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See http://www.windpower.org/da/ak... (2013), or https://en.wikipedia.org/wiki/... (28% 2011).

Now that is renewable. Of course the rest is made of coal power to fill the energy holes both in Denmark and in Sweden that is using hydro and nuclear only, and therefore can't supply peak energy on it own.

With the type of bike talked about in the article, you can rule out rain and sweat as a show stopper, and then you're only facing blood when you have serious accidents.

It's not a panacea, amongst other reasons due to some of the issues raised in the article, but all too many people seem to think it is impossible to ride a bike to and from work on a daily basis (I'm not saying you're one of them).

This is in stark contrast with what you see in large European cities like Copenhagen, where 35% of all workers and students use a bicycle for their commute. That's a city where the municipality alone has half a million people, and what most people would consider the urban area has another 700,000 inhabitants.

Is it a panacea? No. But I wouldn't mind seeing what'd happen in Copenhagen, if the eWAW and similar bicycles were legal to use and affordable in Denmark. I'm pretty sure we would see a lot more bike riders.

It obviously won't replace everything - goods still need to be transported, not everyone wants to ride a bike (even if they don't have to provide any power themselves) etc.

It's a relatively small area, and since the eWAW seems to be capable of about 60 km unassisted at 30 km/h with a small battery (I'm guessing 500 Wh), this would rival make a lot of car commutes once you take rush hour into consideration, and with commutes about 30 km or less, we're not looking at close to two million inhabitants.

With a 500 Wh battery, you'd need 1,000 MWh to charge the batteries needed for two million bikes. Let's call it 1200 MWh by including some inefficiencies in transmission and charging. And let's assume that on average they need to be charged in 4 hours.

That requires 300 MW in production capacity, or to put it into perspective, roughly the same energy as put out by 8,000 cars using 50 HP. 300 MW is less than 8% of the wind power capacity in Denmark as of 2011. And as someone pointed out, charging a 500 Wh battery can be done with a relatively small solar panel. And while it'd obviously increase the weight and cost, I wouldn't be surprised, if you could get most of the 250 W, that the motor peaks at, from panels installed on the bike itself.

Incidentally the cost of charging a 350 Wh battery is less than one Euro (DKK 4.22/kWh or roughly 57 cent/kWh) at the most expensive prices I can find. It's pretty difficult to find a cheaper way to travel 60 km.

Sadly these bikes aren't cheap. Not even close to cheap. They seem to cost in the neighbourhood of 5,000 to 10,000 Euros, which puts them fairly close to the cost of a small car, and thus makes them much less viable as a replacement for the car for commuting.

It's a shame, because it'd make for a serious decrease in local air and noise pollution.

Energy is extracted from the area that the blades cover. Twice as long blades means four times the area (pi * r ^ 2), which in turn means four times the energy. Of course, it's much more complicated than that, you can't just make double the blade length for twice the cost (must be stronger, etc.) but still.

Here's some info:

http://www.windpower.org/en/tour/wtrb/size.htm

http://en.wikipedia.org/wiki/Photovoltaic#Energy_payback_time_and_energy_returned_on_energy_invested

http://www.treehugger.com/files/2008/01/wind_turbine_lca.php
http://www.windpower.org/en/tour/env/enpaybk.htm

http://www.windpower.org/en/tour/env/enpaybk.htm
http://www.wind-works.org/articles/EnergyBalanceofWindTurbines.html
http://en.wikipedia.org/wiki/Wind_power
http://www.bwea.com/energy/myths.html

This article is about staying close to the ~59% theoretical maximum predicted by Betz' Law over a wide range of incoming wind speeds, not magically eclipsing it. Save your sarcasm until you really know what you're talking about.

http://www.windpower.org/en/tour/wres/betz.htm

>have much larger, slower moving blades

I question this. Not because I'm against windmills: I'm not, and not because I know: I don't. A very large windmill moves at a much lower RPM than a small one, but that does not necessarily mean that the blade tip speed on the big one is lower than on the small one. On aircraft, 28" long props on KR1's, and the monster 4 meter long prop on the Corsair, both have the tip moving at about the same speed.

For efficiency, you want to have your prop moving as slowly as possible, but for maximum power generation you want to interact with as much air as possible. These guys claim that most wind generators have the tips moving at about 64 m/s. So I'm saying [citation needed.]

