While environmentalists have long exclaimed the benefits of offshore wind turbines, new research suggests that ambitious plans to produce more offshore wind power must overcome several obstacles before they are realistic.
In 2015, the U.S. Department of Energy (DOE) submitted ambitious plans to expand the use of offshore wind turbine and produce substantially more wind power off land. The plan includes producing enough offshore wind power to be capable of meeting substantial U.S. electric-generating capacity, over 80 GW of offshore wind power, by 2050.
However, researchers from the Yale School of Forestry & Environmental Studies believe that this plan will be difficult to implement and is not as environmentally beneficial as previous thought.
One of the main reasons why offshore turbines have not been implemented on a wider basis is because of the substantial size of the turbines, which can be as tall as the Washington Monument with blades that have a diameter longer than a football field. Turbines also require powerful magnets that require about 2,000 pounds of rare-earth metals like neodymium for each magnet. To meet the DOE’s 2050 goal, 15.5 Gg if neodymium would be needed, of which 20 percent could be avoided by circular usage from decommissioned turbines if better recycling techniques and reusable magnets are developed.
Tomer Fishman, a former post-doctoral student at Yale School of Forestry & Environmental Studies (F&ES) and current lecturer at the IDC Herzliya in Israel said the majority of the world’s neodymium is mined in China, where costs are cheaper and less environmental regulations are in place. However, trade tensions in recent years between the U.S. and China have grown, adding a geopolitical obstacle to the offshore turbine plan that could “cause a bottleneck in the supply chain.”
The magnets are also built in Japan and then shipped to France where they are fitted into the turbines, adding two more countries into the mix.
Another issue with the DOE plan is that it does not account for the availability, or lack thereof, of neodymium, said the Yale researchers. In the past, the U.S. has mined neodymium at California’s Mountain Pass rare earth mine, but financial constraints and environmental concerns closed the operation several years ago.
The researchers found that a domestic program to build and install offshore wind power generating turbines would produce a complex web, where an overreliance on natural resources, regional demand and the recyclability of the turbine technology all become concerns.
Despite all the concerns, the researchers believe that it is possible to produce wind turbines efficiently, with the proper management.
“We can't be sure that offshore wind power will take off in the U.S., but there are a lot of positives,” Fishman said in a statement. “We've seen land-based wind power in the U.S. succeed, in spite of political partisanship. Though this has added layers of complexity, there's some promise there. What we're doing now is creating a roadmap to navigate the timing and scale of production. We're really starting from scratch, which give us the time to do it right and conduct more research. This is a good starting point.”
While wind production has tripled in the U.S. over the last year, only one small commercial wind farm off the coast of Rhode Island produces wind power offshore. In total, there are more than 56,800 wind turbines in 41 states and territories on land that generate more than 6 percent of the electricity in the U.S. This industry also supports more than 105,000 jobs and garners billions of dollars in private and public investment.
The study was published in Nature Sustainability.