© Voith GmbH

Although electricity generated from hydropower already accounts for roughly a sixth of the world's electricity, there is still room to expand the role that natural waterways play in the power supply. Around 85 percent of run-of-river dams and weirs worldwide are not being used to generate electricity at the present time. Low heads at many sites are one of the reasons why this potential has so far been left untapped: Conventional turbine generator units need the water to have a certain head height in order to generate water economically. Yet even that is only feasible for conventional hydropower systems if relatively extensive construction work takes place. Another drawback is that large-scale construction activities frequently have negative consequences for the ecosystems in watercourses.

The StreamDiver® is designed precisely to avoid such adverse environmental impacts. Thanks to its innovative design, this low-maintenance turbine generator developed by Voith GmbH – a family-owned company based in Heidenheim in the southern German state of Baden-Württemberg – can be used to tap new sites for small hydropower generation. Due to its compact dimensions, the StreamDiver® can be installed in an existing weir system, so there is no need to carry out any construction work at the power plant other than installing the turbine generator unit itself. This makes installation more cost-effective, while also keeping the disturbance of watercourse ecosystems to a minimum. At the same time, integrating the turbine into existing transverse structures minimizes any visual impact on the landscape. The StreamDiver® has water-lubricated bearings and can therefore operate without oil or grease, ruling out any pollution of the water.

In 2014, the StreamDiver® earned Voith a place among the four finalists out of 300 entrants in the Large Companies category of the Innovationspreis der deutschen Wirtschaft (German Business Innovation Prize). Following year-long testing of the prototype, Voith has now received initial orders for this innovative concept. The StreamDiver® will go into commercial operation for the first time in Sweden.