Talk:Wind power/Archive 3

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Where did the formula come from?

It is really necessary to give a citation for the formula for power generated by a wind turbine. We need to knw if the information on wikipedia pages are reliable - particularly something so fundemental. —Preceding unsigned comment added by 77.96.122.250 (talk • contribs) 22:34, 18 November 2007

It's pretty basic physics, 1/2 mv^2, with density times area times velocity giving the mass flow rate, but I've added a ref.--agr (talk) 22:52, 18 November 2007 (UTC)

For those who don't know much physics, 1/2 mv^2 (also written as 0.5 x m x v x v) is the kinetic energy of a particle (for example, a molecule in air) of mass m travelling at a speed v. There may be a simpler, or more intuitive, way to present the available power. Ga2re2t (talk) 16:57, 19 November 2007 (UTC)

In the example given for mass flow, I belive that it comes out to about 300,000 kilograms of air per second, not 77,000. 1.225 kg/m³ times π(100)² m² times 8 m/s = 98000π kg/s ≈ 307876.08 kg/s —Preceding unsigned comment added by 209.162.55.19 (talk • contribs) 19:00, 2 December 2007

No, it's correct. 100 is the diameter in meters. The radius is half that, 50 meters. 1.225 kg/m³ times π(50)² m² times 8 m/s = 76969 kg/s. --agr 19:43, 2 December 2007 (UTC)

Hmmm, this section on potential wind power does not seem consistent. The available wind power formula probably should not contain the efficiency parameter (alpha). A second formula (extracted wind power?) should include this formula. Something like:

$P_{E}=\alpha P_{A}$

Or, the remark that "The power of the example breeze above through the example rotor would be about 2.5 megawatts." should be modified or removed as it does not take the efficiency into account. Assuming that the maximum power is extracted then according to Betz's law we should have:

$P_{E}=59\%\times 2.5=1.475$  Megawatts

On a sidenote, is using Greek characters necessary? I know this is the way science would present it, but Wikipedia is for the general public, many of whom may not be comfortable with algebraic expressions, particularly those in the Greek alphabet. I imagine that many people do not know that rho refers to $\rho$. Ga2re2t 18:45, 4 December 2007 (UTC)

I've tried to address your concerns. I haven't removed the Greek letters, but have incorporated them in the body of the text, rather than using their names.--agr 19:20, 4 December 2007 (UTC)

Thanks, nice job. I think those changes really make a difference. If any part of the article needs to be clear and consistent it's that part, as I would imagine that it is one of the principal pieces of information that people look for. Ga2re2t 21:08, 4 December 2007 (UTC)

World windpower map

I found this map interesting [1]. Maybe someone who understands German can decide if it is copyrighted? More graphs here [2]. Ultramarine 18:13, 26 Apr 2005 (UTC)

The USA map should anyway be taken off. This article is not about Wind power in the United States! deeptrivia (talk) 00:48, 4 January 2006 (UTC)

A worldwide wind power map would be good, but would lose a lot of detail. The US map is the best freely available example I've seen, but I'd be happy to see something better. Iain McClatchie 19:21, 4 January 2006 (UTC)

The map indicated by Ultramarine [3] is from a speech by Gregor Czisch for the conference "Wind Power for the 21 Century" held in Kassel, Germany, 25 Sept. 2000. It is a map of potential wind energy given in full load hours FLH of 1.5 MW plants (thus 1 FLH = 1.5 MWh per year). (All this is mentioned on the site in english). As far as I can see there is no copyright on the map or the slides. However, the map does not take into account that not every location is actually suitable for a wind power plant. It is however a good overview of where attractive sites would be located.--83.76.170.90 02:27, 4 September 2007 (UTC)

No copyright notice does not imply no copyright. Does German law/treaties include copyright upon creation? (SEWilco 04:15, 4 September 2007 (UTC))

Energy Audit of wind turbines.

Discussions as to whether or not wind power is a net energy producer over its lifecycle. It was pointed out that energy costs are incorporated into the cost of any product and are generally a relatively small amount of the cost of a product so that it was unlikely that wind power is a net energy sink. A reference was eventually obtained: "[[4]] addresses this question. You'll all be relieved to know that the example wind installations produced between 17 and 39 times as much energy as it took to build and run them. --Wtshymanski 17:37, 10 August 2005 (UTC)"

Opposition POV's: Ecological disaster / global warming.

Discussion took place as to whether consuming wind energy would interfere with heat transport in the atmosphere.

Per Earth's_energy_budget the solar radiation input number you're looking for is 174,000 TW (Terawatts), 70% of which is absorbed, 64% by the atmosphere, so about 111,360 TW is tied up in the atmosphere at any given moment. For comparison, our Fossil Fuel consumption is about 13TW, all of which is human added waste heat. We don't require that much electric energy, total global grid consumption is about 1.5 TW (mostly from coal and ng which are included in the FF figure). So replacing FF derived grid power with renew/systain-ables (wind, etc), and the remaining ineffecient transportation (~20% usefull work done) use of FF with more effecient transportation methods (EV and BEV) would reduce that energy requirement substantially. This transportation transition may require the doubeling of grid capacity to 3 TW (my rough estimate). So it might prove to help! Eliminating 13 TW of excess heat and instead obsorbing 3 TW of said excess energy (though I doubt it would work out so elegantly). Anyway, that 3 TW represents some 1/37120th or 0.00269% of the energy in the atmosphere. Of course I could be offbase and am no expert myself. --D0li0 22:49, 17 September 2005 (UTC)

I've removed the paragraph that claimed the mechanical energy extracted from wind has any effect on global warming - as the above discusion also shows, when you're dealing with order of magnitude of 10^17 watts of insolation, total world electrical demand even at 5000 watts/person is on the order of 10^15 watts - lost in the noise. Also, don't forget that (aside from freaky exceptions like power beamed into space, stray light lost by streetlights, and energy bound up in reducing chemicals electrolytically), generally speaking, a kwh of electricity generated turns into heat in the atmosphere anyway. The only offset is that wind generated power offsets CO2 accumulation - insofar as that affects climate, that would be the only "global warming" benefit. --Wtshymanski 17:50, 4 April 2006 (UTC)

10^15? 5,000 watts/person x 6.5 billion people/planet gives about 3x10^13 watts/planet. pstudier 21:53, 5 April 2006 (UTC)

Shaping

We need some good sources on "shaping," which I understand to mean back-up power for calm wind periods. I've read that when hydropower is used to shape electric power on a grid, the price increase amounts to 20%. This seems somewhat at odds with a rule of thumb estimate mentioned that no more than 1/3rd power on a grid should be wind. What is the actual premium involved in shaping wind power on a large (e.g. North American) grid?