$126M buys 126000KW, i.e., 126MW of installed wind power. At a power factor of 30% this produces 38MW of power.

A coal powered plant would produce 300000 Tons of CO2 a year to generate this power. Three years of operation would mean 1M tons of CO2 not released into the atmosphere.

For a gas-powered plant, it would be 6 years. For an oil powered plant, 4 years.

A 38MW plant is not really much power, and is a drop in the bucket. On the other hand the research benefits from this project are not easily quantifiable. So I'd go with the research on this one!

References:
http://www.seen.org/pages/db/method.shtml
http://www.windpower.org/en/tour/econ/index.htm

Not true, current wind power installations pay their energy costs in a few months to a year. This myth surfaces on slashdot every time wind power is discussed. Why?

You can learn the basics of wind power at http://www.windpower.org/ . Criticize it then, you don't look as stupid as you do now.

Hydrogen and stored electricity are both a pain in the ass to deal with, and both generated via coal-fired power plants.

1. Global warming is increasing the average kinetic energy circulating in the climate
2. Greater kinetic energy results in stronger winds
3. Wind turbine farms slow down winds by converting a percentage of their kinetic energy into electrical energy

some numbers :
http://www.windpower.org/en/tour/wres/index.htm
The sun radiates 174,423,000,000,000 kilowatt hours of energy to the earth per hour.
About 1 to 2 per cent of the energy coming from the sun is converted into wind energy. That is about 50 to 100 times more than the energy converted into biomass by all plants on earth.

http://www.windpower.org/en/core.htm

All renewable energy (except tidal and geothermal power), and even the energy in fossil fuels, ultimately comes from the sun. The sun radiates 174,423,000,000,000 kilowatt hours of energy to the earth per hour. In other words, the earth receives 1.74 x 10 ^17 watts of power.

That's 174 trillion kWh every hour.. or 4,186 trillion kWh per day.. or 1,528,929 trillion kWh per year..

2003 world energy consumption.. 417.605 quadrillion BTU per year..
Divide by conversion constant 3412 BTU/kWh .... yields 122 trillion kWh per year...

I.E.. In one hour the sun delivers, to the earth, more energy than mankind consumes in a YEAR.

P.S. Just in case your worried about solar conversion losses.
Our fossil fuel society is based on conversion losses stacked on top of other energy losses.
The overall conversion efficiency of oil in ground, into miles traveled by a typical auto is less than seven(7) percent.

Ok the claim on the national geographic channel was energy costs for manufacturing a turbine were met in 3 months.

this website gives quite a lot of information regarding Danish windfarms

http://www.windpower.org/en/core.htm

It's not easy to get figures from that site on costs on individual projects.

http://www.windpower.org/en/pictures/offshore.htm

  Nysted Offshore Wind Farm

The most recent large offshore farm is Nysted Offshore Wind Farm at Rødsand built in 2003. The wind farm is located app. 10 km south of the town of Nysted on Lolland and consists of 8 rows with 9 turbines each. The total power of the 72 wind turbines each of 2.3 MW thus reaches 165,5 MW. The annual electricity production of the wind farm is 600GWh, enough to supply 145,000 (Danish) households. The wind turbine towers are about 70 m tall, and the rotor blades 41 m long.

What do you propose Iran should use for energy since you agree that letting them have nuclear reactors isn't a good idea?

Cancer is a possible from doses delivered by xray machines this is why operators get behind lead shielding

http://en.wikipedia.org/wiki/Therac-25
very famous case of patients getting killed by short high level doses. Lower levels of radiation over longer time periods can also kill and cause cancers.

I don't doubt that its possible to operate a reactor safely and store the waste safely in some parts of the world. Other parts well lets say an alternative is required.

Do you think the united states should depend entirely on nuclear energy and for how long 100 years a 1000, 2000?

Problem is you can't use nuclear to solve the worlds energy crisis. best you can hope for is to become fortress usa and live as free as your government see's fit. Since your always going to be the target of terrorist attacks.

My countrys going the same way we already have home grown suicide bombers who were born and brought up here.

Maybe the answer is less people in the world. China's addressing this now, birth rates are declining in western nations... if we can't generate the energy needed for our current population maybe it's not sustainable.

