Fish friendly turbine
Due to its design with fixed runner blades, the DIVE-Turbine has no gaps and is therefore considered a fish friendly turbine. It is operating with very low runner speed in full load and reduced runner speed in part load. Thus, there is no risk of collision with rotating machine parts.
Characteristics | Advantages for the fish | |
---|---|---|
1 |
Maximum opening of runner blades in any operation point |
Low risk of collision |
2 |
No gap between runner blades and shaft |
No risk of pinch |
3 |
Gap between runner blade and cylinder <2mm |
No risk of pinch |
4 |
Very long runner blades |
Very low pressure gradient especially in combination with speed variable operation |
5 |
Number of runner blades can be reduced to three |
Low risk of collision |
6 |
Low runner speed esp. in part load |
Low collision speed Runner speed control in migration periods „SoftStart“: Slow start with low speeds |
7 |
Completely oil-free turbine |
No risk of lubricant leakage |
Speed variation and its effect on fish friendliness
Speed variation means that the runner speed of the turbine is reduced with sinking discharge (part load). The hydraulic effect of speed variation and the efficiency are comparable to Kaplan turbines with pitchable runner blades. The runner blades of the DIVE-Turbines are fixed to the runner shaft.
Regulation of Kaplan turbine and DIVE-Turbine: the runner speed of the Kaplan turbine is constant. The runner speed of the DIVE-Turbine is reduced in part load.
Regulation of Kaplan turbine and DIVE-Turbine: the runner speed of the Kaplan turbine is constant. The runner speed of the DIVE-Turbine is reduced in part load – the runner blades remain opened. The collision risk is sinking with the reduced runner speed, while for the Kaplan turbine the collision risk is significantly rising in part load, as the blades are closing.
Mortality risk at full load and part load for Kaplan turbine and DIVE-Turbine: The mortality of the Kaplan turbine is rising significantly in part load, because the runner blades are closing. The mortality of the DIVE-Turbine is sinking in part load because the runner speed is reduced. Due to the gap-free design of the DIVE-Turbine the mortality at full load is also assumed to be comparatively low.
The fish friendly behaviour of the DIVE-Turbine and specifically the positive effect of speed variation has been approved by practical research for fish length up to 25cm. More details on practical experiments will be provided on request.
Proof of fish friendliness
DIVE Turbinen GmbH & Co. KG is offering site specific fish friendly power plant design and fish friendliness consulting.
Further advantages of the DIVE-Turbine for fish friendly power plant designs
Component | DIVE-Turbine | State of the art Kaplan Turbine |
---|---|---|
Guide vanes |
Electronic drive Leakage of lubricants impossible |
Hydraulic drive and open hydraulic system Possibility of significant leakage of lubricants |
Sealing |
Contactless sealing, patented system free from wear and tear Abrasion is impossible |
Abradable seal Abrasion particles in the water |
Bearing |
Fully ecapsulated bearing Leakage of bearing oil impossible |
Bearing with classical sealing Leakage of bearing oil possible |
Bearing of generator |
ONE central bearing for turbine and generator (no gearbox) Minimum sound emmision |
Separate bearing for turbine and generator Ample need of lubricants High sound emmision |
Runner blades |
Fixed runner blades High overlap of blades also with three runner blades High efficiencies |
Pitchable runner blades with open oil hydraulic system No overlap of blades with 3 pitchable blades Low efficiencies due to missing overlap Leakage of lubricants and hydraulic oil |
Regulation |
Speed regulation Very low runner speeds in part load Fish friendly operation with low runner speeds in migration times (reduction of runner speed) |
Pitchable runner blades Critical, especially in part load when the blades are closing |
Partnering with Natel Energy for FishSafe™ Turbine Designs:
To achieve unparalleled fish safety without the need for complex fine screens or bypass systems we partner with Natel Energy and their revolutionary FishSafe™ technology. At DIVE-Turbine, we've championed fish-friendly hydropower for over a decade. Our commitment to reducing fish mortality led us to pioneer fixed blade propeller turbine technology with speed variation, significantly outperforming traditional Kaplan turbines. In collaboration with Natel Energy, a leader in fish-safe turbine design, we're integrating their revolutionary FishSafe™ technology with our DIVE-Turbine concept. This partnership ensures our turbines achieve unparalleled fish safety without the need for complex fine screens or bypass systems.
The result? The DIVE-Natel turbine, combining the expertise of both companies to deliver high-performance, maintenance-free turbines that prioritize fish passage safety. Reach out to learn more about this groundbreaking solution.