PopSci reader aaronmrosen wonders: "when it comes to wind farms, can too many props actually slow down the wind, and cause a change in weather patterns?"
What do you think? Wind power: good or evil? Discuss in the comments section.
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I was musing on this topic myself recently.
I thought about mountains and building and skyscrapers. Do they stop the wind? No, they simply divert it momentarily. Windmills cause a much smaller disruption, as the wind impacts so much less surface.
If we pull our view back from the earth, it's easy to see that even if a huge percentage of the the earths land was covered with windmills, it would hardly be a noticable fraction of the entirety of the atmosphere.
Fear not, the pink lawn flamingos will continue to entertain us no matter how green our energy becomes.
after all, if wind wasn't affected by windmills, it'd be a perpetual motion machine ...
The question, perhaps, ought to be : what's the carrying capacity for the wind in my area? How many wind turbines will it handle before there's a noticeable effect?
A similar question could be asked about water flows and dams .... I'm sure someone out there has the fluid mechanics background to fully answer this ....
If mountain ranges and tall buildings dictate the locations of deserts and areas with a lot of rain, then why shouldn't windmills do the same?
It seems that everything man does or invents impacts the earth. That is part of the ecco system. If you look at the long term history of the earth the current ecco system is just a short act in the play. Should we do nothing? The earth is always changing. The spiecies that does nothing dies.
Even though wind turbines will change the wind flow and ecco system only time will till if it was worth it.
Any action has an equal and opposite reaction. Use your natural intuition. The energy that is harvested by a windmill is now taken away from the wind but it amounts to a handful of mosquitoes in a three acre swamp. In other words, it's a pinch removed from a heap.
A lightning bolt more or less hardly changes the overall impact of scattered thunderstorms even though just one bolt could run my house for a year if only I could bottle it!
I'm sure we could never put up enough windmills to replace the natural wind patterns we lost from forest clear cutting.
According to the law of conservation of energy, energy cannot be created or destroyed, so the energy gained from a windmill doesn't just appear, it has to be taken from the wind. I don't think the wind would be deflected by a windmill the way it's deflected by mountains or skyscrapers, the way Fatewilleatyou described it (and if it did then large "windfarms" could possibly create a rain shadows, which would change weather patterns), but would rather be forced through the multiple turbines, slowing the wind down. I don't know if I got everything right, please correct any mistakes, I would really like to hear more opinions on this.
Also, it's spelled "ecosystem".
The thing that people are missing is that wind turbines are actually not that tall. They would only affect the wind really low down. The real powerful wind that affects global and regional weather patterns is miles up.
Wind power would have to have an effect on the environment. You're taking energy out of a system for other uses. It has to make a difference, even if it'll take years to see it.
I think that figuring out how to make roof shingles that are solar would be a less invasive energy source. The sunlight falling on our houses and buildings is already being used for heat. Creating electricity with it would just make it portable. Our use wouldn't have that much effect 'cause it would just make heat where we use it.
You can lead a horticulture, but you can't make her think
So, Ihopki01, you're saying that there will be no impact on the weather if the wind at ground level is affected? I have to disagree, if you slow the ground level winds down there have to be some sort of repercussions, besides, mountains that cause rain shadows are not always several miles in height, and they tend to put wind turbines on higher ground, such as mesas, from what I've seen here in Texas.
Wind turbines aren't higher than 60m. A mountain range that causes a rain shadow is going to be much taller than that. Also mountain ranges that do cause rain shadows are just that. Ranges. They're massive. A wind farm has nowhere near the mass of a mountain range. It wouldn't redirect wind or create thermals or anything that would affect the weather. Having a wind farm on top of a mesa would have less effect than planting a few trees on top of a mesa. There is more energy in the wind at any given moment than humans will ever need.
Think big. What causes wind? A high pressure region is created from the heat of the sun, and the air escapes to a cool, low pressure region.
Mountains are large, solid bodies and can redirect the escaping high pressure air, creating new weather patterns.
