The amount of wind blowing off the California coast has high potential. Lawrence Livermore National Laboratory atmospheric scientists are working with a Norwegian company to leverage that wind as a valuable energy source. LLNL has signed a memorandum of understanding with Sway, a renewable energy company that has developed floating towers for placing wind turbines in deep water. Though California has not yet approved offshore wind turbines, Sway has launched a prototype off the coast of Norway on June to demonstrate how the system could work in the Pacific Ocean.
Towers for offshore wind turbines typically sit in water as much as 30-m deep and are anchored to the ocean floor. Based on technology that was originally used for deep-sea oil drilling, Sway has developed a floating tethered tower that allows siting turbines in water 60 to 400-m deep.
“California has an abundance of deep-water wind resources, so this is an opportunity for the state,” said Nalu Kaahaaina, LLNL’s Low-Carbon Energy Program leader. “This technology is clean, reliable. and even more consistent than traditional onshore wind turbines.”
Power generation from offshore wind turbines is significantly higher than from units onshore. “The wind blows all the time at some offshore wind resources in California,” says Roger Aines, LLNL’s Carbon Fuel Cycle Program leader. “If Sway has success in Norway, the technology could be useful in California.”
Lawrence Livermore has a history in atmospheric studies. Its scientists will provide their expertise in wind energy to help launch the project internationally, nationally, and regionally. For instance, the Laboratory works on numerical weather prediction models to predict power generated by the wind, so that wind farms operate to max potential.
Predictive time frames range from an hour to days ahead of time. LLNL scientists plan to include ocean circulation and wake-turbulence studies to determine the most suitable sites for deep-ocean wind farms. Using this data, Aines says wind operators can find the best locations for wind farms, on or offshore. In California, the only option for offshore wind turbines would be in the deep ocean, away from coastlines.
Offshore wind projects in the U.S. must strike a balance between technological and economic challenges and adhere to more demanding environmental requirements to be successful. The latest generation of offshore turbines is equipped to meet the challenges of the ocean environment and weather extremes, which can limit access for routine maintenance. According to the American Wind Energy Association, wind energy made up 2.3% of U.S. electricity by the end of 2010, up from 1.8% a year ago.