California is planning floating wind farms offshore to boost its power supply – here’s how they work

Equinor’s Hywind Scotland became the world’s first floating wind farm in 2017. Øyvind Gravås/Woldcam via Equinor

Matthew Lackner, University of Massachusetts Amherst

Northern California has some of the strongest offshore winds in the U.S., with immense potential to produce clean energy. But it has a problem. Its continental shelf drops off quickly, making building traditional wind turbines directly on the seafloor costly if not impossible.

Once water gets more than about 200 feet deep – roughly the height of an 18-story building – these “monopile” structures are pretty much out of the question.

A solution has emerged that’s being tested in several locations around the world: making wind turbines that float. In fact, in California, where drought is putting pressure on the hydropower supply and fires have threatened electricity imports from the Pacific Northwest, the state is moving forward on plans to develop the nation’s first floating offshore wind farms as we speak.

So how do they work?

Three main ways to float a turbine

A floating wind turbine works just like other wind turbines – wind pushes on the blades, causing the rotor to turn, which drives a generator that creates electricity. But instead of having its tower embedded directly into the ground or the sea floor, a floating wind turbine sits on a platform with mooring lines, such as chains or ropes, that connect to anchors in the seabed below.

These mooring lines hold the turbine in place against the wind and keep it connected to the cable that sends its electricity back to shore.

Most of the stability is provided by the floating platform itself. The trick is to design the platform so the turbine doesn’t tip too far in strong winds or storms.

An illustration of each in an ocean, showing how lines anchor it to the sea floor.
Three of the common types of floating wind turbine platform. Josh Bauer/NREL

There are three main types of platforms:

  • A spar buoy platform is a long hollow cylinder that extends downwards from the turbine tower. It floats vertically in deep water, weighted with ballast in the bottom of the cylinder to lower its center of gravity. It’s then anchored in place, but with slack lines that allow it to move with the water to avoid damage. Spar buoys have been used by the oil and gas industry for years for offshore operations.
  • Semi-submersible platforms have large floating hulls that spread out from the tower, also anchored to prevent drifting. Designers have been experimenting with multiple turbines on some of these hulls.
  • Tension leg platforms have smaller platforms with taut lines running straight to the floor below. These are lighter but more vulnerable to earthquakes or tsunamis because they rely more on the mooring lines and anchors for stability.

Each platform must support the weight of the turbine and remain stable while the turbine operates. It can do this in part because the hollow platform, often made of large steel or concrete structures, provides buoyancy to support the turbine. Since some can be fully assembled in port and towed out for installation, they might be far cheaper than fixed-bottom structures, which requires specialty boats for installation on site.

Floating platforms can support wind turbines that can produce 10 megawatts or more of power – that’s similar in size to other offshore wind turbines and several times larger than the capacity of a typical onshore wind turbine you might see in a field.

Why do we need floating turbines?

Some of the strongest wind resources are away from shore in locations with hundreds of feet of water below, such as off the U.S. West Coast, the Great Lakes, the Mediterranean Sea, and the coast of Japan.

In May 2021, Interior Secretary Deb Haaland and California Gov. Gavin Newsom announced plans to open up parts of the West Coast, off central California’s Morro Bay and near the Oregon state line, for offshore wind power. The water there gets deep quickly, so any wind farm that is even a few miles from shore will require floating turbines. Newsom said the area could initially provide 4.6 gigawatts of clean energy, enough to power 1.6 million homes. That’s more than 100 times the total U.S. offshore wind power today.

Map showing offshore wind potential
Some of the strongest offshore wind power potential in the U.S. is in areas where the water is too deep for fixed turbines, including off the West Coast and offshore from Maine. NREL

Globally, several full-scale demonstration projects are already operating in Europe and Asia. The Hywind Scotland project became the first commercial-scale offshore floating wind farm in 2017, with five 6-megawatt turbines supported by spar buoys designed by the Norwegian energy company Equinor.

While floating offshore wind farms are becoming a commercial technology, there are still technical challenges that need to be solved. The platform motion may cause higher forces on the blades and tower, and more complicated and unsteady aerodynamics. Also, as water depths get very deep, the cost of the mooring lines, anchors, and electrical cabling may become very high, so cheaper but still reliable technologies will be needed.

Expect to see more offshore turbines supported by floating structures in the near future.

Matthew Lackner, Professor of Mechanical Engineering, University of Massachusetts Amherst

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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July 17, 2021 2:06 pm

These will only work if the earth was flat, otherwise they will tip over.

Charles Higley
Reply to  John Shewchuk
July 17, 2021 4:34 pm

Stay away from Guam. I hear it is going to tip over, according to one of our highly informed, but illiterate Congressmen.

