Everyone knows the enormous development obtained by the generation of wind power, and how it has been transferred to the sea to better take advantage of the more stable winds that circulate on the sea surface.
As it is an activity with a great future, some have looked for alternatives that simplify the designs and make them more robust, and have tried vertical wind-generator turbines. It is the vertical axis that rotates and generates electrical energy.
That is what the Swedish Company Sea Twirl has done, which has been testing a 30 KW prototype for several years, and will soon test another 1 MW one. (it is the S2x model), which protrudes 55m. above water, it is 80m. underwater, and the blades with a length of 40m. and with a turning diameter of 50m.
The power generator is a little above the surface of the water by means of a float that also acts as a counterweight to the mast, and is anchored by several cables to fix it above the sea.
By having a vertical mast, the rotation of the blades occurs independently of the direction of the wind, and since everything is on the same axis, there are produced less torsional forces, which helps to improve the duration of the rotation bearings. And that also simplifies the design, making it more robust and durable.
This type of wind turbines protrude from the water much less than the horizontal type generators, which also reduces their visual effect in the distance,
A video can be seen at: https://youtu.be/wMftW4ldguI
The manufacturing company assures that its design is simpler and less complex than the current ones, with fewer moving parts, so the costs are also lower than those of current generators.
And being simpler, it is more robust and is expected to have fewer breakdowns, generating less maintenance costs. Everything seems very positive, but we will have to wait for real data from the installed prototypes to draw definitive conclusions.
And there are also other companies like Sandia, Darrieus, etc… that are developing vertical axis wind turbines. And all claim to be able to lower costs and make the operation of the machines more reliable, which would lower both purchase costs and subsequent maintenance costs.
It will be necessary to see the real data of the prototypes that they put into operation, in order to make decisions with objective data.
The idea sounds good and could mean a change in the future of wind turbines. Time will tell.
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