see http://en.wikipedia.org/wiki/National_Grid_UK#TriadsEngineman 19:03, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/Spark_spread#Clean_spreadEngineman 19:04, 11 November 2006 (UTC)

http://en.wikipedia.org/wiki/National_Grid_%28UK%29Engineman 19:07, 11 November 2006 (UTC)

What is the actual proportion of wind power beyond which shaping is inadequate for reliability? --James P.S. 07:04, 23 December 2005 (UTC)

Pjmaker 01:26, 28 January 2007 (UTC) writes:

Based on real systems typical wind penetrations (percentage of wind power out of total system load) figures for isolated wind/diesel/gas turbine systems in Australia (x5), Antarctica (x1) and the Azores (x2) are in the range 55% up to 93% depending on the configuration. These figures are for maximum wind penetration when the wind is available. These systems all operate with full backup, i.e. loss of the wind turbines should not disturb the grid. To quote from: http://www.horizonpower.com.au/environment/renewable_energy/wind/wind_hopetoun.html

"The wind turbine is expected to supply approximately 42% of the town's electricity requirements per annum. Instantaneous wind energy penetration of over 90% has been achieved. The Hopetoun wind/diesel system is expected to save approximately 400,000 litres of fuel annually."

The Esperance Wind/Gas systems which is about a 15MW grid gets figures like:

"The wind farms generate about 22% of Esperance's electricity. Maximum instantaneous penetration is just over 65%."

The 65% is what you get overnight at low system loads when there is enough wind.

You might also like to look at http://www.aad.gov.au/mawson for real time data from Mawson in Antarctica which is really remote system. Pjmaker 01:26, 28 January 2007 (UTC)

Least expensive form of new power

I've read from the Rocky Mountain News that wind power is the least expensive form of new power, recently dipping below the per-kwh cost of coal. Does anyone dispute this? --James P.S. 07:04, 23 December 2005 (UTC)

The "Rocky Mountain News" article is suspect. It says For instance, the construction cost of a conventional coal-fired plant is about $1,000 for every kilowatt-hour of electricity it produces. Cost of a wind power plant is $900 per kilowatt-hour, nuclear is $1,700 per kilowatt-hour while solar thermal is $2,400 per kilowatt-hour. In contrast, the cost is much lower at $400 per kilowatt-hour for a natural gas-fired plant, according to the Energy Information Administration. Evidently journalists writing about energy don't know the difference between a kilowatthour and a kilowatt. Look at your own electrical bill and work out your cost per kilowatthour and you'll see the problem immediately - these prices are about 4 decimal orders of magnitude too high. Assuming our innumerate source meant that the capital cost is in dollars per kilowatt (not kilowatt-hour), then consider that a wind plant doesn't produce nameplate kw all year - this means the capital cost is more like $2,058 dollars for a kilowatt with the same load factor as a nuclear plant. I've deleted this reference yet again - cost per kw is only one of the costs per kwh. --Wtshymanski 14:18, 6 February 2006 (UTC)

The simple and obvious typo you are referring to -- using "kwh" for "kw" in the construction cost doesn't disqualify the cost per kwh table at the end of the article, which is in line with other sources. Moreover, the statement that coal is still less expensive is misleading because only the oldest grandfathered-exempt coal plants are. --James S. 01:23, 7 February 2006 (UTC)

It's not a single typo, it shows a complete lack of understanding of the cost of electricity generation - this consistent error makes me doubt the accuracy of the whole article. It's not much help quoting articles that require a subscription to access. I'd like to see an article quoted that had some internal consistency and credibilty -journalists are notoriously inaccurate at numbers. --Wtshymanski 00:13, 8 February 2006 (UTC)

Sorry, which one takes a subscription? I can see them all and I don't think I have a sub to anything here. --James S. 03:15, 8 February 2006 (UTC)

Coverage stats

I've calculated that the U.S. could serve 95% of its electrical demand (again, with grid shaping based on hydropower) with wind turbines on less than 3% of U.S. farmland. Does anyone want to challenge this assertion before I add it to the article? --James P.S. 07:04, 23 December 2005 (UTC)

Why not just use the exisitng power stations to take over when its not windy - it usually windy somewhere?Engineman 18:37, 11 November 2006 (UTC)

see http://en.wikipedia.org/wiki/National_Grid_UK#TriadsEngineman 19:03, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/Spark_spread#Clean_spreadEngineman 19:04, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/National_Grid_%28UK%29

How did you determine this?

I first got the area of farmland from the CIA Factbook or something. I then went to www.windpower.org FAQ and looked up the power density per area for new installations. Then I found some PDF from the Electric Power Research Institute to get US demand. I came up with a quotient of 1.2% IIRC, then I used some extreme shaping and grid capacity assumptions to round up to 3%. Please check my work. —James S. 21:52, 4 January 2006 (UTC)

Did you calculate how much acreage is needed for the pumped storage? Are you proposing to use existing dams in your equation, and finally at what point do we cross the line into Original Research here? I do believe the 3% number is the one occasionally throw around - specious though in a sense because wind towers don't really occupy the land, you can continue to farm the land with or without. Another approach to shaping is demand shaping - rather than supply increasing. Having a significant portion of the load prioritized can mitigate entirely the issue of fluctuating supply. Generally heaters are used, cooling ice can be used, etc ... obviously both will be used. Benjamin Gatti 21:31, 8 January 2006 (UTC)

James - I think, at first reading, your calculations, whilst possibly numerically accurate, are worthless because they do not take into account the (huge) transmission links (and their associated costs) that would be needed to make such a scheme work. Basically the pumped storage is in a different place to the wind which is in a different place to the load (cities). Bear in mind that 400/500 kV transmission links (double circuit, around 2 GW per circuit) cost around $1M per km or around $1.5M per mile - you'd need 1000's of miles of such lines in the US I reckon. --Apower 11:34, 25 January 2006 (UTC)

I have worked in the power industry for many years in the UK, and for many years in the field of intermittent power generation (wind et al). Can people with no detailed knowledge of power systems and their operation please stop contributing well-meaning nonsense? E.g. comment concerning "maintaining a.c. phase" which I'm just about to remove. Any half decent power engineer knows the phase difference across a transmission line is (approximately) proportional to the real power transmitted and is NOT constant across the system - if it were no power would flow! Generation is made equal to demand on a continuous basis by maintaining constant frequency - any visit to a control room will demonstrate this. --Apower 17:40, 10 January 2006 (UTC)User:apower 17:40, 10 January 2006 (UTC)

How about in the UK where Reserve Service is triggered by a fall in frequency? Engineman 19:13, 11 November 2006 (UTC) see http://en.wikipedia.org/wiki/National_Grid_UK#TriadsEngineman 19:03, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/Spark_spread#Clean_spreadEngineman 19:04, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/National_Grid_%28UK%29

In direct response to the original question, the most succinct answer I know is this, from the UK:

“The analysis suggests that:

– costs are negligible at low levels, indeed small amounts of intermittent generation cannot be detected by the system operator;

– costs are less than 0.1p/kWh for 10% of electricity from intermittents;

– costs are less than 0.2p/kWh for 20% of electricity from intermittents.”

