A technology to keep fish away from danger
The problem
During their life cycle some fish species (Atlantic salmon, European eel, …) undertake yearly downstream migration towards the sea. During these downstream migrations fish encounter obstacles: industrial water intakes for cooling (nuclear or fossil power plants) or other industries which need to pump a lot of water (hydroelectricity). Many fish are drawn into these water intakes resulting in high mortality due either to asphyxia on filters or by direct contact with turbines blades.
Several types of fish barriers have been developed based on light, acoustic or electric stimuli. The goal of all these systems is to deter the fish from approaching the water intakes. To date none of these systems has demonstrated a consistent ability to deter all species of fish in a variety of sites and environments.
Our solution
In collaboration with the University of Liège, (Laboratory of Fish Demography, Belgium) and the University of Oslo (Norway), ProFish Technology has developed a new and original system based on infrasound emissions. It has been scientifically demonstrated that infrasounds can deflect fish with an efficiency close to 90%, on all species tested. The technology therefore demonstrates potential as an efficient multi-species fish repulsion system that can be widely applied on an international scale.
In practice
By equipping water intakes with one or more infrasound units (depending on the size of the water intake), migrating fish are kept away from the intake area. At water intake areas on hydroelectric systems, the deterred fish can be guided towards bypasses and spillways. Guidance systems for the silver eel is our main area of research for 2008.
The infrasound fish barrier can be coupled with an echo-detection system which automatically sets off the infrasound units when fish are detected approaching the intake.