Phase 1: Environmental Research and Site Search
Ocean currents are located at the ocean surface and in deep water below 300 meters (984 feet). They can move water horizontally and vertically and occur on both local and global scales. The ocean has an interconnected current, or circulation, system powered by wind, tides, the Earth's rotation, the sun, and water density differences.
This constant motion in the world's oceans is called the global ocean conveyor belt, a combination of thermohaline currents in the deep ocean and wind-driven currents on the surface.
The volume of water transported by the global conveyor belt is equal to 100 Amazon Rivers or 16 times the flow of all the world's rivers combined.
Ocean currents are relatively constant and flow in one direction, in contrast to tidal currents. While ocean currents move slowly relative to typical wind speeds, they carry a great deal of energy because of the density of water. Water is more than 800 times denser than air. So for the same surface area, water moving 12 miles per hour exerts the same amount of force as a constant 110 mph wind
Consequentlyy, ocean currents contain an enormous amount of energy that can be captured and converted to a usable form. It has been estimated that taking just 1/1000th the available energy from the Gulf Stream would supply Florida with 35% of its electrical needs.
For ocean current energy to be utilized successfully at a commercial scale, a number of engineering and technical challenges need to be addressed, including:
Because the logistics of maintenance are likely to be complex and the costs potentially high, system reliability is of particular importance. At present no open-ocean current turbines are deployed in U.S. waters — this technology is truly in its infancy.