Technology & maintenance
Power generation is made possible by a drum (rotating cylinder) with a casing pipe that is seamlessly welded to the screw blades. In contrast to conventional hydrodynamic screws, the Hydroconnect hydrodynamic screw is mounted by means of the patented belt capstan or rolls on the outer shell.
The flow of water from the exiting headrace and the central luring current are used to guide fish wanting to reach the upper level to the inner fish lift. As soon as they swim into the entrance, which reaches down as far as the river bed, they are transported gently upwards in the constantly filling water. The fish end up at the upper level via a fish discharge chute.
The water transported to this upper level is ready once again for reuse by the plant or alternatively for the fish to make their way down.
Installation sites and possible uses of the Hydroconnect hydropower screw are:
- existing dam stages
- existing power plants for fish ascent and descent incl. energy production
- run-of-river hydropower plants for fish ascent and descent
- diversion power plants as a residual water machine
- water pumping station for irrigation and/or storage power plants
- industrial process water (paper and steel industry)
- supply and drainage of sewage treatment plants (municipal + industrial)
- Hydroconnect uses different types of ball bearings for the belt or roll mount.
- 3-month lubrication intervals are reasonable
- Belt mount: Designed for ca. 100,000 hours under full load
- No maintenance work after flooding if the underwater protection or seal is selected
- Lubrication: Use biologically safe lubricants
The space that is required is determined as follows: screw diameter + inside clearance 1000 mm total (i.e. 500 mm per side). See drawing. Protection in the bottom water area is a good idea, because that way the system can be drained in the event of high water and for maintenance work.
- Frequency converter switch
- Disc brakes (overspeed is prevented)
- Sealable intake gate
Application of the brake in the event of a power outage
The process from the first contact up to an operational hydropower screw and the approval:
- (Feasibility) analysis and evaluation of the transverse structure, water quantity – on-site inspection
- Rough concept / recommendation
- Detailed concept / technical planning of the individual installation situation
- Financing / funding advice for the realisation of an EU WFD-conforming fish bypass including electricity generation
- Official approvals for your project
- Creation of the structure (by the customer), production of the hydropower screw with double rotating cylinders
- Delivery, assembly, trial operation
- Training of the responsible people on-site
- Maintenance, service, possibly updates
- Monitoring by a well-known institute (qualify for funding)
Environment & fisheries
Fish swim actively against the current into the screw and are transported gently to the headwater. For outward migration, fish and microorganisms simply swim (drift) downstream with the headrace water. At many (large) locations, an additional luring current can make it easier to find.
There is a current leading to the screw in the bottom area of the entry, which is very well suited for fish and pentos that are weakened from swimming. (Also see Technology)
Even in floods, fish are not simply swept away, rather the population normalises again after a short amount of time. Fish that are swept away in a flood can return to their original locations at any time. That way the population can recover again quickly.