Swedish automaker Minesto is developing what it calls it's "Deep Green" technology that are underwater kites tethered to the ocean floor that could produce continuous energy from tidal flows in which a single Deep Green turbine could produce up to 500 kilowatts of electricity. As the tides are much more regular than winds so the energy produced would be less erratic and variable.The kites have a 12m (almost 40 ft) wingspan and these kites would remain at least 20m (66 feet) below the surface, to prevent conflicts with ocean navigation and minimize visual impact. Tidal flow as low as 1.6 meters/second can be used to create the lift necessary to move the underwater kite.
Since the underwater kite is anchored to the ocean floor, it is able to move at much faster speeds, that makes the turbine more effective, as it traverses back and forth in order to generate electricity, although wind-based deepwater offshore power systems are much difficult to install and operate, Deep Green tidal kites would be well suited for installation in deep waters. Furthermore, the underwater “Deep Green” kites are much lighter and easier to install than the equipment needed for other deepwater generation systems. Deepwater generating systems have the additional expense and technical hurdles of transmitting the power over a greater distance but the higher efficiency and more consistent generation offered by these tidal kites could offset those drawbacks.
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