The future expansion of wind power is limited by availability of battery and pumped storage. And they kill birds. Time to consider small, vertical wind turbines.

When I was a little boy is Sweden my father had a dear old friend that was so in love with birds and they with him that he had a great horned owl that came down and sat on his shoulder when he called. I was only three years old at that time, but the sight of this giant bird coming down from the big spruce tree is a sight I will never forget. Since then I have always enjoyed watching birds, normally soaring hawks, but on occasion eagles, rare as they may be.

Later in life I got gloriously saved and started reading the Bible, and one verse from the prophet Isaiah stands out :Isaiah 40:31 But they that wait upon the Lord shall renew their strength; they shall mount up with wings as eagles; they shall run, and not be weary; and they shall walk, and not faint.

I am now at the stage in my life where walk and not faint seems pretty good, but follow what goes on in the world is still exciting, even watching the birds. They inspire and soar effortlessly, seemingly defy limitations.

The big talk is fighting climate change, and the prevailing political belief is that rising CO2 levels is its major cause, so no expense is spared to find renewable energy in the form of wind power, but at what cost?

The Eagle has landed in aerie

on top of a windmill – that’s scary.

Doesn’t know she will die,

whacked right out of the sky

from rotating blades unawary.

The idea of wind farming is to create sustainable energy.

Will the population of eagles and other large birds be sustainable?

Image result for eagles and wind turbines

Eagles like to build their aeries on top of wind turbines, the highest structure in their territory.

It is estimated that the total bird kill by the year 2030 is going to be 1 million three hundred thousand birds. And that is if the Green New Deal is not implemented.

Is the large bird population sustainable even now?


This is a crane killed by a wind turbine blade. In parts of Ohio they have forbidden the turbines to run at night to protect a rare bat.

The allowable yearly limit for killing bald eagles by wind turbines  was upped from 1100 to 4200 per year on Jan 17 2017, still under the Obama administration. The allowable limit for golden eagles is still 0. If the bird-kill exceeds the allowance, heavy fines are imposed, but that is just the price of producing clean energy. in 2013 Duke energy paid a 1.9 million dollar fine for killing 14 golden eagles and 149 other protected birds. Recently, a US-based wind energy firm has been slapped with an $8m fine after at least 150 eagles died at its wind farms across eight states over the last 10 years. The company has also been given five years of probation. In April 2022 ESI Energy, a subsidiary of NextEra Energy, did plead guilty to three counts of violating the Migratory Bird Treaty Act. The company acknowledged the deaths of golden and bald eagles since 2012 at its farms in Wyoming, California, New Mexico, North Dakota, Colorado, Michigan, Arizona and Illinois, see more here.

Now for something completely unrelated: If you as a person poaches an eagle egg, see this picture

And it takes energy to produce energy. The cost of de-icing the average airplane is $1500. And that is without a helicopter.

And I am not sure about the former.

But there is still hope to solve the wind turbine bird kill problem. One potential solution is the vertical wind turbine:


It has a somewhat lower wind efficiency than horizontal, 3 blade wind turbines, but can produce electricity for about 4 c per kWh, about the same as horizontal wind turbines, so all is not lost. They do not kill birds, and can be made to function under wind speeds of up to 70 mph, but cut out speed is typically around 30 mph. This is a rapidly developing field, and requires much further analysis. A typical power output for a vertical wind turbine is 1 to 5 kW, 12 or 24 V output, versus the modern horizontal 3 blade wind turbines are 2 to 4 MW. Yet, the cost per kWh is comparable.

Another design, 300W nominal. Simple. eh!

Bur vertical windmills are hardly a new concept. These windmills are from Nashtifan, Iran. Dozens stand atop a wall in the windy city, not far from the Afghanistan border.

From a distance, they look like wooden turnstiles. But they are vertical-axis windmills constructed over 1,000 years ago from wood, straw and clay. And since the blades are arrayed on a vertical axis, energy is translated down the mast to the grindstone without the need for any of the intermediary gears found on horizontal axis windmills.

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Retired engineer, graduated from Chalmers Technical University a long time ago with a degree in Technical Physics. Career in Aerospace, Analytical Chemistry, computer chip manufacturing and finally adjunct faculty at Pennsylvania State University, taught just one course in Computer Engineering, the Capstone Course.

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