Renewable Energy From Slow Water Currents
We can use slow moving ocean and river waves for a new, reliable and affordable alternative energy source. A University of Michigan engineer has developed a device that acts like a fish that turns the potentially destructive vibrations in water into clean, renewable energy. This machine is named as VIVACE ( Vortex Induced Vibrations for Aquatic Clean Energy). It is the first known device that could draw energy from most water currents around the world, according to a statement from the University of Michigan. “There won’t be one solution for the world’s energy needs,” VIVACE developer Michael Bernitsas, a professor at the U-M department of naval architecture and marine engineering, said in the statement. “But if we could harness 0.1 percent of the energy in the ocean, we could support the energy needs of 15 billion people.”
YouTube: VIVACE Concept | More Videos
VIVACE can work in flowing water moving slower than 2 knots, or about 2 miles per hour. Here it should be noted that most water currents are slower than 3 knots, while turbines and water mills need an average of 5 or 6 knots to operate efficiently. VIVACE doesn’t need waves, tides, turbines or dams. It’s an unequaled hydrokinetic energy system that relies on “vortex induced vibrations.” Think like a fish not like a bird, say researchers of the University of Michigan. Because in water, nature has invented a different strategy for natural swimmers. If we observe the movement of a tiny sperm or a giant whale, we will see that they generate vortices (or little whirlpools) that they push off of to propel themselves forward. Michael Bernitsas of the University of Michigan, realized that these same vortices could be used to drive a generator. He and his colleagues have invented VIVACE whose cylinders oscillate up and down in moving waters. “This device works naturally in the marine environment,” says Bernitsas.
Bernitsas’ team has developed a working prototype in their lab. The spring-supported cylinder moves up and down in a tank of moving water. As water bangs into the cylinder, this action induces turbulence which transforms into a vortex. The vortex eventually rolls off the back, giving the cylinder a little push as it goes. The next vortex that forms will spin in reverse and give a push in the opposite direction. These opposing forces cause the cylinder to vibrate up and down. The high density of water, makes the vibrations about 800 times more energetic than they would be in air at the same speed. Due to this, the VIVACE system can produce three to 10 times more energy from a given volume of moving water than tidal turbines.
Bernitsas and his team have tried to duplicate the roughness of fish scales on their cylinders because a rough cylinder surface could increase the power output by 40 to 70 percent compared to a smooth surface. Bernitsas is also impressed with fish tails. His team has begun to experiment with passive tails that could keep vortices from interfering with each other.
Currently Bernitsas’ group is working with the U.S. Navy to install two VIVACE systems in the next year: one in the Detroit River and another in an ocean environment somewhere.
Although the production of VIVACE systems in commercial plants is still a future dream, the cost of electricity from a mature VIVACE installation would be roughly 5.5 cents per kilowatt-hour, which is similar to the current price of wind generation. Roger Bedard, EPRI’s ocean energy leader is of the opinion that with the passage of time, slower tidal passages will become economical.
- Visit Vortex Hydro Energy
Related posts:
- Renewable Ocean Energy: Tides, Currents, and Waves
- Ocean Renewable Energy Coalition
- Tidal Energy Industry Boom
- New Sponge-like Gas Storage Material
- Clean Energy from Flowing Waters
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January 9th, 2009
This is really nice article which i have read these days…but how about the maintenance of this in the sense as it is marine and it seems the installation cost?? to b high
January 9th, 2009
Dear Prof. Michael Bernitsas,
Congratulations for inventing amazing technology to generate energy from slow moving water mass.
I am sure this will change many equations in energy generation in near future.
I would love to receive more info. and license to go for this technology in India for benefit of rural population.
Ravi Soparkar, Pune, India
renewableenergy[AT]in.com
January 14th, 2009
This sounds like another good idea if it can be realized in a financially feasible way. One part of the article that worries me is the mention making enough power for 15 billion people. Overpopulation is the root cause for every environmental issue we face today. We, as a species, should create more renewable energy resources and less people.
Daniel G.
Norman Oklahoma, USA
January 17th, 2009
@deepthi - I agree with you that the installation costs would be very high, but the initial investment in all new forms of energy are high. In my humble opinion, the long-term benefits greatly outweigh the short-term costs.
January 21st, 2009
Finally, my thought is that you could go further of shore and tap into the larger oceanic currents like the gulf stream in the Atlanic etc. This has been on my mind for months and finally someone is on the right track as your system seems to be very fish friendly. If your estimate of 15 million is only the energy washing ashore think of the potential in the larger oceans, they are all moving.
Dale
January 25th, 2009
Congratulations on the invention. I hope to see it out in the world soon.
But to what “Daniel” said. Im sorry sir but over population is not a fact it is a mere estimate. If you really took the time to think about it there is 24,000,000,000(24 billion) sq. feet in Jacksonville, Florida alone. If you think about that and the fact that the average person takes up about 4 feet each then you would see that everyone in the world could fit into Florida!! (not comfortably, but they would fit) In truth the only reason that the earth would seem overpopulated is because all the nice places to live is were everyone moves… (Hawaii, New York, Tokyo, Sydney, Paris, San Fransico) And have you ever driven across Texas or Montana or even Nebraska? There is so much land out there its not even funny. And the only reason people aren’t there is because they want to live else where.
March 23rd, 2009
Very good tech. indeed, but seems as if the fixed cost might go high. there is a vast source of slow moving water areas, and if this tech is a success, definitely a huge amount of deficit can be handled.
May 10th, 2009
@L Maniot
Overpopulation refers to the Earth’s capability for supporting human life, not space. Already we are reaching the sustainable levels. If we look at land area, the earth could very easily support hundreds of billions of people, however where would we grow food? How would we rotate crops? It would be nice to move everyone into a contained area but it just is not feasible.