Bryan A
Reply to  Charles Higley
July 17, 2021 4:59 pm

Since both Wind and solar are essentially FREE ELECTRICITY and are Far Cheaper than traditional fossil sources, California should use them to power desalination plants creating much needed water AND creating a drop in sea level from the water extraction.

Last edited 9 days ago by Bryan A
Reply to  Bryan A
July 17, 2021 6:37 pm

Free electricity is rubbish. So are coal and diamonds free if no royalties are charged. Government could charge royalties of parking a turbine installation in waters under their control. They could also put a tax on any electricity landed on shore. What ever way one produces electricity there is capital involved and a cost to maintain the capital assets in a working condition. Reliable, 24/7 available electricity from any wind turbine is still much more expensive than from nuclear and coal fired power stations. Further, wind turbines are ugly and use a large amount of space which could be put to better use.

Reply to  cementafriend
July 17, 2021 8:14 pm

So… aside from all that, you’re OK with them?

Geoffrey Williams
Reply to  Bryan A
July 17, 2021 6:38 pm

Just so siily . . .

Bryan A
Reply to  Geoffrey Williams
July 18, 2021 9:53 am

And so are intermittent unreliables as a primary power source

Last edited 8 days ago by Bryan A
Reply to  Bryan A
July 17, 2021 6:52 pm

If they are free, then why are our taxes going up to support the Green Deal, and why are people dying while experiencing this free energy …

Pat Frank
Reply to  Bryan A
July 17, 2021 7:38 pm

Wind and solar are essentially FREE ELECTRICITY…

The linearized cost of energy fallacy.

… and are Far Cheaper than traditional fossil sources,…

Unless you count the cost of tax subsidies and intermittency.

“California should use them to power desalination plants creating much needed water AND creating a drop in sea level from the water extraction.”

The living in unicorn-land fallacy. One mm of sea level = 350 km^3 of water.

The US uses 322 billion gallons of water per day. One km^3 of water = 264 billion gallons. 350 km^3 = 287 days water use of the entire US.

So CA desalinization alone is going to lower sea level? When all human water use eventually returns to the oceans anyway?

Reply to  Pat Frank
July 17, 2021 8:21 pm

Pat. There’s a 12-step program for the sarc-challenged.

Kindest regards,

P.S. Gave you an upvote. It was good of you to present the facts, even when someone was just having a laugh at the greenies’ expense.

Pat Frank
Reply to  H.R.
July 17, 2021 8:56 pm

H.R., thanks. Can’t help it. 🙂

Peter Barrett
Reply to  Bryan A
July 18, 2021 3:46 pm

If they position the desal plants high in mountains the purified water could generate hydro power on its descent to inhabited regions. The possibilities are endless.

Reply to  Charles Higley
July 17, 2021 6:50 pm

Too late — I spent 3 years there at the Joint Typhoon Warning Center — and it was very stable — unlike what Hank Johnson thinks …

John Hultquist
Reply to  Charles Higley
July 17, 2021 8:20 pm

 It is funny that said congress critter is from the State of Georgia where the Okefenokee Swamp is found. The “Land of Trembling Trees” does have floating islands. How would he know Guam doesn’t float?
Adm. Robert Willard, head of the U. S. Pacific fleet deserves an Oscar for his performance while listening to Hank.

Reply to  Charles Higley
July 18, 2021 5:02 pm

What do you mean One?

Mark D
Reply to  John Shewchuk
July 17, 2021 6:49 pm

IMO this is another example of just because you can do it doesn’t make it a good idea.

Tom Halla
July 17, 2021 2:07 pm

Someone is deliberately ignoring the effects on sea birds and whales.

Curious George
Reply to  Tom Halla
July 17, 2021 2:33 pm

These effects will not be quantifiable. There will be no nosey conservationists counting bird carcasses at the foot of the windmill. There will be a higher-than-usual concentration of sharks, just like reported elsewhere.

Charles Higley
Reply to  Curious George
July 17, 2021 4:38 pm

Wait, where has the shark density been found to increase? I am a marine biologist and had not heard of this?

Mark D
Reply to  Charles Higley
July 17, 2021 6:53 pm

Seams reasonable the electric currents generated could act upon ampullae and cause sharks to come for the nonexistent prey.

Peter Fraser
Reply to  Charles Higley
July 18, 2021 12:36 am

Working on New Zealand offshore gas pipelines it, was not uncommon to come across bronze whalers bimbling along the pipe but this could have been the slightly warmer temperature of the line.

