty with Christmas lights.
I suggest Turning the Burj Dubai building into not only the world's tallest building, but also the world's largest windmill. At that height, one swing should power the whole world for the year!
Sure, we're not all US, but US households are becoming a de-facto benchmark because they're the biggest consumers of energy on a per-household (or per-capita) basis.
Actually they are not. In Canada we have a bigger household energy consumption than the US but this is due to heating. When it the winter lasts 6 months and temperatures drop to -40C heating tends to use a lot of energy no matter how efficient your home's insultation is.
Dutch province of Zeeland
There is your answer.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
When did you sell your tulips?
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I only took one season of Benny Hill German in high school. My apologies to the Dutch.
I thought all your hippy orgies in your communes would keep you warm you socailists.
An Education is the Font of All Liberty
You want to look at price per kwh. According to this overview, average price per kwh in The Netherlands is 0.28 per kwh. The Skystream is the most efficient generator per kwh at 5.09 EUR.
Without discounting to present value or accounting for inflation or other possible future taxes, you need 18 years of flawless operation to break even.
Read what I mean, not what I wrote.
Having grown up in a household whose total electrical needs were powered by a single 3m wind generator, I'm finding this article summary awfully amusing.
But what sort of idiot puts a windmill on a roof? There are so many things wrong with that.
1) A roof is way too low. The optimum height, in terms of tower cost versus power value, for a turbine of scale sufficient to power a household is generally at least a hundred feet, and preferably notably more. Wind roughly follows a so-called "1/7ths power law", so those first hundred or two feet up make a huge difference. After that, it's a case of diminishing returns.
2) A roof is high turbulence. Turbulence is very bad for wind turbines -- robs them of powers and stresses their hardware. You want to be well above sources of turbulence.
3) A roof is generally not nearly strong enough, and would have to be reinforced anyway.
4) They weren't even bothering to test on a roof in their study.
One thing this article left out was the tower. That may seem like a trivial thing to most people here, but it's not in the least. I made a spreadsheet to crunch the numbers when I was looking into wind power. I found that it actually can be approximately breakeven where I live (in Iowa) if you're out in the countryside so that you can build a very tall tower, and you use a guyed tower**, and you can get a good deal on the tower, and you're grid connected so you don't have to deal with power storage, and you're not an idiot when it comes to turbine selection. Yeah, a lot of "Ifs". But regardless, the tower generally makes up 50-75% of your total costs in a properly designed home-scale system (20-25%-ish on a commercial-scale system).
"You see, Government is a system that is based on weapons." -- Timster
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?
Wow, reading more I see how blatantly WRONG this summary is.
1. You RTFA
2. You assume the summary is right
What's wrong with you?
Yeh, the summary seems to reek of anti-green, or at least anti-wind technology. The assertion that 141 are required assumes that you are using the worst windmills in the US. A clear sign the submitter is not only anti-alternative energy, but also an obnoxious American.
Actually, it reeks of anti-"I'm a trendpoppet with a micro windmill on my roof so I can preach to you about how holy I am by using recycled toilet paper". They seem to me to be just saying "yeah, these small windmills really really suck compared to just having one big windmill powering a bunch of homes".
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
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.
IIRC, power output increase as the cube of windspeed and the square of surface area. Might have those mixed up. But in either case, no, power output does not scale linearly.
-b
No offense, but I've stopped responding to AC's.
With all these propellers spinning, don't they make the earth rotate faster?
I am anarch of all I survey.
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.
Maybe you don't have the energy requirements of an "average American household". Try adding 4 televisions, three large fridges, two air conditioners per apartment and you'll be halfway there.
Yeah! And we all drive three SUVs at the same time, to maximize our baby-seal-running-over potential.
However, when I hear that many houses in places like California still use antiquated buliding techniques/materials like single-pane windows I wonder how much of that air conditioning is actually neccessary. Double-pane isolated windows and a layer of mineral wool between the facade and the space inside the house could at least increase the effectiveness of the A/C, making you require less of it, thus saving energy. The best part is that there are no upkeep costs as long as you don't go around breaking your windows.