Yes I think Iran wants nukes, it also wants a reliable affordable energy source. An alternative is needed and really its going to be the west to show its viable

Ok the claim on the national geographic channel was energy costs for manufacturing a turbine were met in 3 months.

this website gives quite a lot of information regarding Danish windfarms

http://www.windpower.org/en/core.htm

It's not easy to get figures from that site on costs on individual projects.

http://www.windpower.org/en/pictures/offshore.htm

  Nysted Offshore Wind Farm

The most recent large offshore farm is Nysted Offshore Wind Farm at Rødsand built in 2003. The wind farm is located app. 10 km south of the town of Nysted on Lolland and consists of 8 rows with 9 turbines each. The total power of the 72 wind turbines each of 2.3 MW thus reaches 165,5 MW. The annual electricity production of the wind farm is 600GWh, enough to supply 145,000 (Danish) households. The wind turbine towers are about 70 m tall, and the rotor blades 41 m long.

What do you propose Iran should use for energy since you agree that letting them have nuclear reactors isn't a good idea?

Cancer is a possible from doses delivered by xray machines this is why operators get behind lead shielding

http://en.wikipedia.org/wiki/Therac-25
very famous case of patients getting killed by short high level doses. Lower levels of radiation over longer time periods can also kill and cause cancers.

I don't doubt that its possible to operate a reactor safely and store the waste safely in some parts of the world. Other parts well lets say an alternative is required.

Do you think the united states should depend entirely on nuclear energy and for how long 100 years a 1000, 2000?

Problem is you can't use nuclear to solve the worlds energy crisis. best you can hope for is to become fortress usa and live as free as your government see's fit. Since your always going to be the target of terrorist attacks.

My countrys going the same way we already have home grown suicide bombers who were born and brought up here.

Maybe the answer is less people in the world. China's addressing this now, birth rates are declining in western nations... if we can't generate the energy needed for our current population maybe it's not sustainable.

Yes I think Iran wants nukes, it also wants a reliable affordable energy source. An alternative is needed and really its going to be the west to show its viable

There is a problem with nuclear reactors and that is radio active materials and governments that are prepared to use radioactive materials for weapons. radioactive materials can be used to poison and cause slow death from cancer in lowish doses. Fancy a dirty bomb in your city?

Nuclear reactors run on radioactive material. Nuclear reactors also generate radioactive material. Radioactive material used for the production of atomic and nuclear devices generally come from a special type of nuclear reactor, called a breeder reactor. Radioactive material can contaminate things, but it does not "cause slow death from cancer in lowish doses". If that were the case, everyone who ever received an X-ray would get cancer, as would people who fly a lot. People are exposed to "lowish doses" of radioactivity every day. A "dirty bomb" can be made with naturally occuring radioactive material. Want some fun? Get a good bit of iodine and cobalt, set it in a natural uranium outcropping for a year or so. Then, go get it and analyze them. Then, read up on the effects of the isotopes that were created.

nuclear is big boys toys, if you want to solve your countrys energy problems with nuclear than you have to accept the rest of the world wanting and doing the same. who here is comfortable about irans nuclear program. Do you trust them? you can't just allow certain countrys to develop nuclear energy and then try to deny this energy source to the rest of the world no matter how unstable you view them. Do you honestly think your nuclear nirvana isn't going to be viewed with hatred from the eyes of citizens of other nations who have been kept out the nuclear club.

Yes, nuclear power is "big boys toys" and just as a one would not give a child a loaded gun, one does not give and tries to prevent immature, aggressively violent regimes from acquiring dangerous technology. They may view our "nuclear nirvana" with hatred, but they already view us with hatred because we will not bend to their will and follow their religion.

If iran was developing huge arrays of stirling engines would the world be worried, I doubt it. Harnessing energy sources like wind tidal solar energy farming bio fuels. to create an energy solution safe for the whole world to have is what this planet needs. As for costs I think you might find its not as expensive as we are led to believe.

http://www.windpower.org/en/pictures/offshore.htm

Shows a number of wind farm projects. national geographoic ran a documentary a few weeks back and in it they stated the time to recover the energy put into making one of the danish offshore wind turbines was 3 months. If the first world cannot balance it's energy demands without needing nuclear power then it's not going to be possible for the rest of the world either. So if we want our civilisation to be viable long term we have to develop an energy policy and technology that is sustainable and can be shared with the rest of the world.