Source: Cabinet Office, Performance and Innovation Unit, 2002, “The Energy Review” (full report can be found here: http://www.strategy.gov.uk/downloads/su/energy/TheEnergyReview.pdf - see page 100). These are costs per kWh generated by wind.

Quite where the figure of a 20% increase in cost comes from I don't know - 0.1p/kWh is around 2-4% of the current cost of wind power. I am especially surprised as hydro would be the cheapest form of balancing power available, and is generally viewed as an excellent complement to variable sources like wind.

In answer to the question of an 'upper limit' - at the moment there is no proof of a technical upper limit to the penetration of variable power sources like wind on power systems, the issues are more economic and regulatory. Regions such as western Denmark and parts of northern Germany gain a quarter or more of their overall power from wind, and at times have been running on 100% wind; there has yet to be a power cut in these areas caused by wind variability. Danish grid company Energinet is relaxed about further wind development in the country, though northern German grid co Eon Netz is more hostile (but then it's dealing within a balancing market environment that is stacked against wind). These regions are highly interconnected with the European power grid (particularly Denmark with Norway and its hydro-dominated generation system), which certainly helps, but these real-life examples show that high penetrations are possible.

Re the relative cost of wind and other power sources - it really depends on the site: for instance, in New Zealand, which has possibly the best wind resources in the world, wind slugs it out with all-comers, with no subsidies bar a small uplift from selling carbon reduction credits; Germany is still handing out about 8€¢/kWh fixed for 20 years because its wind resource is terrible. The cheaper-than-coal line is almost certainly true in the US, however, if it factors in the effect of the currently in force Production Tax Credit, worth 1.9¢/kWh. The effect of this benefit is to make the wind market in the US go bananas - 2,500MW of new wind power went in last year, roughly 5% of the total installed wind capacity in the world.

Gordon Edge

[Declaration of interest/expertise: I work for the British Wind Energy Association.] 82.138.219.238 21:52, 13 January 2006 (UTC)

Gordon, I'm not arguing with you (really!) but figures like "Denmark produces over 25% of its power (energy) from wind" are grossly misleading when applied to arguments over the maximum penetration into a power system. Denmark (and Germany) is connected to, and is part of, the VAST UCPTE power system. Your comment "These regions are highly interconnected with the European power grid (particularly Denmark with Norway and its hydro-dominated generation system), which certainly helps" made me chuckle as it's like saying the invention of the Saturn 5 rocket "helped" with the moon landings. The proportion of wind energy on this (UCPTE) system is very small (I'd guess <2% without looking the figures up) which is why it's not a problem. I should declare I'm ex-National Grid, UK. --Apower 13:36, 20 January 2006 (UTC)

Hi Apower - thats a good point but a little unfair. If wind were added in the same proportion as Denmark across the entire UCPTE area, this would still be readilly absorbed, becasue the agregate variation would be very slight.... dispersed wind power sites are not stronly correlated.

see http://en.wikipedia.org/wiki/National_Grid_UK#TriadsEngineman 19:03, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/Spark_spread#Clean_spreadEngineman 19:04, 11 November 2006 (UTC)

and http://en.wikipedia.org/wiki/National_Grid_%28UK%29

Engineman 19:13, 11 November 2006 (UTC)

The claim of "40% penetration" in Denmark is like saying "100%" in Altamont, California. The ability of any of these countries to get 20% (let alone higher) is completely contingent on the UCPTE area wide grid, and, most notably, the existence of the French nuclear grid as the anchor for the whole thing. Seems that wind and nuclear work well together, oui?

DavidMIA 20:10, 8 May 2007 (UTC)DavidMIA

i hesitate to stick my nose in here, i am a complete noob to this article and have no directly relevant qualifications, but i would like to point people towards WP:No_original_research. I have seen a few sceptics on this talk page, and whilst i have an unhealthy WP:NPOV, myself towards wind power, i am an advocate -- i would encourage everybody to work towards an article, and by association and eventual subsequent hard work dependant articles in this topic that can all stand against the sceptics, and play a potentially valuable advocacy role by resting firmly on the WP:Five Pillars. (Elephants and turtle cosmology is optional.) David Woodward (talk) 16:46, 17 November 2007 (UTC)

Small residential wind turbine

Our new editor (who I reverted, but promised to look into his/her edits) quoted directly from [5] "Over its life, a small residential wind turbine can offset approximately 1.2 tons of air pollutants and 200 tons of greenhouse gases (carbon dioxide and other gases which cause climate change)." So we have notable facts and a reputable source, does this fit into the article? Simesa 22:07, 30 April 2007 (UTC)

Yes. --Skyemoor 01:25, 1 May 2007 (UTC)

External wind energy resources

I hope you find the following links useful.

• 3D wind power models - Google SketchUp
• Latest Wind power news - Feedburner
• Wind power directory - Energy Planet
• Wind power videos - YouTube —The preceding unsigned comment was added by Alex Ramon (talk • contribs) 11:16, 15 May 2007 (UTC).

The fact that you added these to 15 or so pages constitutes WP:SPAM. YouTube and newsy sites are not appropriate anyway. Cheers Geologyguy 13:24, 15 May 2007 (UTC)

Wing Energy Density of the U.S.

Does anyone know of a source that could cite the wind energy density of the United States? Estimates are given for other countries in the article, but I didn't see them for the US. All that is stated was that it was possible for the of 3 states to produce enough power for the entire country. Though, reading the source doesn't appear to be cited and doesn't specify whether the study was referring to just electrical or energy total consumption.

Also, I removed the italics from the word "theoretical" in the Theoretical Potential section. It was already made clear that the numbers were estimates through the title of the section/wording, and it was the only place the word was italicized in the article.

130.134.81.16 16:24, 13 July 2007 (UTC)

Why is wind direction important?

In the Turbine placement section, it says that it is important to know wind speed and direction. The need for wind speed data is obvious, but why is direction so important? Aren't all turbines able to pivot 360 and weathervane into the wind no matter what direction it's coming from? -- RoySmith (talk) 19:13, 29 July 2007 (UTC)

Oh, never mind, I see where it's discussed. -- RoySmith (talk) 19:18, 29 July 2007 (UTC)

Intermittency and distributed wind generation

If you have wind turbines 1000 miles apart feeding a single grid, are some of the intermittency effects likely to only cause times of low wind at one of the sites at a time? Obviously the warmest-days-have-low-wind effect may be likely to affect both sites to some extent, but those days are also predictable, and power plant operators can start up coal or nuclear plants for those days.