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
The cheapest turbine they have is 4300 euros. This is ridiculously high price. In Finland, you get a 2.1m diameter rotor for less than 1000 euros (controller, mast, turbine), and a full kits with batteries, inverter and solar panels for 1400-2500 euros. A 3.2m diameter turbine here costs around 4000 euros and 8m diameter turbine around 20k-30k depending on configuration. These are list consumer prices including taxes. The prices quoted in the Dutch "test" seem to around 4 times what you pay here!
The quoted average wind of 3.8m/s seems inland wind speed. It is quite obvious that there is no point in installing turbines in locations where the average wind speed is low, but they seem to get some power from the larger turbines, though the price level they have kills the payback times.
They correctly point out that taller mast makes a difference, but one point for large industrial turbines is ignored - industrial turbines do need a grid to deliver the energy. For small turbines, the idea is to use the energy where it is produced, avoiding cost of grid. Grid cost in Finland is around half of the the bill, and taxes around 30%. We have grid/transmission cost separately priced so you can select to buy renewable-only energy from grid).
They did figure out, which I assume most people in industry already know, that the diameter is the interesting factor. The power generated is in relative to diameter and square of wind speed and efficiency factor. There are lots of snake oil companies out there claiming bogus production numbers, which is unfortunate as it spoils the reputation of good idea. There can be easily spotted by calculating a wind area covered by the turbine and dividing that by price. As getting efficiency up by few percent tends to be very expensive, it is easier to just make simple blades few percent longer. The cheapest wind turbines sold here have continuous profile blades, and they still perform nicely, even though the center part of the turbine probably does not do much work.
We have 2.7m diameter unit (www.tuulivoimala.com, 500W nominal) at our vacation home we use in summertime. This is very non-optimal location, only northern winds and too much shadow for solar, so we took more diameter and big battery pack to offset non-windy periods. We use the power for lights, computers, 3g WLAN access point for network. Total cost of all electrical installation including lights, wiring, 2kW inverter, 980Ah battery pack, was less than getting grid to the place. Not enough for heating, but we burn wood for that, the plot is large enough to provide us practically unlimited supply of firewood. The power has been plentiful for our use. Electric chainsaw works for chopping the firewood, though we need to avoid continuously sawing more than 1 hour to avoid emptying the battery pack more than third :)
If you do not have a grid connection, the install cost of it will offset quite a big turbine and solar installation, so small turbines are very popular in vacation homes. And for vacation home, the more remote the better. Which means very expensive or impossible grid connectivity. In Scandinavia, solar does not work early spring or late fall, so wind turbine here may be the only option if you need electricity off-summer times. Combining solar and small wind turbine makes a lot of sense as the electrical installation is similar.
The same thing applies to developing countries. It often makes more sense to go directly to renewables than build grid to every small village. In south solar power or hybrid solar-wind is probably more dominant.
They claim that turbine does not even make up the energy used in making it. This is true only if the turbine is located in a low-wind location, or it is faulty design (no diameter!). I agree fully that it does not make sense to install turbines in city areas where buildings mess up wind flows. The location has to be one with good wind conditions.
To
The reported average wind speed seems rather slow, for that area. The average wind speed is normally more like 6 m/s. Here' s a wind speed map of the Netherlands: http://www.gewiekste.nl/wdk.jpg.
assignment != equality != identity
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
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...
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.
Say out loud: I'm an Aspie and I'm somewhat proud, I guess. Uh. Can I write an email in all caps instead? Hm...
If pictures of dead or dying kids will not get the anti-vaccine people to change their minds then I doubt simply seeing a windmill will get those who dislike them to change their minds. Most people really hate admitting a mistake.
The trick to that is putting a vapor barrier only on the in side of the wall. That allows the out side to breathe (and vent excess moisture), preventing mold buildup inside the wall, and if the wall is sufficiently insulated, the inside will not get cold enough for condensation to form -- provided you don't have cool, moist air inside the rooms (which is a problem my grandparents faced in far corners of the house). Air circulation helps by replacing cool and moist air with warm and dryer air. Even internal circulation will help greatly, though getting rid of excess moisture by venting outside (through a vent or imperfect walls) is best.
Be relentless!