Charles Higley
Reply to  Tom Halla
July 17, 2021 4:37 pm

Ah, wind turbines will be given a pass as they destroy species we have spent many decades to protect. Who needs seabirds and whales when totally useless power can be generated for EV vehicles that are effectively useless? Sounds like a plan.

Tom Halla
Reply to  Charles Higley
July 17, 2021 4:44 pm

Just like one is not to mention child and forced labor in the Congo mining cobalt. One must stay on message.

Mike McMillan
Reply to  Charles Higley
July 17, 2021 6:10 pm

Unlike seabirds, whales instinctively know to avoid the spinning blades.

Reply to  Mike McMillan
July 17, 2021 6:37 pm

It is the long wave frequency they put off that disrupts the whales.

Mike McMillan
Reply to  Tim
July 18, 2021 12:05 am

Thank you.

Tom Abbott
Reply to  Tim
July 18, 2021 6:54 am

Don’t forget the Dolphins.

Jim Whelan
Reply to  Mike McMillan
July 18, 2021 4:56 pm

Mostly by not jumping too high out of the water.

Reply to  Mike McMillan
July 18, 2021 8:01 pm

According the assumed whale protectors, ropes and lines running from the surface to the ground cause damage to and even kill whales.

July 17, 2021 2:14 pm

How about SF Bay so they can live with them.

Tom Abbott
Reply to  ResourceGuy
July 18, 2021 6:56 am

Good idea. Let the California Elites live in full view and hearing of their windmill decision.

Reply to  ResourceGuy
July 18, 2021 6:57 am

Better yet, the Carquinez Strait… use the “Mothball Fleet” ships as platforms for the wind turbines.

Shoki Kaneda
July 17, 2021 2:15 pm

Sounds like a great, low cost solution like the California high-speed train.

Charles Higley
Reply to  Shoki Kaneda
July 17, 2021 4:40 pm

Do not expect a high speed train to run on wind-generated power. It would be high speed until the wind died or gusted or the backup batteries failed or exploded, then it becomes a bookend for the train line, a place keeper for where the power failed.

Willem Post
Reply to  Charles Higley
July 17, 2021 6:40 pm

Oh, no!

The trains will run at variable speed on wind power, 24/7/365, unless there is too little wind.

In that event, we will call the Dem/Progs to congratulate them on another successful boondoggle, that enriched their friends and families, like the Biden/Pelosi, Inc. shenanigans of yore.

Reply to  Charles Higley
July 17, 2021 10:27 pm

A high speed train will still have significant inertia after the electricity fails unless perhaps there is some strong back emf involved.

Rud Istvan
July 17, 2021 2:27 pm

Just two problems, professor.

First, in 2016 (when I did the analysis for Judith at CE in post ‘True Cost Wind’) after correcting for several gross (likely deliberate) EIA errors, the LCOE of CCGT was about $57/MWh, and onshore wind was about $146/MWh. About 2.5x. Awful.

Second, in its 2/1/21 newest LCOE report EIA has offshore wind costing 3.7x onshore. Even if you engineer viable floating wind turbines (the axial bearing problem gets worse when wave action is added to rotor wobble), their cost is off the charts prohibitive compared to CCGT—about 9.5 times as expensive. Ridiculous. Just because something can be done does not mean it should be done.

Reply to  Rud Istvan
July 17, 2021 2:59 pm

“when wave action is added”……yeah, that wave action is really really problematic when your floating drilling platform has a 5000 foot drill string attached…

Rud Istvan
Reply to  Alan
July 17, 2021 3:22 pm

Alan, if the cables are tensioned, waves will snap them or pull the anchors. If they have some slack, waves will wobble the turbine superstructure. You may never have anchored a decent sized boat. I have, for many decades. You always leave anchor road slack to account for waves.

Reply to  Rud Istvan
July 17, 2021 4:11 pm

I suggest you speak to Dave Middleton regarding floating drilling platforms…..he’ll know all about them because of his work in the Gulf.
Most of the structure that provides buoyancy is below the surface of the water. The boats you anchor are floating on the surface.

Rud Istvan
Reply to  Alan
July 17, 2021 4:55 pm

The deepwater Gulf stuff isn’t anchored at all. It is continuously positioned by impellers. And those drilling platforms weigh a whole lot more so harder for waves to push around than a measly wind turbine, whose blades must be as light as possible—carbon fiber epoxy.
Don’t need to consult Dave Middleton on those basics, since all are readily internet available. BTW, do you ever use it to check before posting?

Reply to  Rud Istvan
July 17, 2021 6:51 pm

Thank you Mr. Istvan, for admitting that a properly designed platform will not be affected by “wave action.”
PS a 1.5 megawatt GE turbine weights in around 164 tons. You forget the tower weighs a lot. Have you anchored any 100+ ton boats lately?