If "huge arrays of sterling engines" are a viable, safer, and cheaper means of energy production, why isn't Iran building them? And, why isn't Iran building massive wind and solar farms and tidal generation facilities? They could, they have the ability, the money, and would actually get help from everyone, including the U.S. Could it be that they specificly want nuclear power to get the material to build nuclear weapons?

Did that National Geographic show say how much power was generated by that wind farm and what percentage of the local power was generated by it? Or how long it took, or will take to recoup the costs of putting up that wind farm? How about the costs of maintenance for a large number of metal struc

There is a problem with nuclear reactors and that is radio active materials and governments that are prepared to use radioactive materials for weapons.

radioactive materials can be used to poison and cause slow death from cancer in lowish doses. Fancy a dirty bomb in your city?

nuclear is big boys toys, if you want to solve your countrys energy problems with nuclear than you have to accept the rest of the world wanting and doing the same.

who here is comfortable about irans nuclear program. Do you trust them?

you can't just allow certain countrys to develop nuclear energy and then try to deny this energy source to the rest of the world no matter how unstable you view them.

Do you honestly think your nuclear nirvana isn't going to be viewed with hatred from the eyes of citizens of other nations who have been kept out the nuclear club.

The imbalance of wealth is tearing this world apart as it is, as energy costs rise this is only going to deepen.

If iran was developing huge arrays of stirling engines would the world be worried, I doubt it.

Harnessing energy sources like wind tidal solar energy farming bio fuels. to create an energy solution safe for the whole world to have is what this planet needs.

As for costs I think you might find its not as expensive as we are led to believe.

http://www.windpower.org/en/pictures/offshore.htm

Shows a number of wind farm projects.

national geographoic ran a documentary a few weeks back and in it they stated the time to recover the energy put into making one of the danish offshore wind turbines was 3 months.

If the first world cannot balance it's energy demands without needing nuclear power then it's not going to be possible for the rest of the world either.

So if we want our civilisation to be viable long term we have to develop an energy policy and technology that is sustainable and can be shared with the rest of the world.

I don't know about how many we have, but you do them every once in a while when driving around in the country.

"The only known site with bird collision problems is located in the Altamont Pass in California. Even there, collisions are not common" -- http://www.windpower.org/en/tour/env/birds.htm

This link is the nicest derivation I have seen online of Betz's law regarding the maximum effiency (16/27 ~= 59%) of any non-compressible mass flow capture device. At least the article doesn't claim to exceed it (40%, I think). But as for high drag-devices getting a better effeciency than a variable-pitch propeller? That sounds pretty suspicious.

http://www.windpower.org/en/stat/betzpro.htm

On the other hand, if it can endure much higher winds than a prop installation, its OVERALL effeciency might be higher, because the energy in a mass flow is proportional to the cube of the wind-speed; so the 1% high wind speed tail of the distribution contributes a large portion of the total energy captured by the turbine. Of course, having a bit more REAL info would be helpful in determining if this is just slick FUD or something real. And when significant data is not mentioned, it does make one tend to think there is something to hide.

Windmills are not really "Man's best hope for energy".

For clean non-pulloting energy production, it has emerged a as working solution for deployment now, and with huge potential for increased deployment in the sea in the comming years.

Does that mean with should we should researching other clean ways of generating energy? Hell no, find some ways to create large scale cheap solar cells, wave energy that works, energy storage methods etc.. but until something better and cheap arrives wind energy is able to account for a significant part of electrical production.

When is there the most wind? Spring and fall. When are energy needs the highest? Summer and winter.

That depends on location, both for production and usage. The production data I have seen for windmill located in northern Europe show strong production in autum, winter and spring and lower production in summer. Because this behaviour is rather predicatable it can be factored in with energy from other sources, e.g. water power plants.

Besides this they are not very powerfull (large number needed to power a city), Besides this they are not very powerfull (large number needed to power a city), kill loads of migrating birds (strange/macabre but true), and the weather is not exactly something stable enough to build your energy grid on. Oh yeah: it can be cloudy and windless.

Well compared to solar cells as was subject of this story wind turbines are far more powerful. Do not even begin to discuss the difference in cost per KWh between these two.

