Having done design work for Windlab Systems - a wind modelling company in Australia - we have often discussed this issue.

The short answer is that well situated wind farms and well placed turbines within those farms DO NOT cause a significant number of bird deaths (say any more than any high object like a building).

The problem lies with some older farms that have been placed within bird migration paths in mind. It's important to differentiate this as new wind farms should not be opposed if they are situated in the right locations - something Windlab Systems and others work very hard to make happen.

does anyone know about the newer larger windmills that are better for birds because they spin slower? please post info!

Charles - you hit the nail on the head!

To All...

There is a BIG difference between the number of bird causalities regarding larger turbines - and yes. Much of this has to do with the larger swept surface of the blades and much lower rotation speeds.

That being said, I really don't know where wind opponents get off with studies based on places such as Altamont Pass, which has been around since just after the enegy crisis of the 1970's. The turbines there are archaic in technology. Not only do those OLD turbines spin faster, but the hub heights are much lower to the ground, meaning that they do enter the flight paths of many birds that fly close to the ground. Newer turbines have hub height between 80 and 105 Meters - blades being 30 to 50 meters off the ground. Out of the flight paths for most of our avian friends. Also note that new wind farms go through much more stringent assessment processes that take things such as bird flight paths into account.

Ona personal note - I spent some time this past weekend at a location where there were three Vestas V80's and I can tell you that I didn't find any dead birds.. no seizuring cows and was able to have a pleasant conversation directly under one of the towers... and could hardly hear the blades churning over the blowing wind. But I did I hear somewhere that wind turbines are a leading cause of erectile dysfunction? It must be true!

Bottom line.. there are plenty of NIMBYS and other nay sayers that will say whatever they can... but really. I think wind is fairly inert in comparison to many of the alternatives.

I was walking through the inner city when a local native bird, a honeyeater, flew into a galvanised lamp post. It broke its neck but didn't die instantly. It lay sqawking for maybe 20 seconds while I tried to decide whether or not I should put it out of its misery. I was wondering whether the problem was of the shiny pole reflecting sunlight and confusing the bird. Just an idea.

I would think that maybe just coloring the blades of wind turbines other colors than the standard white would help out a lot. White blades on a fan are hard to see if say they were yellow or orange or red then I'd think they would be maybe more visible to the birds.

@thespyofcharles,

There is a wind turbine design that is not only more efficient, and quieter, but DOES NOT KILL BIRDS. I heard about it here on Treehugger, but for some reason, I've never seen it deployed.

The company that invented the turbine I'm talking about is Terra Moya Aqua. They have a very unconventional vertical wind turbine that will turn even at lower wind speeds, and best of all, it does not kill birds.

http://www.tmawind.com/

Putting a whistle on the tips of the turbine blades is not good enough; the problem is, the birds ride the air currents up the sides of the hills. That's what their instinct tells them to do. With or without whistles, they'll ride the path of least resistance, and WHAP! they get sliced by a turbine blade.

The solution is the vertical wind turbine by Terra Moya Aqua. It was developed a while ago, but for some idiotic reason, either they really suck at promoting themselves, or the wind farm owners don't want to spend the money to make the changes.

Unfortunately there a number of problems the Altamont Pass wind farms, which are not associated with the wind farms of today. It is important to understand these differences to avoid making generalizations about today's wind farms based on those at Altamont Pass.

My understanding is that there was no centralized plan for the wind farms in the Altamont Pass. This lead to a hodge-podge of poorly planned wind farms in the area. Numerous developers packed as many turbines as possible on their property without consideration for "dirty air" from turbines upwind. This resulted in significant inefficiency in power extraction from the wind, and also a high density of low, rapidly spinning blades in the area. Not surprisingly, the chances of bird strikes are greatly increased.

Wind farms currently being constructed use much larger towers than in the Altamont Pass, and they are arranged further apart. This greatly increases the efficiency of each unit as well as reduces the number of obstacles birds must avoid.

As a raptor expert I can tell you that the new wind turbines are no safer for the birds. The turbine blades only appear to be moving slowly while in actuality they are traveling at over two hundred mph at their tips. Additionally, the Altamont Pass newer turbines are killing more of certain species not less.

As to cat kills... cats don't kill eagles. Cats mostly kill songbirds.

But once eagles and other birds become endangered all causes of additional mortality can shift the death toll exponentially.

I find it hard to believe that enviromental groups are so supportive of wind energy. The government must take action on regulating the siting of industrial trubines.It is easy for others to be pro turbines when you don't live by them.Our property values are diminished.We see less wildlife.Noise and flickerling are major issues. Two adjacent land owners have recently taken a wind company to court because they were unable to sell their property.The judge ordered the company to pay the landowners fair market value of their property.There are real problems out there.But when the subsidies are gone so will the foreign investors.

The birds of prey are not "migrating" through the Altamont pass. And they do not fly low enough to hit the spinning turbines. They are not riding currents of wind into the turbines either. They actually fly well above them. But the terrain consists of endless grassy hills, so it is covered with mice, rabbits, snakes and other tasty morsels. The raptors hit the turbines when they dive for their prey. And it's more like hitting a truck than a blender.

I grew up by the Altamont pass. I remember when the first turbines were erected. And I watched it quickly grow to the largest wind farm in the world (at the time). And yes, the designs are old, small, crowded, and low to the ground, which is a poor design for efficiency and life around the turbines. Furthermore, the wildlife impact was known at the time. So, the problems there should not be associated with wind power in general. It was a new thing, and a lot of lessons have been learned from it. Now, it needs to change and apply those lessons learned. But no one wants to dip into profits...what's new?