Wind farms do not have the same ability. Sure they may slow down the moving air a bit, but no more than the boundry layer effect across a great plain. And this is only low altitude wind. The high altitude wind, the main player in our weather creation, wouldnt see any change.
So, does it remove energy from wind? Obviously. Is the energy lost replaceable? Yes, until the sun burns out, but then we'll have a bigger problem on our hands. Is this something anyone should worry about? Im not going to lose any sleep...
Besides that, whats our alternative? Keep burning fossil fuels? I think stealing a bit of wind has less of an impact than the billions of tons of co2 we dump...
purepower: The cleanest energy source we have is nuclear. It's unfortunate that politicians have been convinced that it's a deadly poison - if we were allowed to recycle our current nuclear waste, there wouldn't be any concern regarding long-term storage. What would actually be disposed of would be no more harmful than your average x-ray session at the dentist after 100 years or so while simultaneously decreasing the amount of fuel needed to generate power, eliminating the risk of refining the waste into weapons-grade material (it's just not possible at that point), and making the entire process much safer for everyone.
As to the question, I certainly believe that mass deployment of wind power would have a noticeable effect on localized weather. You're decreasing the wind speed at ground level thereby decreasing the wind chill factor and artificially raising ambient temperatures by several degrees. Wind power works great for localized demands, where the impact of transmission losses are minimal but is crummy for the US's vastly spread out infrastructure.
Purepower, lets stay on topic, let's not turn this into a discussion on whether man is the cause of global warming, that's not the point of this discussion.
To the topic at hand, the energy has to come from somewhere, there is no such thing as free energy. It may seem like wind farms are insignificant but hypothetically, if we were to build enough wind farms to provide the majority of the power needs for the world, you don't think that pulling that energy out of the atmosphere would have any affect?
I've read that the temperatures beneath the wind farms increase on average of 2 degrees F. Now what if that temperature increase was over hundreds of thousands of acres of land, such as would be required to provide a significant amount of power. I would think that might have an effect on wind patterns.
And wind farms are what 20% efficient? Maybe 50%? If we have to pull out 130 million kWh of power per year, out of the wind, to power a small town, you still don't think trying to power the whole country with wind would have a drastic effect on wind patterns?
And replanting all of the trees is not the same as building wind turbines. A forest creates a boundary layer, very similar to what happens in the study of fluid dynamics. It creates a very turbulent flow at the surface of the earth. But wind turbines are designed to take advantage of a laminar flow, maximizing the friction on the blades. This is why you build them on open plains, mesas, the flow is closer to laminar on an open plain, thus maximizing the air friction on the turbine blades. This pulls more energy out of the system.
We've been changing the wind patterns ever since we cut more trees than are grown in replacement, then there are the tall buildings.
Personally, given UK was once full of forest and by removing trees, we allow the north Atlantic winds to scream across the open fields until they hit someone's house ... the more wind turbines removing that energy may just reduce the frequency and size of storms and hurricanes.
I think its important to realize where we are taking our energy, no matter how small of a pinch we are taking.
So the question is: what does wind do? Among other things, it cools the earth through osmosis, and spreads pollen for plants.
When we convert Wind to Energy, we are borrowing energy from: cooling the earth and spreading pollen.
What about solar? Well if that light hit the earth it would warm the earth. So when we convert solar into energy, we are borrowing energy from Heating the earth.
Which of these options sounds like the best idea in light of our worlds controversy over climate change?
Tide power is taking energy from the gravitational pulls of the earth and moon. Geo Thermal takes the heat from the core of our planet and converts that into energy. Nuclear uses a natural resource and turns it into something potentially harmful if released; much like coal and oil.
Before investing heavily in any technology, we should consider the impacts we will be pinching off of these natural processes!
Even if wind and solar power does have an environmental impact, I would still think that it would have less of an environmental impact than fossil fuels. If you draw the energy out of the wind environment, the wind still blows, and theoretically it should still do what it needs to do. Same thing with the sun-it will still burn as bright as it does if we don't have solar panels.
