The University of Michigan has developed a novel approach to harnessing the slow moving energy at the bottom of oceans or large rivers. Called VIVACE or Vortex Induced Vibrations for Aquatic Clean Energy, the hydro system can produce energy with just 2 knots of water movement.
Oceans and rivers worldwide typically move at a clip of 3 knots or better, which gives VIVACE the edge over other hydro-electric systems that require 5 or 6 knots to work. The U of M VIVACE system is based upon the water flow over cylindrical objects.
When water hits the leading edge of a cylinder it forms a vortex behind, which moves the next cylinder. These whirlpools in turn swirl the cylinders that are connected to turbines that create electricity from the movement.
Some, like professor Michael Bernitsas, have likened this invention to the idea of fish swimming in the vortices of the fish ahead of them, using the movement of the water to propel themselves in similar fashion to professional bicyclers drafting one another. For years structural engineers who’ve worked on bridges, oil platforms and other large water structures have had to take these vortices into account and struggle with the movement.
The VIVACE turbines, on the other hand, take advantage of these renewable energy currents instead of fighting against them. The slow moving VIVACE turbines are also fish-friendly as won’t hurt the underwater life forms.
Current testing and development of the VIVACE system is being conducted on the Detroit River.