I have always seen the wind induced vortexes as a problem – they create vibrations in the tower, that in some cases can start to resonate with the eigenfrequencies (the natural frequencies of the structure) and in the most extreme cases even collapse.
The existence of such vibrations is one of the reasons why it looks like that steel towers for wind turbine have reached their maximum height. At around 100 – 120 meters they start needing dampers and other anti-vortex solutions during installation and for the operational life.
What I was not aware of is that there is a Spanish start-up trying to develop a “bladeless turbine” which exploits this phenomenon to produce electricity.
I have some doubts on the idea of a “bladeless turbine” (I suspect that a wind turbine has, by definition, a rotating part). However the concept developed by the folks at Vortex is for sure very interesting.
The Vortex Tacoma (this is the name of the industrial version under development) is expected to have a height around 3 meters, a weight around 15 Kg and a rated power output of about100w.
Currently smaller scale prototypes are available and the target date for launch of the full scale production is end of 2020.
It looks like a big cylinder oscillating when the wind blow. I also see that they selected the same combination of materials as wind turbines blades (resins reinforced with carbon fiber and/or glass fiber), while for the bottom section anchored to the ground they have selected a carbon fiber reinforced polymer due to its resistance of cyclical loads.
If you wonder how does it generate energy it is with an alternator system with coils and magnets. The cool part is that, unlike wind turbines, you do not have gearboxes, shafts or any other rotating element. The benefit is not only less maintenance but also a noiseless operation.
An additional interesting characteristic of this technology is that many machines can be clustered together in a narrow space. Standard wind turbines have a distance of hundreds of meters from each other to avoid the wake effect (basically the turbulence in the wind caused by the turbine itself). The wake effect can have an impact not only in the energy production of the turbine but also on its lifespan, shortening it due to the demanding operational conditions.
On the other hand the bladeless solution thrive on turbulence so you can pack more Tacoma Vortex together in what would probably look like a forest of artificial trees.
Another very cool feature of this machine is its ability to change its rigidity to adapt it to the characteristics of the wind. Different environmental conditions will request a different setup from the vortex in terms of mass distribution and rigidity. According to the website of the developer the machine will be able to automatically “tune itself” in order to maximize the oscillations.
How much do they cost and can I buy one
Very low swept area. Swept area is usually necessary. More area gives more power potentential. Take a look at test of all types if turbines, you will find the most cost effective ones are as large as you can make , and conventional horizontal axis designs.
I find this article most interesting.
Question how close can the columns be to each other and still be efficient?
Can we build a colonnade of these resembling Greek architecture?
Would not only be efficient but also esthetic.