There needs to be some background info that needs to go along with any answer to this question. Any resources, no matter what the fuel type, that are 1000 miles apart will have practically no interaction with each other if both connected to an interconnected power grid with other resources. Just because they are on a single grid does not mean the will equally serve the same load. Power can flow long distances over interconnected transmission lines, but there are technical issues to overcome. First is losses, the longer the power has to travel, the more of the generator output is eaten up in resistive losses in the conductor. Second is voltage support, the higher the power transfer and the longer the distance, the more reactive support is needed to maintain adequate voltage to transfer the power. Also, starting up coal and nuclear plants isn't a trivial matter, particularily nuclear plants. Neither of these types of plants can be started in a couple of hours. With coal plants you are looking at around a full day if the unit is cold. Nuclear is 2-3 times that. Startup costs are also very high, which is why these units are most economical when operating 24/7 at their rated capacity. There is also a cost with running coal and nuclear plants at less than rated capacity. The cost per unit energy increases. I think things could be done to have a very high penetration of wind on the grid (gas turbines, FACTS devices, more transmission) but there is a price. If people were willing to pay more than double for electricity the technical issues could be worked out...but very few people would be willing to accept this in my opinion.Doublee 03:12, 6 August 2007 (UTC)

Does mixing land based and offshore sites provide useful diversity to combat these intermittency effects?

Is there a potential need to build more natural gas turbines to deal with the intermittency?

And do control systems that shut off air conditioners for a half hour during unexpected drops in wind power have the potential to help? (Can such systems be designed to guarentee that enough power will be available to run the air conditioner at the user-desired duty cycle, and keeping the temperature within a few degrees of what the user desires, but cycling on and off in sync with when power is available from the grid?) JNW2 18:31, 4 August 2007 (UTC)

Investing in wind

Are there ways individuals can invest directly in for-profit companies that build wind farms? Is the capital available to such companies a limiting factor in how quickly wind farms are built? JNW2 18:31, 4 August 2007 (UTC)

Capital costs are the major problem with wind power; all the cash has to be invested up front. Thereafter, wind power is essentially free; unlike, say, Coal, which continues to require fuel costs over its lifetime. However you are unlikely to spur much more building, unless you are content with a lower rate on your return than the regular investment sources. The simplest answer may be to build a turbine yourself with some neighbours. If you just want to profit, you can buy shares in a wind company. - Mike —Preceding unsigned comment added by 83.147.143.193 (talk) 16:59, 5 January 2008 (UTC)

Electric Heat

If we get enough wind power someday, will it make sense to convert residential heating to electricity? If the hotest days have low wind speeds, it seems likely that the cold of winter will be a time when wind turbines are likely to produce plenty of power... JNW2 18:31, 4 August 2007 (UTC)

Not such an easy question to answer. First, electric heat has traditionally beeen the most expensive of electric, oil, coal and gas - that would have to change, or the resistance just flat could not be willingly overcome (people in the U.S. won't even vote small tax increases to support schools that are falling apart). Second, changing a house from one heating source to another is expensive - who is going to pay up front for that?

Myself, I'm all for it! Declare Global Warming to be a National Emergency in the U.S. and by fiat put in place a national building code. Stomach the screams of the small businessmen who make their money off of fossil fuel heat (which may well cost the next election). All we need is another Teddy Roosevelt in the White House.

But, in today's political reality, it isn't going to happen. Too many politicians like holding onto their jobs and the power those jobs bring. Simesa 01:34, 11 August 2007 (UTC)

Part of the reason that electric heat is most expensive relates to physics of the existing power plants. Most power plants in the US work by creating heat, and then converting the heat to electricity. There is some theoretical limit (66%, maybe?) to the efficiency of a heat to electricity conversion. If what you ultimately need is heat, it's more efficient to burn the fossil fuels near where you need the heat, rather than absorbing that conversion penalty. If wind power makes it possible to bypass that penalty, the cost of the electricity for heat may be more affordable, especially if it turns out you can rely on off-peak electric rates when you're paying for heat.

I believe that for at least a decade or two after WWII, coal heat in homes was fairly common; I'm not aware of anyone heating their home with coal these days, so it seems that people have historically managed to pay for conversions.

I've also been told that commercial office buildings often have multiple boilers, and it's not uncommon to see a mix of natural gas and heating oil among the different boilers in a building. These buildings would be even better places to put in electric heat than residences, because it ought to be practical for the grid to tell the electric boilers to simply stop running (and let the oil/gas boilers take over) if there's a sudden drop in available wind power. JNW2 15:00, 23 September 2007 (UTC)

"Declare Global Warming to be a National Emergency in the U.S. and by fiat put in place a national building code." Energy uses change, and have changed, over hundreds of years. Coal burning is no longer permitted in many urban areas because of the health problems they cause. The usual way of changing building codes (a regular practice) is to require new construction in new buildings; not to convert all old buildings, although subsidies can be given for conversion. think that a previous poster who mentioned taking air conditioners offline at low wind times had the solution. If we had a grid which continuously priced electricity according to availability, and if we had equipment controllers which could read the price in real time and switch on and off in response, we would have solved most problems. This isnt pie-in-the-sky either - its called an efficient marketplace. There is plenty of room for a lot of equipment to power on and off; we just never bothered as timer switches are simpler. But tweaking that to power availability instead will allow a huge amount of locally intermittent power onto the grid. Think recharging your electric car; storage heating, storage cooling, and so on; and then imagine a world where every house has a bank of batteries to accommodate electricity availability pricing. The reason man is the dominant species is because of our ability to adapt and utilize new sources. - Mike

Wind Power in Europe

Ref is: http://www.ewea-report2006 EWEA 2006 Annual report, Powering change, European Wind Energy Association or . The list I added is useful as it shows the development at glance. I was not allowed to add the ref in the article, is this correct? Watti Renew 11:39, 1 September 2007 (UTC)

Significant figures

74,223 MW? 73,904 MW? In 2006? What day/month? Since new turbines are commissioned perhaps hourly, it's a bit unproductive to twiddle a 5-signifcant-figure entry - "about 74,000 MW" or "more than 74 GW" is quite sufficient for any reasonable purpose. --Wtshymanski 18:00, 5 September 2007 (UTC)

Contradictory

From the opening section of the article: "[Wind power] accounts for approximately 20% of electricity use in Denmark, 9% in Spain, and 7% in Germany... The intermittency of wind seldom creates problems when using wind power at low to moderate penetration levels (though such intermittency has caused problems for grid stability in Denmark and Germany, where penetration is greatest).[3]"

