The Great Pulgoso (930008) writes "Norwegian energy group Norsk Hydro is to place giant floating wind turbines in the North Sea that will provide a reasonable, environmentally-friendly and economically feasible alternative to standard energy generation processes. The design uses a three-able tethered system, similar to the ones used in oil rigs, that holds a 200 meter tall steel tube with an attached turbine and three 60-meter-long blades. It expects to be able to use this technology on sites located 50-100 miles off shore, and with a depth of up to 500 meters. Images on the prototypes are on the link provided"
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