Sep 13, 2010
Science Scene - Tidal Power
Atlantis Resources Corporation's AT-1000 turbine is 22.5 meters (73 feet) tall and has a rotor diameter of 18 meters (59 feet) and weighs 130 tonnes. It will produce 1 MW of power from a water velocity of 2.65 meters (8.7 feet) per second.
"The giant turbine is expected to be environmentally benign due to a low rotation speed whilst in operation and will deliver predictable, sustainable power to the local Orkney grid." The turbine blades will only turn at a rate of 6 to 8 revolutions per minute.
The tidal turbine project is connected to a plan for a data center located in northern Scotland and intended to be powered entirely by tidal power. Tidal power offers a predicatable, reliable energy source. Water is 832 times as dense as air, making it possible to draw similar amounts of energy from a much smaller turbine unit. However, the harsh marine conditions that underwater equipment must face has made development of tidal energy a slower process.
Tidal energy generation currently needs headlands, islands, channels etc. to focus the power, accelerating it up to the cut in speeds of the current production tidal turbines (ie 2.6m/s in above article). These spots are the sweet spots where the first generation of tidal turbines will be tested. If they make it into mainstream volume production and become more efficient, more cost effective, etc. then they'll start working down to the lower speed sites of large ocean currents. Just the same way that the wind energy industry has developed. Tidal is currently 20-30 years behind wind energy industry but will potentially develop faster due to modern CFD, production technology and dual looming crises of peak oil and climate change. Tim Divett, PhD Student (Tidal Energy), University of Otago, New Zealand.