About birds at most locations they actually coexist very well with windmills. Some bird do die from impacts with wind mill, but you forgot to mention the thousands of bird that also die every year from impact with highrise buildings and high voltage power cables. Does this make US flatten Manhattan? What about the million of birds and animals that die in traffic impacts every year. Do we stop driving or do we try find ways to alliviate the problem? Like fences and designated road stregthes with high likelyhood of animal crossings. With placements of wind turbines the impact on windlife should also be considered, but the problem is far less than you think. In Denmark there has been made studies about windlife and windmills. You can read some about it here:
http://www.windpower.org/en/tour/env/birds.htm

I see much more potential in wave-energy; which probably hasn't taken off yet because one practice experiment in Norway got 'blown off' after a violent storm wrecked it, and because it isn't in the public eye much.

Yes wave power sounds like a great technology. But if wave power was a software projejct on Sourceforge it would have the project status of embroyic.

Indeed we should do research in this field, but for many comming years it is no where close to be a useful energy source that can be installed and deployed mass scale. In comparasion it is more likely that solar cells will be major business years before wave energy will be useful.

But now you will mention that they have some wave power unit on an island in Scotland, and the one in Norway. And far as I know there is even one in Portugal. But it is no more than experimental deployment. The problem with wave power done this way is that it requires very special natural conditions not found many places. You need a tall rock side, with ocean waves slamming right into it. Concreate construction in this enviroment is not easy and not cheap and you have to design for the strongest winter waves. ...And dont even get me started about problems with dolphins and baby-whales getting stucked in the internal pipings of your wave power plant :-).

Alternative is to use some sort of floating carpet that moves up and down with the waves passing under it. Again these things are just reasearch areas nowhere close to mass deployment.

Anyway, with new deployment of wind turbines in

I have good news for you.... you're wrong!

the funny thing is, the reason your "fact" is little known is because it just isn't true. The "energy payback" of most well sited wind turbines is less than a year. So we disagree on that, but I have a source for my fact http://www.windpower.org/media(444,1033)/The_energ y_balance_of_modern_wind_turbines%2C_1997.pdf

care to trot yours out?

Seriously, where did you get your information from, and where do this insane myths come from? If what you said were true don't you think people wouldn't be making them?

Migrating birds tend to like strong winds, which often place them in the same geography as wind farms. As a reference, see this interesting article on the Altamont Pass wind farm and its effect on raptors.

Millions of birds die every year from smashing into high-rise buildings, cars etc. Have we stopped building high-rise buildings ore cars because of that? No. Wind Turbines will have no significant effect on bird populations.

Here is an article on the Altamont Pass Wind Resource Area. Some good quotes from the article:

Birds avoid colliding with wind turbines in most instances. Certain behaviors may increase birds' risk of collision.
Night migrating birds rarely collide with wind turbines, contrary to some beliefs.
Low bird mortality has been found at European wind power sites

You start by building a 50 to 100 foot tower on top of your home so that the turbine will be high enough to be in wind flow without blockage from nearby obstacles (i.e., trees and other houses).

Research all about windpower here http://www.windpower.org/en/core.htm as it seems to me to be the bible of wind power.

Then, integrate the power that the turbine generates into your homes power grid. This is a good resource: http://www.homepower.com/

An article that caught my eye in Popular Science pointed to these folks http://windausenergy.com/ who are making a vertical turbine, a technology which has been around for quite some time but they say that with recent break thrus in material it actually makes it practical to use.

(Oh, and before anyone pipes up with the "wind turbines aren't efficient" thing, I'd refer you to the Carnot Efficiency of a heat engine. The typical thermal efficiency of a steam plant is around 40%, the total efficiency of a typical wind turbine about 35%. They're comparable, especially when you consider you don't have to go digging for wind's fuel.)

I wonder what would happen to a wind turbine in a hurricane?

The turbine will turn itself off. It won't allow it's blades to go too fast.

Turbines have a cut in and cut out wind speed, which are wind speeds in which the turbine will turn on and off. The turbines I have studied will turn on at 3 m/s windspeed, and turn off at 25 m/s.

Of course, the wind speed also dictates how much energy will be created. A 3 m/s wind speed will generate a lot less energy than 12 m/s. Also, the energy creation is a bell curve, so wind speed higher than optimal will also have reduced energy output.

Energy output is not gauranteed to be what the turbine is specified for. The site's wind speed and temperature fluctuations throughout the year will be what actually determines the energy output. Also, one season could produce a lot of energy, while another season won't produce much energy at all.

