Vertical Axis Wind Turbines

[Abramelin]

Promoters of green energy go crazy over wind turbines.

Personally I don't like their preferred wind turbines, the socalled Horizontal Axis Wind Turbines (HAWT).

Why? Well, they need a lot of space, they spoil the horizon, and they are deadly for birds. And German scientists even think these HAWTs are responsible for the general decrease of insect populations.

To show you the alternative, the socalled Vertical Axis Wind Turbines (VAWT), here a number of videos to show you what I am talking about:

https://m.youtube.com/watch?v=RyMraF4DXFI

https://m.youtube.com/watch?v=Tzf4xrKUaIk

https://m.youtube.com/watch?v=vCcHKikC8I4

The best? https://m.youtube.com/watch?v=l3sSCwi4VJA

The argument against VAWTs is that they are less efficient than the preferred HAWTs. But it appears to me that it is only a question of time before that problem will be solved.

[Piney]

What the Hell does a Dutchman know about windmills????? 

[Abramelin]

The Spaniards have an even better idea: skybrators. I saw it on Dutch television a few days ago, and a couple have been installed here. But I forgot the name, and you can imagine the results Google came up with when I tried all kinds of things that 'vibrate' ...

Ok, first some text that went along with the video:

 

He is nicknamed the skybrator, and although the Spanish start-up with wind turbines without Vortex Bladeless propellers is the target of jokes, he himself coined the slogan The bigger, the better. it gets kinetic energy from the wind - just another way. The design captures gusts of wind, which have certain frequencies depending on their speed. And if the gust frequency coincides with the frequency of the structure, the energy is absorbed by the pillar after it vibrates due to its aeroelastic properties. The prototypes are still grounded. They measure 2.75 meters and their power is only 100 watts. However, they weigh less than 15 kilograms and the company promises less weight than with conventional wind turbines for future larger types, by 80 percent. In addition, the 140-meter-high Skybrator should have an output of up to one megawatt of energy. And just for its construction, the company is now looking for an industrial partner with only six employees. In addition to even greater environmental friendliness, lower costs also promise this. Our turbines can be installed everywhere, but the optimal location is next to the road, where they connect to the existing infrastructure. There is no need to dig anything, lighting poles and their cables are enough for direct connection to the network. The trail is slight, and the roads are not exactly lookout points. The Skybrator holds two magnets in the ground, forcing it to oscillate even in the weakest weather conditions. Without the engine and turbines, it works even at lower temperatures, much longer than a normal mill, does not make such noise and does not need thorough maintenance, including lubrication. In addition, it does not endanger birds. Propellers are said to die more than 500,000 a year due to propellers, which is still a fraction of the environmental impact of fossil fuel power plants.

 

[DarkHunter]

The efficiency issue is not something that will go away regardless of any level of research or development.  

Essentially the efficiency of any wind turbine can be calculated from the Bernoulli equation in fluid mechanics.  It has been found that the highest possible efficiency that can be gained from a wind turbine in a theoretical setting is approximately 59% and it's called the Betz limit.  The 59% limit is not practically possible, it's just a ceiling that can never be breached kind of similar to how its impossible to go faster then the speed of light.  For practical designs the maximum efficiency of each has also been derived from the Bernoulli equation and for 3 bladed horizontal axis wind turbines its approximately 49% while for vertical axis wind turbines its approximately 15%.  

There is just simply no way to get the efficiency above 15% due to physical laws.

As for birds wind turbines kill very few birds especially new wind turbines.  When wind turbines were first coming out there was a slight problem with high rpm and low torque wind turbines killing some birds but for the past few decades wind turbines have been low rpm and high torque.  

[Abramelin]

It's birds and bats:

https://www.evwind.es/2020/10/01/the-realities-of-bird-and-bat-deaths-by-wind-turbines/77477