According to the first statement, the order of proportion of electricity generated from wind power runs 1. Denmark, 2. Spain, 3. Germany. The second paragraph states that penetration of wind power is greatest in Denmark and Spain. I assume the two were written by different authors, or they wouldn't contradict each other. WikiReaderer 21:01, 8 September 2007 (UTC)

Impact on Wildlife

In the 'Impact on Wildlife' section, a statement is made about a wind farm in Norway killing a colony of sea eagles. The citation link for this is broken, and the failed verification tag was added last month. Upon searching, I couldn't find an archive of the original article, though I did find this BBC Article. I don't think this is worthy of replacing the citation, as it is a news article referring to the same broken link which, from what I can gather, was mostly anecdotal and unproven anyways. Being relatively new to editing, I'm just wondering what action I should take in this instance, if any. Thanks :-D Digitiki 20:30, 17 September 2007 (UTC)

POV

This article reeks of pro wind power POV. I'm not going to try to do anything about it, because I admit that I'd be unable to write in an NPOV style about this massive white elephant, but comments such as

1. Newer wind farms have more widely spaced turbines due to the greater power of the individual wind turbines, and to look less cluttered.
2. The aesthetics of onshore and near-shore wind turbines have been compared favorably to those of pylons from conventional power stations.

are simply leaping to the defence of wind power, with rather POV reasons. For example, "Look less cluttered" means to me the ugly things are spread out over an even greater area, and the pylon argument is complete nonsense - for one thing, pylons generally don't have as great a visual impact, not being painted white, stuck on or near skylines, and grouped together (as well as not having such a solid-looking construction), and who ever claimed that they weren't ugly eyesores either? This is especially an issue in England, where they tend to get sited in the few areas not already dominated by man-made construction and still retain their beauty. Putting wind turbines on places like that is like using the Mona Lisa to wipe your arse. I can only assume anyone who doesn't have a problem with the former wouldn't with the latter (or if they did, it would only be monetary).

When arguments against the things are raised, they tend to get glossed over rather quickly. - Riedquat 11:38, 23 September 2007 (UTC)

I would also like to comment on the POV in this article. The section "Economics and feasibility" has a list where the first bullet talks about the subsidies fossil fuel and nuclear generation receive and then in the second bullet talks exclusively about nuclear power providing very incomplete information. To me this seems like the previous editors are trying to justify wind power rather than provide information on it, especially since the second bullet doesn't even mention the word 'wind'. Also in the section "Scalability" there is the sentence "...this does not mean wind energy cannot be a significant source of clean electrical production on a scale comparable to or greater than other technologies, such as hydropower." This again seems like editors are trying to sell wind power rather than providing information. Right now I don't think this article is neutral. Nailedtooth 04:47, 4 October 2007 (UTC)

i concur, i agree there is a WP:NPOV problem with parts of this page, i have been working on cleaning up references, some of which, so far, have proved to be various grades of linkspam; however, this is a volatile subject, a controversial one for many people and a very active page with a lot of editing going on -- multiple edits every day since late September 2007. So everybody can help by pitching in to clean up, wikify etc. -- there's lots of stuff to do. David Woodward (talk) 17:00, 17 November 2007 (UTC)

Cost and Stats

I would like to do some research about purchasing a reasonably large windmill.
It would serve two purposes. 1) Electricity 2) it must be aestetically pleasing.
I would like to see the models to choose from ( this is for a public area not a house ) and some estimates of the electricy / savings it would produce.
I searched the net but I am not sure where one goes to purchase a windmill. --207.45.240.31 14:08, 26 September 2007 (UTC)

Recent edits require massive cleanup

The article has grown by 10 Kbytes in just the past few days. Much of the material is not directly related to Wind Power and either needs to be moved to sub-articles, or removed completely. Other sentences obviously violate one or more of the following: WP:NOR, WP:NPOV, and WP:VERIFY. Unfortunately I can't spend the time required to clean it up - I hope someone else can. —Mrand ^T-C 02:26, 28 October 2007 (UTC)

Thanks to Bobo159 for starting to trim this article back down! My impression is that the bulleted list in Grid energy storage section really belong in the main article on Grid energy storage, not here in an article about wind power. Any disagreements?—Mrand ^T-C 21:06, 31 October 2007 (UTC)

i second that, i've been editing refs in this section, but this stuff should be moved out, all but the intro para, to the linked existing article since there is one. David Woodward (talk) 16:26, 17 November 2007 (UTC)

I found the time to do just that. The article is still lacks focus and is burdened with too much detail, but if we all keep slowly chipping away... —Mrand ^T-C 20:11, 17 November 2007 (UTC)

Transpared

I have read somewhere about transparent blades. So, solar panels could be installed in wind farms (they don´t produce shades)--Mac 11:31, 30 October 2007 (UTC)

Dear Mac, i guess everybody is pretty busy around here, a lot of Wikipedians do this stuff in their spare time. If you get a chance, do a web search and see if you can get a reference for us, like a web page address or book or magazine details; that way somebody is much more likely to put this stuff in the article, because is it quicker and easier to do. Or you are encouraged to edit yourself, especially with a good reference. David Woodward (talk) 17:09, 17 November 2007 (UTC)

Long Island Offshore Wind Park Project

Here is another U.S. offshore wind project, that does not seem to be mentioned in the Wind Power article, nor have its own WP article like the Cape Wind (Massachusetts) project. A link to a federal government website with info is http://www.mms.gov/offshore/RenewableEnergy/Projects.htm I think it is worth a mention, or an article. Enjoy, N2e 22:37, 1 November 2007 (UTC)

Some comments from an outsider

The page looks good. Have you guys thought about GA status? I'm going through it and doing some copy editing. I've found some potential content errors and have some other suggestions.

• I think there is something wrong with this sentence: "There is an estimated 50 to 100 times more wind energy than plant biomass energy available on Earth."

I think there's a problem with the source's biomass number. On the solar energy page I put some energy comparisons in but I came up with a biomass resource of 1.8 ZJ/year using Smil and I cross checked this with data on the biomass page. The numbers agreed with each other if you assume an energy density of about 12 MJ/kg for biomass. I thought that was a reasonable assumption but then I ran into the 50-100 comparison above.

I also calculated the number using your source and came out with a reasonably close number to the one included in the note but it would be good if the note included its assumption for biomass energy density (MJ/Kg or BTU/lb). I can't blame you for this because I need to double back and put this assumption into the solar energy page calculation.

