Ajakiri Ehitaja
Mart Arro, AS E-Betoonelement marketing manager

Since wind energy has become one of the most important sources of renewable energy, while also creating a completely new industry, it is important to understand how to collect wind energy most effectively. Until today, wind turbine towers have been mostly manufactured from steel; however, it is reasonable to use concrete for building more powerful and higher towers.

Mast

Many years ago, wind generators mostly served agricultural purposes, for example, grinding grain and pumping water through the energy they received. Many of these masterpieces made by man have survived to this day.

In the history of wind generators with both horizontal and vertical axes, as well as single, double and triple generators, have been tested.

How to get energy from the wind?
It can be calculated using the simplified formula P = KD2V3, where P is energy; K-factor; D-rotor diameter; V-wind speed. In other words, the energy from the wind is proportional to the rotor's diameter and the wind velocity cube.

Higher masts are reasonable to build from prefabricated concrete
The use of 2.5-3MW turbines in the field of wind turbines to be set up in the countryside is a standard, which presents a major challenge to wind turbines in the towers. For example, a 2.5-3MW turbine with a 100-meter diameter rotor will weigh about 150 tons.

The concrete structure provides the tower with sufficient rigidity for large turbines and long blades, helping to control vibration and secure the turbine without disturbing work. It is also easier to create a resonant-proof mastic solution.

In the case of metal towers, the sections are joined together with bolts and hundreds of bolts are needed to make one mast. Under constant vibration conditions, the bolts must be checked continuously.
The concrete tower elements to be erected are of high quality because they are manufactured under controlled conditions of the factory, of high quality concrete.

Access to wind farms is often limited, roads are narrow and curvy. During design, the size of the elements to be assembled is selected in such a way as to ensure easy access to even the hardest accessible objects.

Concrete is environmentally friendly material, well-accessible and at a relatively stable price, and its use helps to reduce the risks associated with the project.
For concrete masts over 100 m high, the concrete solution gives a significant price advantage in front of the steel, as the diameter of the mast and the thickness of the steel sheet used for its construction increase significantly.

A concrete tower 100 meters high weighs up to 1,500 tons
The E-Betoonelement product portfolio has two mast based on mounting solutions - 100-110m high concrete towers, in which the concrete section extends to the turbine or 100 to 150m high hybrid towers, a combination of concrete and steel tower.

The masonry of a concrete wind turbine is a truncated cone with a wall thickness of approximately 30 cm. This concrete masonry, in turn, is divided into cylinders placed on top of each other, approximately 10 to 15 m in size, which in turn is divided into segments or assembled elements.

The E-Betoonelement offers its customers a complete solution of concrete masonry from its design, finishing the tower assembly and after-tensioning at the construction site.