Wind turbines are being built all over the world as part of the global energy transition. But there is not enough space for them everywhere. At the same time, nature conservation often puts a damper on projects. Students at the HTWG Konstanz University of Applied Sciences - Technology, Business and Design therefore want to rely on small windmills to generate green electricity. In their 'Sailwind 4' project, the young engineers are planning to recreate a Greek sailing windmill, the oldest known device for harnessing wind energy - today a cultural asset in the Mediterranean region from Portugal to France.

While 3,000 years ago the mills powered water wheels for grain cultivation, in future they will generate green electricity using a generator. The advantage: thousands of mills already exist and can be retrofitted as mini power plants for green electricity.
Igus is enthusiastic about the compact wind power plant. "We have the goal of being CO2-neutral with buildings and production by 2025, but at the same time we are also thinking beyond the boundaries of the company. That's why we are supporting the Sailwind 4 project with 10,000 euros and providing the students with free components for the construction of the innovative windmills," says Tobias Vogel, Managing Director of Bearings and Linear Technology at Igus.

If everything goes according to plan, the students will start building the first windmill in October. Visually, it will retain the typical characteristics of the historical model: the cylindrical mill body and the tapered roof construction. The same applies to the blade rods, which rest on the rotating main shaft. However, the engineers will attach high-tech sails to them and connect the shaft to an electricity generator. At a wind speed of 14 m/s, the windmill should then be able to generate 5 kWp of electricity - enough to supply a restaurant, hotel or small business. The small wind turbine could also be combined with a photovoltaic system and a battery storage system. "We have set ourselves the mechatronic task of fully automating the operation of the sailing windmill, as with large wind turbines," explains Prof. Dieter Schwechten, who initiated Sailwind 4 together with Prof. Ditmar Ihlenburg. The components from Igus come into play in this automation, for example linear guides for the motorized trimming of the sails, as well as a slewing ring bearing for the rotor and plain bearings made of high-performance plastic.