You can use this calculator to play around with different turbines and different site attributes to see how much energy will be output. You can then use this website to find out the wind attributes of your area, so you can find out how much energy a turbine would produce if it were in your backyard. (New Yorkers and New Englanders have more detailed wind information available, right down to your GPS coordinate!)

I linked to a site that is provided by the danish windturbine industry. They give a nice description of how to optimize the design.

As regards taking energy out of the wind, the atmosphere's about 11km high, and the wind profile goes up from zero at ground level to pretty fast up in the jetstream. A turbine's wake is mostly dissipated at about 8 turbine diameters downwind, too. So even a wind turbine of this size might only affect less than 1% of the total atmosphere's height, for less than a kilometre horizontally.

"Someone feel like doing the physics to work out.."

"The guided tour is written for people who want to know a lot about wind energy, short of becoming wind engineers."

For anyone with a long list of questions they think will be best answered by posting them on slashdot, the windpower.org website has enough to keep you occupied for the rest of the evening.

Power output calculations here - remember it's statistical, so don't just assume constant wind speed and multiply it by the average weight of air

"Someone feel like doing the physics to work out.."

"The guided tour is written for people who want to know a lot about wind energy, short of becoming wind engineers."

For anyone with a long list of questions they think will be best answered by posting them on slashdot, the windpower.org website has enough to keep you occupied for the rest of the evening.

Power output calculations here - remember it's statistical, so don't just assume constant wind speed and multiply it by the average weight of air

v(z) = v0 ln(z/z0 )/ln(z1 /z0 )

Here v0, z0 and z1 are constants. Here is a nice site about windmill engineering.

v(z) = v0 ln(z/z0 )/ln(z1 /z0 )

Here v0, z0 and z1 are constants. Here is a nice site about windmill engineering.

"There's a big push from the nuclear lobby in the UK to build another power plant before renewables get entrenched and any story about reduced risk / improved waste handling will get media attention."

Unfortunately, it takes a lot of real estate to build renewable source on the scale of baseline output of nuclear powerplants (day/night, windy/calm 2300MW, availability 85%).

to give an example, Denmark is one of the leading countries in wind generators, with 3000 megawatts installed capacity.
According to the article, it is as much as 15% of the total demand. Imagine what a calm spell would work on their trade balance. And unfortunately, it takes all of 5500 wind turbines to reach that goal.

On the other hand, one single nuclear site can easily reach 1500 MW.

Lots.

The Danish Wind Industry Association says infrastructure is just under $100K per 100Kw peak production... our total peak capacity is about 1 TW. At 100% efficiency, that's $1 trillion (assuming I'm not doing slashdot math). So expect the real cost to be at least 4X that (guessing?)

Sorry to reply to my own comment, but this study by wind power advocates suggests an energy payback time of three to six months, a small fraction of a windmill's lifetime. Even assuming they're out by an order of magnitude, a turbine should last at least 20 years and so the energy produced is way larger than the energy used to produce the turbine.

"However, I often heard by experts that power from wind cannot be more than 20% or else the fluctuations become problematic."

So either:
(a) Install energy storage (warehouses full of fuel cells), the method being developed at the moment
(b) Install energy storage (pumped hydroelectric) is being used already at loads of places, and does wonders for the reliability of your grid.
(c) Do whatever the danish do... they have something like 90%+ wind-power and seem to manage

Do a search on "Dinorwig" for more info on pumped hydro, or the danish site for wind power.

Wind is nice and clean, but it takes a lot of windmills to generate enough power to replace a power plant. Windmill farms are regarded as many to be ugly so people don't want them around their houses.

Actually, the entire electricity requirements of the United States could be served by wind turbines with a combined land-use footprint of only 14,000 acres, including enough grid redundancy to provide 99.5% uptime through long grid transmission to areas experiencing calm winds. (The remaining 0.5% backup could be hydro or whatever.) That area is only twice the size of the Stanford campus, and as large as the amount of Oak forest that California loses each year.

Some people consider turbines ugly at first glance, but more people want wind turbines in their neighborhood than want mercury-spewing coal smokestacks in their state.

Wind power is the fastest growning renewable industry and is expected to be the dominant form of power production in less than 30 years.

Please see the Windpower FAQ for more information.

Tiny particles of soot or chemical compounds like sulphates reflect sunlight and they also promote the formation of bigger, longer lasting clouds.

This means, as has been often noted, the atmosphere is absorbing more energy. That in turn is great news for wind power, a renewable industry which is growing rapidly and in fact is expected to be the dominant form of power production in less than 30 years.

