The complicated future of offshore wind power in the US

The complicated future of offshore wind power in the US
The Block Island wind farm off the Rhode Island coast. Credit: Yale University

Over the past decade, wind power production in the U.S. has tripled, becoming the largest source of renewable energy in the country, the American Wind Energy Association has reported. There are more than 56,800 wind turbines in 41 states and territories, generating more than 6 percent of the nation's electricity, supporting more than 105,000 jobs and garnering billions of dollars in private and public investment.

While the vast majority of that production is happening on land—a rare exception being a small commercial wind farm off the Rhode Island coast—the U.S. Department of Energy (DOE) has laid out an ambitious plan to expand the nation's wind sector into offshore waters.

A new Yale study found that implementation will not be as simple—or, potentially, as green—as it may seem.

Writing in the journal Nature Sustainability, 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, and Thomas Graedel, a professor emeritus at F&ES, challenged the DOE's plan, focusing specifically on the challenge of supplying needed to build these offshore and the environmental, economic, and geopolitical issues at play.

Turbines like the ones off of Rhode Island, Fishman said, are enormous; they're as tall as the Washington Monument and have a blade diameter longer than a football field. These turbines also require incredibly powerful magnets that use the element neodymium, a rare-earth metal. And they require enormous amounts of it: roughly 2,000 pounds is needed to produce each magnet.

Nearly all of the world's neodymium is mined in China, where costs are cheaper and are less stringent, Fishman said. The magnets are built in Japan, then shipped to France where they are fitted into the turbines. Each step along the way, issues—like the current fractious trade relationship between the U.S. and China, for example—can "cause a bottleneck in the supply chain," he said.

The DOE plan also does not consider the availability of neodymium, Fishman said. The U.S. has mined neodymium in the past—at California's Mountain Pass rare earth mine—but financial troubles and environmental concerns brought operations to a halt several years ago.

Fishman and Graedel sought to address the potential issues in their paper, putting specific calculations to the plans laid out by the DOE. They found that creating a domestic program to build and install would create a complex web, raising questions of natural resource consumption, regional demand, and the recyclability of the turbine technology—in particular, the reuse of neodymium.

Fishman said their calculations could kickstart a realistic conversation of internalizing production of these turbines, which he believes is possible 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. "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," he added. "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."


Explore further

The U.S. is on the cusp of an offshore wind energy boom. Why aren't energy companies capitalizing on it?

More information: Tomer Fishman et al, Impact of the establishment of US offshore wind power on neodymium flows, Nature Sustainability (2019). DOI: 10.1038/s41893-019-0252-z
Journal information: Nature Sustainability

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Apr 03, 2019
"...A new Yale study found that implementation will not be as simple—or, potentially, as green—as it may seem...."

But it is still wildly by far greener than fossil fuel power so we certainly should still have it.
And why cannot neodymium be recycled over and over again for eternity?
Science may well even one day come up with a cheaper alternative to it.
All types of sources of power have their own special limitations and problems; it is just a matter of managing them to the best of our ability.

Apr 04, 2019
I just said there;

"Science may well even one day come up with a cheaper alternative to it."

and, guess what! I found out that, at least in principle, it almost already has! The trick is to make an electric generator that uses electric fields instead of magnetic fields. The same principle would also work with electric motors. So there already is a way, at least in theory, to avoid those expensive magnets!

Here is the link for that:
https://phys.org/...ple.html
"..."We have proven the concept of a new motor that uses electric fields rather than magnetic fields to transform electricity into a rotary force,
...
...could deliver major advantages in weight, material cost, operating efficiency and maintenance.
requirements.
...
the invention may first meet the market in the form of a generator for wind turbines,
...
The new design avoids the use of precious "rare earth" metals
..."

I am sure it is just a matter of when, not if, this will happen.

Apr 04, 2019
An alternative way to the above to avoid magnets is to design the electric generator to use a piezoelectric material instead of magnets (and it isn't to difficult to convert rotational motion to linear motion to make that idea work). But first we would have to develop a piezoelectric material, with sufficient power density and robustness, that is MUCH more energy efficient at converting mechanical energy into electric energy than any piezoelectric material so far invented. But, again, I am sure it is just a matter of when, not if, this will happen.

https://en.wikipe...ctricity

Apr 04, 2019
And there are other solutions yet. It is possible to use a generator that uses electrical excitation rather than powerful permanent magnets, and this is actually the favored design today.

Apr 04, 2019
This energy is free

Seeing as this is free renewable energy
by
adding a small lithium-ion battery
to
provide a small currant to the stator coils
that when this windmill stars rotating
starts the initial currant
where once up and running
this windmill keeps its starter battery charged up
this is not rocket science
after all
This energy is free

Apr 04, 2019
The biggest problem is the island dwellers living offshore in their multi-million dollar vacation homes who do not want to see these turbine blades whizzing around on their viewing horizon, witness what has killed wind power at other nearby locations of Martha's Vineyard.

Apr 04, 2019
Then there is climate change
Benni> The biggest problem is the island dwellers living offshore in their multi-million dollar vacation homes who do not want to see these turbine blades whizzing around on their viewing horizon, witness what has killed wind power at other nearby locations of Martha's Vineyard.

These windmills
calm the wind down wind
having a detrimental effect on the flora and fauna
just
wait till these global warmists
cotton on to this little snippet of information
these
global warmists
will
Have us living in caves yet

Apr 04, 2019
@humy; Interesting idea. You should look into it.

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