I looked at the wind reference provided for the 72 TW note. Seems like a good source and the note in the math works out. On the solar energy page I used a DOE reference to come up with 6 ZJ per year. Sort of a problem there but I think the DOE number might include offshore winds. Eventually, I would like the number on the solar page to reflect the total theoretical wind energy in the atmosphere. This is much different than the technically feasible number that should be used on this page.

I understand what the word "shape" means but it needs some more explanation or a link to where I can read about shape. The Mitchell 2006 reference at the end of the shape sentence probably explained it but this reference is quick formated and there is no proper Mitchell reference.

I only made it down to the Onshore section. I started making some edits where I thought edits were needed. I don't want to step on any toes here. Please comment on the edits I made and if they are appreciated I'll come back and go through the rest of the page. Be honest, it won't hurt my feelings. I'm not here to stay... just to help out for a bit if I can. Good luck all. Mrshaba 21:34, 6 November 2007 (UTC)

This is a rather striking picture from the german wind power page: [6]Mrshaba 17:31, 9 November 2007 (UTC)

Construction images

Are insufficient on this page.

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• 
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• 
• 

I will add some of these later. -Theanphibian ^{(talk • contribs)} 08:31, 16 November 2007 (UTC)

Renaming this article or separating it into two articles

I was wondering about the relevance of the information contained within this article. I feel that most of the information in this article belongs to the subject of Wind power (electricity generation) or Wind energy (electricity generation). I feel that the main article on Wind power/energy should possibly be restricted to the simple notion of its conversion into other forms of energy but no discussion on its use an alternative energy source. I hope I'm making sense here? Ga2re2t (talk) 13:36, 21 November 2007 (UTC)

Per WP:NAME "Generally, article naming should prefer what the majority of English speakers would most easily recognize, with a reasonable minimum of ambiguity, while at the same time making linking to those articles easy and second nature." Most people today think of wind power in terms of its use an alternative energy source, so the current name is appropriate.--agr (talk) 14:59, 21 November 2007 (UTC)

Deleting important information

Why was the information I placed on the site deleted - and then the article locked??

The 'Renewable Energy in Scotland Inquiry', compiled by the Scottish Parliament, was one of the most detailed and important studies into wind power. Yet every time I put so much as a snippet of this report on the site, it is deleted. Tell me - is this for eco-political reasons?

The Scottish report concluded that:

When a wind power station is connected to the grid a similar conventional capacity must be maintained as spinning reserve to cover the uncontrolled intermittency. The presence of an increasing number of distributed intermittent and unreliable micro-generators to replace more secure forms of generation leads to grid instability.

Wind energy will always be a secondary, intermittent, unreliable energy source and can never satisfy a base load demand. (Wind energy) is a profligate waste of our most precious resource - wild land.

This is a good honest report into the benefits and pitfalls of of wind power, and if this report does not deserve to be on this Wikki page then nothing does.

In addition, my section on grid storage was also deleted. As it stands, the information given makes it look to readers as though there are storage mediums available that could store enough energy to cover for a few windless days. This is utter nonsense, and so this Wikki page is giving a dangerously biased view of wind power. Is this Wikki's directive - to give out biased information to conform to some eco-political viewpoint? This page needs to add something like the following, in order to balance the information given.

Quote:

The problem that all grid energy storage systems face, is that wind-power generation system can go off-line for prolonged periods. For example, meteorological reports for Newport Rhode Island, a typical coastal site favoured for wind generation, show that in the month of September 2006 the wind rarely got above 4 kts (5 mph), whereas a typical wind generator requires at least 15 kts (8m/s or 18 mph) to start generating significant amounts of power. This means that significant amounts of energy need to be stored to cover these outages, which none of the methods cited above can fulfil. At present, pumped water storage systems have the greatest energy capacity, and the Dinorwig is the largest example of this technology in the UK; but about 140 Dinorwig-sized plants would be required to fulfull Britain's energy requirements for just two days. See grid energy storage systems for further details.

End quote. —Preceding unsigned comment added by Narwhal-tooth (talk • contribs) 10:54, 21 November 2007

Narwhal-tooth, you should really sign your name directly on the talk page with four tildes. It makes conversation much easier.

I also found the deletion of your information a bit over the top. See User_talk:Mrand#NOR_in_Wind_power_article for my comments on the subject. However, it seems that the problem is not necessarily with what you wrote, but rather the placing of your passage in the overall structure of the Wind power article. There is, for example, already a section on Wind variability and turbine power. Grid energy storage already has a main article of its own. The article is, it seems, too long and possibly needs restructuring. A section entitled Criticism of wind power showed probably be created for information such as yours. Also, it appears to me that there is some ambiguity between the notion of wind power in its own right (for windmills, ship sails, electricity production) and wind power in the modern sense as a green alternative to fossil fuel/nuclear electricity production. Ga2re2t (talk) 13:11, 21 November 2007 (UTC)

Noted, Ga2re2t, I did not know how the 'signing' was done. But this editing by Mrand appears to be the imposition of a Wikki eco-policy. Mrand has reduced my item on the Energy in Scotland Inquiry (four times now) to: "the Energy in Scotland Inquiry noted the intermittent nature of wind power"

No they did not - they condemned the entire industry - they said that wind power was 'a waste of space'. The last edit to my additions deleted the words 'and concluded that it was a waste of space'. (Which is what the report says.) Was this extra half-a-sentence so long that it needed deleting?[7]

Likewise, he has reduced the summary on 'grid storage' to only items which suggest that grid storage is a viable system for storing energy to cover for windless days, which it just cannot do. Again the summary on this page is far from balanced. Either Wikki is neutral, in which case it presents both sides of the argument, or it has a political agenda. Which is it?Narwhal-tooth (talk) 20:05, 21 November 2007 (UTC)

The page you quote from [8] appears to be one individual's statement (out of ~150 such statements) submitted to the committee. That would not be an acceptable source for Wikipedia. See WP:RS. The actual Energy in Scotland Inquiry report [9] expresses concern about some aspects of wind power (e.g. "We have grave doubts about the overall economic rationale for large-scale wind turbine installations in locations remote from the consumer") but these are based on specific conditions in Scotland (such as difficulty of connecting to the grid) and the report does suggest wind power has a role to play. See page 15. --agr (talk) 23:06, 21 November 2007 (UTC)

Narwhal-tooth, Wikipedia is neither neutral or biased. On the other hand, contributions from individual Wikipedia users (including you) may be either neutral or biased to some extent. You, and the rest of the world, are free to edit Wikipedia as you wish to add information which you believe to be neutral. But others are also free to remove that information if they feel it is biased. This can go on for a long time, with no real progress being made. This is where the talk pages come in. Here we give our ideas in a productive manner to improve the main article and overcome differences of opinion. Any consensus reached is only temporary as it is based on input from currently active Wikipedians. A year or two later a different consensus may be reached by different users. The aim, of course, is to reach a consensus that will be accepted by users for many, many years, if not forever. The current consensus is that your contribution to the Wind power article is out of place. The reasons are many and are summarised as follows:

• You selected a sample of raw data (an individual's statement) from the Energy in Scotland Inquiry as a reference, whereas only the actual report should be considered as a reliable source.
• This report, while as you mentioned earlier is a good honest report into the benefits and pitfalls of of wind power, is specifically targeted for use in Scotland and not as a general report for the planet.
• Your grid energy storage contribution is in the wrong place. Intermittency is discussed several times in earlier parts of the main article. Your contribution should be made in context with those contributions and not as a standalone statement.
• The entire article possibly needs some restructuring and trimming down and as such the best way to help improve this article is not by adding extra information, but rather discussing on the talk page how we can all work together to create an article that is neutral and that is appreciated by the wider population, not just wind power enthusiasts and critics.