Only problem is, in the specs that used to be on the website, they exceeded the Betz Limit, the theoretical limit of wind turbine efficiency. There's no way they could reach the figures claimed.

It's interesting to note that they've taken the claims off their website over the weekend.

I still think the whole fusion reactor thing is a boondoggle. All we need for 100% of our electricity is wind (supplemented with a little hydropower and/or fossil gas to take up the slack during periods of calm.) Unlike fusion, with grandiose schemes of going to the moon for fuel, wind is actually in production and growing like crazy, crating thousands of jobs in addition to actual commercial power.

Ask me again about fusion and going to the moon in another hundred years.

The 2.5 megawatt turbines from Denmark do not kill birds, and they are essentially quiet.

You have to wonder about a politician who doesn't tell voters about his drunk driving conviction, because, he said, he didn't want to set a bad example for his children and then doesn't tell the Secret Service to keep them out of bars underage. Maybe he thought it went without saying. I guess you've got to be very precise when you've got pardoning powers.

Neither precision nor accuracy are Bush's strong suits.

What are the actuarial costs of promoting nuclear energy in the U.S. at a time when the U.S. is asking the international community to more closely monitor Iran's research and development in nuclear energy?

If it were not for the Prace-Anderson Act, nuclear operators would be required to obtain insurance on the open market. Please correct me if I am wrong, but this lack of subsidy would push the cost of nuclear electricity far over $0.22/kwh.

Quoting operating costs ignores all externalities, not just waste disposal and insurance.

we'd have to cover Arizona, New Mexico, and Texas to get as much as we need.

On the contrary, we would need only 14,000 acres of turbine footprint area, using modern turbines, for all of the U.S. current electricity demand.

Please read the FAQ.

http://www.awea.org/faq/land.html They say to provide 20% of America's electricity, you'd need 0.6% of the land of the entire lower 48 states! That's 16,000 square miles.

I don't know what is the problem with the AWEA. They don't return my calls, and I don't know why. I am beginning to suspect that they have been infiltrated with shills.

Please read the FAQ from Denmark, where the most efficient turbines are designed and built these days.

9. Wind Energy Uses Land Resources Sparingly

Wind turbines and access roads occupy less than one per cent of the area in a typical wind park. The remaining 99 per cent of the land can be used for farming or grazing, as usual.

Since wind turbines extract energy from the wind, there is less energy in the wind shade of a turbine (and more turbulence) than in front of it.

In a wind park, turbines generally have to be spaced between three and nine rotor diameters apart in order not to shade one another too much. (Five to seven rotor diameters is the most commonly used spacing).

If there is one particular prevailing wind direction , e.g. West, turbines may be spaced very closely in the direction at a right angle to that direction, (i.e. North-South).

Whereas a wind turbine uses 36 square metres, or 0.0036 hectares to produce between 1.2 and 1.8 million kilowatt hours per year, a typical biofuel plant would require 154 hectares of willow forest to produce 1.3 million kilowatt hours per year. Solar cells would require an area of 1.4 hectares to produce the same amount of electricity per year.

Trouble is, wind farms don't generate much electricity.

On the contrary, the entire United States of America can be converted to wind powered electricity using only 14,000 acres of turbine footprint area on existing farmland, pasture, and prarie. That's about twice the area of the Stanford University campus, or about as much oak forest lost in California each year.

The unsubsidized, fully amortized cost of wind power is about $0.04/kwh. Most jurisdictions provide a subsidy for wind. The more heavily subsidized typical cost for U.S. nuclear power is around $0.12/kwh. That doesn't include the cost of the blanket insurance policy courtesy of the Price-Anderson Act, nor the cost of waste disposal and other externalites like terrorism and natural disaster vulnerability, which can not be measured until it's too late.

More efficient omnidirectional prototypes were tested in the 1980's but they were banned because they tended to attract and kill birds.... There's also the liability problem of broken windmill parts falling on cattle (many windmills are on farms and ranches) or even people.

WTF? If it wasn't for your final paragraph, I would be sure you were a shill for the nuke industry. Your information is either very outdated or just plain wrong.

Please read the FAQs.

Denmark built an off-shore wind farm, which seems like a pretty good idea. The wind currents are stronger over the ocean, and it doesn't take up any land. Includes pictures.