Gravitation water vortex power plant

A water vortex power plant, also gravitation water vortex power plant ( GWWK ) called, is a small hydroelectric power plant, which is suitable for the generation of hydroelectric power from a flow of 50 liters of water per second for small height differences of 0.5 to 3 meters fall. The technique is based on a ( round ) pool with a central drain. About the outflow, a stable water vortex is formed which drives a special rotating at 16 to 22 revolutions per minute of water turbine.

Operation

A balanced water vortex forms in a rotationally symmetrical vessel via a drain hole in the center of the vessel bottom out. For the technical usability of a stable and symmetric eddies sought by free flow vortex center, which drives a slowly rotating turbine.

In the ideal case, a potential vortex, the tangential velocity increases continuously in the direction of the vortex center. Prerequisite for the formation of a stable vertical axis of rotation is gravity. Water outflow is minimized, when the diameter of the dam is substantially greater than the diameter of the drain.

Ecological impact

Proponents of water vortex power plants argue that because of the intense water aeration by the gravitation water vortex in the rotating basin of a water vortex power plant an ideal habitat for aquatic plants, small animals and fish is created. Thus the walls of the round impoundment are overgrown after a short time with spring moss, between which numerous amphipods and caddis fly larvae settle.

Critics such as the WWF and others point out that water vortex power plants are a barrier which preclude the revitalization of rivers, and that the continuity of slowly floating fish species has not been proven. Zotlöterer proceeds from a fish patency, such as using a fine-mesh fish and therefore dense grid, which was a few meters upstream inserted before the rotation pool in the inlet channel and fish, such as octagons and trout had, had been shown. That the water vortex power plant for numerous fish species is ecologically consistent, has now been confirmed by an independent investigation by the University of Agricultural Sciences, Vienna.

The cooperative water vortex power plant has run at its pilot and test power plant " Dr. Bertrand Piccard " has long been independent studies on this subject, which are constantly expanding and contain very positive interim results.

Regardless of the suspected partial patency remains the water vortex power plant, a large intrusion into the watercourse, which is a very low efficiency in a bad relationship for the electricity produced. Franz mill has measured in experiments at the Technical University of Munich peak efficiencies from 31 to 48.5 %. This results in system efficiency ( transmission 0.94; generator 0.86 ) from about 25 to 39% depending on the ratio of flow to building size. The higher values ​​are obtained at very low flows, or they require very large structures at a fixed flow rate.

Application

The concept of energy from a water vortex that forms above the outlet of a water reservoir, is used in various devices. So based one in 1968 by the American Kenard D. Brown ( 1968 / U.S. Patent 3,372,905 ) and patented in 1996 by Australian Paul Kouris device on the production of energy from such a water vortex with high head and with the help of a long intake tube.

The Austrian engineer Franz Zotlöterer realized a gravitation water vortex power plant with a patented, easily spiral rotational pool ( 2003 / Austrian Patent AT412363B. Patents AT413579B. , And 2007 / Swiss Patent CH699133. ) And the patented Zotlöterer turbine (PCT Patent WO2011051421. ), Which at low drop heights from 70 cm and water volumes from 50 l / s can be used as Laufwasserkraftwerk.

This relatively slow rotating turbines are used (about 20 revolutions per minute) that are consistent for small floating debris, sediment and fish. In collaboration with the University of Applied Sciences Northwestern Switzerland University of Applied Sciences has been trying to further optimize the rotor to harvest more energy from the vortex. This turbine, which is to take advantage of the vertical currents, but only has an efficiency of 50 %, because it gravitation water vortex is limited in its opportunities for development and the upcoming for the turbine torque decreases.

In a pilot plant, which was built with a pelvic diameter of 5.5 m, a height of 1.5 m and a flow rate of 0.9 m³ / s in the Austrian top -Graf village in 2005, will be the new Zotlöterer turbine at an unconfirmed and achieved undoubted turbine efficiency of 80 % 10 kW of electrical power and 60,000 kWh / a. The rotation frequency of the turbine is 33 min-1 (0.55 Hz). Other systems have existed since 2009 in Switzerland (at the Suhre in Schöftland ); electric power up to 10 kW, annual production up to 35,000 kWh / a or electricity needs of about 9 households. Still more are planned or are clarified. Since 2011 is in Austria in Carinthia at Wimitzbach with 2 × 3.5 kW and 27,000 kWh / a and since the end of 2011 in Germany in Winterberg / Sauerland with 1 × 3.8 kW. However, were evident in Winterberg typical but low noise ( 60dB ) of the transmission. A built in Indonesia in 2007, this is not yet in operation for regulatory reasons.

For larger heads and flow rates significantly more power can be gained (2.5 m, 10 m³ / s: 150 kW). For powers greater than 150 kW water vortex power plants are inefficient because they have a smaller standard capacity (ie a lower overall efficiency ) than conventional small hydro power plants.

Problems

Unfortunately, all known scientific studies show efficiencies below 50% and also independently published by the manufacturer Zotlöterer popular scientific articles clearly show the problems of this technology. For example, since 2009 in the Swiss Schöftland (see above) existing plant in the article by Matthias Daum in the magazine is " TIME " examined in detail. In the article, even the operator of the plant, Heidi Zumstein and Andreas Steinmann show initially disappointed with the efficiency of their investment. "He was only 30 instead of the promised 60 percent. Two thirds of the energy contained in the water, the creek went literally down. Nowadays, some technical improvements later, the efficiency is 42 percent. A new rotor is soon half of the hydrogen energy help convert it into electricity. " Scientific trials and resulting article as the investigations by Franz mill, Christoph Rapp and Oliver Mayer also have efficiencies from 31 to 48.5 % (see above)

Awards

• 2007: Energy Globe Award Carinthia
• 2010: Energy Globe Award Austria Lower Austria in 2010 and 2010 ( special category Inventor)
• 2011: Watt d' Or 2011 in the category Renewable energy for river restoration with water vortex power plant in Schöftland, awarded by the Swiss Federal Office of Energy