For the first time an archimedes screw is installed in Switzerland. The plant has a head of 1.15m at an average flow of 1000l/s. The picture above shows the site before the plant was built. At the right hand you can see the new railtrack bridge, at the spot covered by the shadow, the plant will be  erected.

At the picture at the left  you can see the Archimedes screw hanging on  the hook of a mobile cran. It shows the inlet of the screw. The nearest part is the case of the gear and generator unit. The screw has three helix blades at a diameter of 1600mm and weights 5800kg. The outlet of the screw can be seen in the picture at the right. The tube is not all around, this way the circular shape can by made more accurate.
 

The screw is put in place. All the concrete walls tower only 5cm above the upper water level, so during high-water, the water has a free running area.

The screws tilt angle of 22°

After putting the screw in place, the floor of the plant house also has been installed. The house will, assisted by a cabinet around the gear and generator unit, absorb the sound. It is not that loud that it would actually be needed, but the neighbors are very sensitiv and I don't want troubels. On top of the screw you may see the gear and generator unit. The water in front of the microhydro is not dammed up yet because there is still a lot of work to do. Righthand you see the bypass channel, in the middle the screw channel. At left there is enough free running area for high-water.

Many thanks to the owner of the plant Thomas Köhli for providing the information and the photographs. If you would like to contact Mr.Köhli, you can reach him through e-mail by clicking here.