However, with fossil fuels, the impact is immediate and obvious-you are drawing out petroleum from the environment, burning it, and releasing it as carbon dioxide.
So even if there's some sort of impact with wind power, we should still pursue it as a preferable alternative to fossil fuels.
How will creating a gigantic windfarm affect local and global climates? The answer is no one knows. It's obvious that no one on this thread can support their claims with any evidence. Someone deinfinitely needs to conduct a study about the effects of large scale wind farms on weather before we cover the midwest with turbine that might possibly, although unlikely, create desert.
Kyle.Brandenl, yes, all this is just speculation, but that's the whole point of this article, to compare and share ideas. I completely agree that this needs to be tested.
Also, I don't know about anyone else, but I'm not against wind power, I would just like to know what the side effects are before we start mass-converting wind power.
To lhopki01, I apologize, my second comment made it sound as though I thought that the wind turbines would deflect the wind, but I believe, as I said in my first comment, that it's more likely that the wind would be slowed down, not deflected. Also, concerning your comment about wind farms not being as massive as mountain ranges, you're right, but this whole thing started with an article that had an estimate that stated that wind power could make up as much as 20% of the nation's energy by the year 2030, and for that to be possible there are going to be massive increases in the amount of wind turbines. As they are, I agree, they aren't going to have a large affect on the weather.
That is a huge, complex model; not susceptible to off-the-cuff answers that are at all valid. We can only mildly predict weather and look at the huge farce that the bad models caused with Global Warming false alarms.
But like an earlier commenter said, we can't just sit quietly and do nothing.
Anytime something is done in extremes it will have extreme consequences.
Depending on the enviroment that the wind mills are introduced into, will obviosly have different consequences on the land and habitat that already call these places home.
If the land is desert that has had its land stripped of vegatation by wind, then the slowing calming effect of the wind mill on the wind, the less vegatation stripping effect the wind will have.
Pollination will also be affected along with errosion and possibly water evaporation. The variables are limitless, but no doubt there will be a change in areas that have too many wind mills installed.
In some locations these changes will benefit the existing habitat and other locations will have a negative impact.
All said everything we do must be done in moderation so not too over impact one area.
Hydroelectric dams are said to slow the Earth's rotation and disrupts aquatic life in streams, rivers, and oceans. Potentially, the same energy taken from the wind could also slow the Earth's rotation, as well as harm birds and bats. Solar energy steals light and heat from the environment...
Everything we do has some impact. Diverting energy from our ecoystem will have ramifications. The only question is how large the changes will be and whether we can harness the changes in a positive way.
FloDesign has a new design for wind turbines that looks like a jet engine, that reduces turbulence and allows turbines to run more efficiently, at higher wind speeds, and closer together. This can reduce the impact on birds and bats and make windmills more attractive.
Environmentalists are already noticing and measuring the impact of windmills on rain patterns, humidity, and turbulence. The answers are coming...
The wind she blows in the spring
The wind she blows in the fall
But in the summer when it's hot
The wind she doesn't blow at all
The birds fly north in the spring
The birds fly south in the fall
If they build all those damm windmills
The birds can't fly at all
What happens if global warming changes the wind patterns?
Lets say you have a 1,000 acre wind farm and you decide to replace it with 1,000 acres of trees, no one would even consider the question of how much the trees slowed down the wind. Everyone would think it's wonderful to plant all those trees. And that many trees would slow down the ground wind many, many time more than a wind farm. So why are we even concerned about the minor effect of a wind farm on wind at ground level when it's creating a clean source of energy - something we don't do much of in our so-called modern society. Disrupting rivers with damns, burning fossil fuels, figuring out what to do with radioactive waste materials, etc. are all far more damaging.
What if we put up a bunch od rather large fans past the wind mill to help increase the wind speed that we slowed down.
Hopefully by the time windmills would drasticly alter the the
weather patterns we would have left the earth to destroy
other world habitats.