4: Floating Wind Farms
While wind energy isn't necessarily wacky in and of itself, you've got to admit there's something a little out there about a giant wind farm floating in the middle of the ocean. If you plan on visiting Norway in the coming years, you may catch a glimpse of these towering turbines spinning off the country's southwest coast from your airplane window.
Offshore wind farms can only be placed in water up to 131 feet (40 meters) deep, but floating wind turbines are a relatively new concept designed to take advantage of the high-speed winds located farther out at sea. Since they don't have to be physically buried in the sea floor, floating turbines can be placed in water as deep as 2,297 feet (700 meters). Their ability to be situated far from shore is a large part of their appeal, since many offshore wind projects face staunch opposition from people worried about altering their multimillion-dollar oceanfront views.
Even more appealing, perhaps, is the greater energy capacity of these floating turbines. While winds moving across land may only average speeds around 13 feet (4 meters) per second due to obstructions like hills and trees, winds blowing over the open ocean reach speeds at least twice as fast. That makes a big difference since wind blowing at 33 feet (10 meters) per second generates five times as much electricity as wind blowing 16 feet (5 meters) per second [source: Economist]. Some reports suggest that wind farms could provide up to 15 percent of the world's future energy needs [source: Jacquot].
StatoilHydro, a Norwegian energy company, has plans to construct the world's first full-scale floating wind farm in 2009. According to the company's Web site, each turbine will weigh a total of 5,842 tons (5,300 metric tons). The turbine will stand 213 feet (65 meters) above sea level, while a 328-foot (100-meter) floating element under the surface will be attached to three anchors to keep it stationary. The 262-foot (80-meter) turbine blades should be able to produce 2.3 megawatts of electricity [source: StatoilHydro]. If everything goes as planned, Norway will have a significant energy source, but coastline dwellers will be none the wiser.
