At the end of the holidays, the alphabet thoroughly explored the wind power plant in Václavice. The ascent to the windmill was nerve-wracking and we filmed a very interesting video and took great photos in its bowels.
We stand on a hill near Václavice in the Liberec region, right on the border with Poland. There are 13 windmills that make up the tower Václavice wind park. Each of the towers is once independent power plant and is designed to capture as much wind as possible and produce as much energy as possible. We climb onto the roof of the gondola power plants number 7 at a height of ninety meters. I put on a climbing harness and listen to the briefing of our guide – engineer Mark Zikmund. I admit that there is a little soul in me.
Construction of a wind farm tower
Basics wind power plant they are made of monolithic concrete with steel reinforcement in the shape of a circle with a diameter of approximately 15 meters and a depth of two meters. Tube power plants it is composed of three steel segments with a circular diameter that taper in height. The bottom wall is 22 mm thick, the middle 20 mm and the top 18 mm. At the top, a gondola is placed on a rotating mechanism power plantsthat elongated booth to which a three-bladed propeller is attached. Power station with a tower height of 90 meters, the diameter of the propeller is roughly 100 meters, which means that the propeller blade extends above the tower by another 50 meters.
Transformer on the ground floor
We go up the stairs to the lowest accessible floor power plants. Below us is a transformer, where the generated electrical energy is transformed into a mains voltage of 22 kV and is carried by an underground cable 5.5 km to the transformer station in Hrádek na Nisou. When power station does not produce, the operating devices draw electricity via the same cable, on the contrary, from the transformer. There are also disconnectors upstairs to turn each one off power plant independently.
Main computer
We climb the ladder one floor higher. We are secured on the ladder with a self-braking carabiner on the rail. On the second floor is the operating panel of the control computer, where we read the current status on a small display power plants. The operator can also monitor the same data remotely on his laptop. We see energy production, weather and wind power. The wind blows at 4.4 m/s, which is less than 16 km/ha on the meteorological scale, it is a moderate wind. Power station it produces energy at about 20 percent of its capacity. It can remain in operation up to winds of 90 km/h, which is already the force of a gale. The light wind is favorable for us because the tower does not tilt.
Closet as an elevator
On the control computer, Marek requests access from the dispatchers and switches it off power plant. The propeller is stopped by simply turning the blades perpendicular to the wind. In addition to the computer, water-cooled semiconductor converters are also located on this floor. Power station although it produces alternating current, but with a different frequency than that in the distribution network. Frequency converters synchronize with the network, i.e. phase. We enter the elevator on the same floor. It hangs on two thin steel cables without additional securing, has the dimensions of a small wardrobe and can fit two people in it tightly.
Ábíčko climbed on the roof of the wind farm and inside •
Marek Holoubek, Zdeněk Ležák
In a gondola
After a nerve-wracking ride in the elevator, we get off at a height of about 80 meters and climb the ladder to the last floor under the gondola. Here, the rotating part with nacelle and propeller is mounted on the fixed tube. It is now secured by disc brakes. A few last steps and we are inside the gondola. It’s surprisingly spacious here. The nacelle weighs 70 tons and each of the three propeller blades another 8 tons. The center of gravity of the nacelle is exactly above the tube. The propeller shaft is connected to the planetary gearbox. In normal operation, it rotates at about 12 revolutions per second. The gearbox multiplies the rotation to 1202 revolutions per second.
View in the nacelle of the power station forward of the main shaft leading from the propeller to the gearbox •
Marek Holoubek, Zdeněk Ležák
I am sitting on the roof of the gondola of a wind farm more than 90 meters above the ground •
Marek Holoubek, Zdeněk Ležák
On the roof!
A shaft behind the gearbox turns the generator at the back of the nacelle. Above it is a massive cooling system. It is possible to walk along the sides of the machinery. In front is a hatch to the propeller. During maintenance, it is possible to climb directly into the propeller blades. There is a hatch in the floor at the back of the nacelle. In the event of an accident, we would be lowered right here on the chain of a small crane. We really don’t want that. There is another window in the ceiling at the back of the gondola, and through this we go up to the roof. Although we are secured with climbing harnesses, it is still a powerful experience. There is no railing and the depth threatens from all sides. With a pounding heart, I prefer to sit on my ass right away. But the view is breathtaking.
Václavice Wind Park:
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Václavice is the second largest and most powerful wind park in our country
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the largest wind park is located in the Ore Mountains near Kryštofové Hamry, it has 24 towers and a power of 42 MW (megawatts)
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the Václavice wind park was built in 2017 and is one of the most modern in the world in terms of generating electricity from wind
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each tower has a power of 2 MW and the total power of the park is 26 MW
