Fish lift
A device for getting over dam which can produce energy
Principle
To allow the fishes to cross an obstacle on the river, one carries out a device which catches them downstream of the obstacle and will free it upstream. A bow-net motorized by a crane crab allows this action.
Zone of capture
The cage is lowered in flow at the exit from the turbine. The section is calculated to offer a speed of water of 0.5m/s.
The spacings of the screen are chosen according to the types of fish concerned.
The installation consists of a fixed screen intended to prevent fish from circumventing the cage. A falling down mobile screen makes it possible to close the access to the fishing zone in the absence of the cage. This mobile screen is lowered by the weight of the cage during the downstroke and went up by a counterweight during the lifting up.
Zone of release
The crane crab will take along the cage to a zone upstream of the water intake, where the speed will be sufficiently low (~0.2 m/s) to allow the freed population to continue its migration upstream.
Electric production
A submerged turbine can ensure an energy production by turbinating the attraction flow plus, sometimes, the compensation water.