Ga2re2t (talk) 12:11, 22 November 2007 (UTC)

Thanks, Garrett, but I still do not see the nature of my contibution as being the problem here:

• You, and the rest of the world, are free to edit Wikipedia as you wish to add information which you believe to be neutral.

No I am not, someone had locked the page and accused me of 'vandalism'.

• You selected a sample of raw data (an individual's statement) from the Energy in Scotland Inquiry as a reference, whereas only the actual report should be considered as a reliable source.

No, I selected the summary, which is what one does when there is not sufficient room to mention the entire report.

• This report, while as you mentioned earlier is a good honest report into the benefits and pitfalls of of wind power, is specifically targeted for use in Scotland and not as a general report for the planet.

And Scotland is where the UK government wants to place most of its wind power farms, for it is the best location - in terms of wind and open space - for such farms. However, as the Scots have pointed out, wind is not a good source of electrical power and it is a waste of Scottish moorland. That makes this report highly relevant to this web-page.

• Your grid energy storage contribution is in the wrong place. Intermittency is discussed several times in earlier parts of the main article. Your contribution should be made in context with those contributions and not as a standalone statement.

There always was a small summary on grid energy storage in this location. The only problem is it is highly biased, and unless people go to the main topic they will never find this out. All I added was ine paragraph of five or so lines, to even up this summary.

Narwhal-tooth (talk) 23:05, 24 November 2007 (UTC)

I'm trying to clean up the article some and make sure concerns are presented in a balanced way.--agr (talk) 18:59, 26 November 2007 (UTC)

--- "and it is a waste of Scottish moorland. That makes this report highly relevant to this web-page." You have repeated this a few times now, and every time I am puzzled as to what other, more valuable uses there are of Scottish moorland, which are prevented by the installation of Turbines. Turbines dont take up much space on the ground, so the amount of subsistence grazing lost is negligible. Last I heard, people were fed up of sitka spruce plantations (and even they might co-exist with tall enough turbines). So what precisely constitutes this "waste of space" and why havent these moorlands been used for this pressing purpose heretofore? - MIke p.s. the solution to the intermittency is to wall off a few glens and use them as part of pumped storage hydropower schemes. Sure, you lose some more valuable marginal land, but think of the ecological benefits in preventing the extinction of scottish wildlife through climate change. Ecological arguments aside, it can be done, and will result in a steady supply of electricity from wind farms. —Preceding unsigned comment added by 83.147.143.193 (talk) 16:34, 5 January 2008 (UTC)

Total percentage of world capacity

In 2004, the IEA estimated that wind produced 0.06% of the world's total energy. Now it's more than 1%? — Omegatron 05:52, 8 December 2007 (UTC)

I think you are comparing to world's total energy, not total electricity produced. The IEA does not seem to separate geothermal/wind/solar/other, but states that they combine to produce 2% of the worlds electricity. 199.125.109.134 (talk) 17:12, 18 December 2007 (UTC)

Yes, they separate it. They list wind power alone as 0.06% in 2004. http://www.iea.org/textbase/papers/2006/renewable_factsheet.pdf#page=4 The "electricity vs energy" difference is probably the cause of the discrepancy. — Omegatron 21:06, 30 December 2007 (UTC)

For 2005 with EIA data, and using the chart in the article, I get:

• wind: 171 TWh
• total world usage: 17351 TWh
• fraction: 0.00983006

It's 1%. -Theanphibian ^{(talk • contribs)} 21:52, 18 December 2007 (UTC)

Efficiency

{{editprotected}} In the section "Potential turbine power", replace the first image, "A Darrieus wind turbine." with Image:Wind power coeff.jpg with the caption "Wind turbine power coefficient." 199.125.109.134 (talk) 15:41, 18 December 2007 (UTC)

I see there is no effective equivalent in the article right now, so I added it. -Theanphibian ^{(talk • contribs)} 21:55, 18 December 2007 (UTC)

Disable editprotected template since edit was performed.—Mrand ^T-C 23:45, 18 December 2007 (UTC)

Safety

The section on "safety" has gotten out of control and is internally inconsistent. The hydroelectric statistic is 2000 times higher than the fatalities per terawatt-year provided by wind turbines, yet the section entirely over-emphasizes fatalities. I propose to rebalance this section. --Wtshymanski (talk) 15:22, 31 December 2007 (UTC)

See [10] for a list of fatalities per TW-year for a variety of power sources. It seems that the number for hydro quoted in the article is verifiable. And if 0.23 fatalities per TW-hour applies for wind, that would translate to 2014 fatalities per TW-year. So it makes sense to me, though more conversions in the article could improve it. -Theanphibian ^{(talk • contribs)} 15:37, 31 December 2007 (UTC)

The article is still quite prolix and I think could be under 64K with a little more care and attention. I've trimmed some of the low hanging fruit in terms of redundant sections, etc. - but we're a long way from brilliant prose. This article needs more deletions than additions right now. --Wtshymanski (talk) 19:08, 31 December 2007 (UTC)

If the safety section occurs as too long for you, then make a summary and break the rest into another article. All major energy sources need significant coverage on here of the big issues of which safety is a big one. -Theanphibian ^{(talk • contribs)} 21:43, 31 December 2007 (UTC)

The offered reference is sponsored by the nuclear industry and is not directly about energy production fatalities. At 2000 fatals per terawatt-year, we'd be hearing about *hundreds* of wind-related fatalities per year at the current US and Canadian production levels - now, I don't get the paper every day, but surely I'd have heard of some of these. Given the rapid growth of generation capacity, I don't think 1994 statistics are representative of current reality. --Wtshymanski (talk) 02:43, 6 January 2008 (UTC)

Gipe's web site [11]now (Jan. 9,2008) gives 0.15 deaths poer terawatt-hour as of end 2000, and is very interesting reading. Yes, a member of the general public was killed by a wind turbine - a parachutist who jumped onto one. Gipe's web site doesn't give statistics for the number of parachutists killed by regular power lines per year. The Web site also points out the statistics are skewed by the large number of tiny turbines at Altamont Pass and similar '70s-ear installations. Teh database claims 32 accidents total, inlcuding one crop duster who hit a met tower, the parachutist, and one apparent suicide. At 11,600 MW, 33% capacity factor, I'd expect 33.5 terawatthours per year generation in the US and at .15/twh , 5 deaths/year - doesn't seem to be the trend. Gipes says Germany is arond 0.07 fatalties per TWH I think the present0 section greatly overstates the risks to people from wind power O&M, and to the general public. --Wtshymanski (talk) 06:15, 9 January 2008 (UTC)

---

Moved from my talk — Omegatron 03:39, 17 January 2008 (UTC)

Have you looked at Gipe's web site [12] recently? He's further revised the fatalities per TWH, and the death statistics table includes one parachutist, a drowning , and an apparent suicide. --Wtshymanski (talk) 06:20, 9 January 2008 (UTC)

What do you mean by "recently"? I just edited that article a few days ago, and was looking at his site as I wrote it. The Caithness data is more comprehensive, and includes his. — Omegatron 00:23, 10 January 2008 (UTC)

Oh I see (from your edits). I interpreted that statement as "towards the end of 2000, the death rate dropped to 0.15 deaths per TWh", as in "the death rate for 1999-2000 was 0.15", but you're right: According to his database, there were 20 deaths from 1975-2000, and 130 TWh generated from 1975-2000, which equals 0.15.

He lists 12 more in the next 6 years, though, which are not included in this calculation (can we find total output generated during this period?), and the CWIF data includes 45 total fatalities for 1975-2007. The real numbers are likely significantly higher: Gipe says his data was incomplete and CWIF says that their data "is by no means comprehensive".

I wasn't including cases like suicides or distracted drivers in my tally, so as to avoid relying on "armageddonist factoids", as they say. I suppose I should be more sensationalistic when editing Wikipedia so that when partisans edit my work, it comes out neutral. ;-) I only considered the ones that are directly attributable to the construction or operation of the turbines. Killing oneself because of a debate about wind power is certainly a consequence of its use, but not a direct consequence of normal operation. (Also, what drowning?)

So we say "at least" and let the reader research the other cases for themselves. — Omegatron 03:39, 17 January 2008 (UTC)

For a ballpark calculation.... The total wind power capacity (which is not the amount actually generated) for 2001-2006 [13] [14] is 275 TW-yr?

But no... that's huge compared to 130 TWh. My calculation from EPI data is 81 TW-yr for 1980-2000, which is 5000 times more than Gipe's 130 TWh for 1975-2000. So total world capacity is that much higher than the amount actually generated? What am I doing wrong here?

I guess total capacity is the peak total power that could be generated at the end of the year if all the wind turbines on earth were at maximum rotation? So it's not really useful for this calculation? — Omegatron 04:44, 17 January 2008 (UTC)

I can't find any numbers by year. More searching later. Just found this though: "Wind power in 2004 provided an average of just 221 MW of generation (DUKES 2005)." Total "capacity" for 2004 was 48 TW, according to the above. — Omegatron 04:59, 17 January 2008 (UTC)

And yes, I picked the hydro number for comparison because I didn't trust the other numbers on that page (nuclear seems too low, and coal seems way too low, considering the amount killed by pollution). One source said it would be 10 times as high for coal if they included accidents that killed 1-4 people. It's hard to find reliable numbers for this subject. — Omegatron 05:02, 17 January 2008 (UTC)

Looks like this section is attracting some biased editing. Why was the tally lowered? I count 40 that are definitely and directly attributable to construction, operation, or maintenance, not including 1 boy in a small tower, 2 unconfirmed, 3 driver distraction, 2 suicides, and 1 member of the public electrocuted in unusual circumstances, which equals CWIF's total of 49. How do you count?

Also, it is not "cumulative worldwide". The sources state that they aren't comprehensive, and don't have much data from countries like Denmark or the Netherlands, which are a big chunk of the world's installed capacity. The real numbers are most likely higher. — Omegatron 03:37, 2 February 2008 (UTC)

Scaring birds/bats away with sound

Does anyone have info on scaring birds/bats away with high pitched sound emitters mounted on the land-based wind power units ? The sounds emitted are above human hearing range, but are aversive to birds and bats. —Preceding unsigned comment added by 208.116.128.58 (talk) 16:05, 20 December 2007 (UTC)

Have you ever heard of a deer horn? Just drill holes in the blades. Work is being done to research ways of reducing collisions. Birds also collide with all tall towers and buildings. One report simply stated that changes have been made to reduce collisions. 19:42, 20 January 2008 (UTC) —Preceding unsigned comment added by 199.125.109.89 (talk)

Aircraft turbines have a false iris painted to scare away birds, this may also be applicable to wind turbines.--Theo Pardilla 14:06, 8 February 2008 (UTC) —Preceding unsigned comment added by Theo Pardilla (talk • contribs)

Cost trends

I'd like to get something in the article explaining that the nature of the wind power business has changed a lot since the 1970's. We no longer have hippies turning out clones of '20s-era farm pumps in backyard workshops (or at least, these are no longer the leading edge of the business); to compete in utility-scale turbine construction requires a major investment in large-scale fabrication facilities. Making towers alone is a huge business - a 100-metre tubular tower is a whole different order of construction than the 10-metre lattice towers at '70s-era sites. Foundations, transportation, financing - all big business now, not easy to break in with a small shop. Can anyone find a good discussion of this as a reference? This is precisely the reason turbine costs do not continue to drop - the availability of new firms willing to take the risk of investing in construction of turbines has flattened out. --Wtshymanski (talk) 19:20, 6 January 2008 (UTC)

I think a section on construction would be good, or maybe something covering that economic history. I don't have any background in this, but I think it would be fun to research. -Theanphibian ^{(talk • contribs)} 00:51, 18 January 2008 (UTC)

Still No History Section?

At one time, wind power was a very important part of agriculture, particularly in the Midwest.--Landroo (talk) 15:46, 12 January 2008 (UTC)

"The Midwest" - where do you mean? Wolverhampton? Hardly agricultural. Hereford? I can find no information. MikesPlant (talk) 22:59, 2 April 2008 (UTC)

A history section has since been added on 20th January. I have just added a main template to link it to History of wind power and tagged that with Subarticle.-Wikianon (talk) 16:37, 22 January 2008 (UTC)