Last edited 9 days ago by Alan
Reply to  Alan
July 17, 2021 7:22 pm

I see that your inability to understand what you are reading continues unabated.

Just because a little bit of wave action doesn’t matter to a drill string, is not proof that a little bit of wage action doesn’t matter to a spinning propeller.

Iain Reid
Reply to  Alan
July 17, 2021 11:45 pm


1.5 Megawatt, factor in availability at maybe 40%, why are they playing with such toys, that is a small generator for a lot of money.
Modern power station shave generators rated in hundreds of megawatts

Reply to  Alan
July 18, 2021 1:07 am

I once helped anchor a 33000 ton semi submersible drilling rig in the middle of the North Sea. It still moved with the waves. If it floats waves are going to move it.

Reply to  Notanacademic
July 18, 2021 2:50 am

Me too, lots of times.
A long swell coming from the west off California will cause problems with the turbine bearings as the top oscillates.

Reply to  Oldseadog
July 18, 2021 3:22 am

We weren’t allowed to use the cranes if wind was 40 knotts or more because the rig moved around to much. These things are tiny in comparison and Alan thinks the waves won’t affect them?

Reply to  Notanacademic
July 18, 2021 7:10 am

Alan thinks 

There’s your problem

Reply to  MarkW
July 18, 2021 12:08 pm


Reply to  Alan
July 18, 2021 5:03 am

Apparently 1.5 megawatt is small for oceans, but anyhow, lets
go with it.
PS a 1.5 megawatt GE turbine weights in around 164 tons. “
How much do wind turbines weigh? In the GE 1.5-megawatt model, the nacelle alone weighs more than 56 tons, 
the blade assembly weighs more than 36 tons, and the tower itself weighs about 71 tons — a total weight of 164 tons.”
It seems it would easier to put it in deeper water, but we go
with around 200 feet of water.
Have top 100 feet be 4 meters in diameter, and bottom 100 feet
go from 4 to 8 meters in diameter. Have 10 meter diameter flange
in which attached 6 screw anchor which can’t put out will 20 tons
and load them with 2 tons each, or pulled in total by 12 tons.
And thickness of steel is 1″ thick. If fill the 100 feet 4 meter diameter part with air, it float more the all the weight.
But before put the 164 tons of upper tower and wind mill on, what effect would say Cat 6 hurricane have on it without wind mill?
No, wait, put just 212-ft tower and put crows nest on top, how dangerous would be in the crows nest?
The tower 71 tons and 212 ft, and 4 meter diameter 100 ft part is about 75 tons steel. Seems wind would not have much effect, bigger issue is the waves.
How much wind speed can any wind mill survive?
” When wind speeds surpass a modern utility-scale turbine’s rated wind speed, the blades begin to feather, or point into the wind to reduce their surface area. In some instances, although not common, the blades can even be locked down to ride out severe gusts.
Despite this shut off, the yaw drive, located in the wind turbine’s nacelle, continuously points the rotor into the wind, even as weather patterns shift as they pass through.”
Although this was not a hurricane, it does demonstrate the shutdown process. The wind farm sustained wind speeds higher than 70 mph during the automatic shutdown and successfully powered back up to serve Block Island after the winds diminished.”
Apparently some doubt about over say 100 mph, What else:
The average survival speed of any range of turbine size can be as low as 100-130 mph, going up to speeds of 180 mph for larger machines. This programming is necessary for every wind turbine to maximize safety and efficiency. 
When Hurricane Irma was headed toward the coast of southern Florida in August, it had maximum wind speeds of 185 mph, according to the New York Times.”
So plan is to survive a Cat 5, but work the face the wind, and have low profile to this wind- and can be locked.

Reply to  gbaikie
July 18, 2021 11:28 am

The rated speed for a hurricane is down near the surface.
Those turbines are over 100 feet tall, with the blades reaching higher than that. As you go up in altitude, the windspeeds get greater. So the actual wind speed that is hitting the turbine is a lot higher that 185 mph.

Reply to  MarkW
July 18, 2021 1:35 pm

Well, since tax dollars paying for these things, they should drag one into path of strongest hurricane they can get and see how does, rather have bunch connected to grid and find this out when a hurricane hits.
What I am talking about does not need anchoring to sea floor to conduct the test- the anchoring is mostly to keep in a location and float for miles during hurricane and the towing crew could avoid most of hurricane.

Charles Higley
Reply to  Rud Istvan
July 17, 2021 4:51 pm

I just bought my second sailboat, had the first for 50 years, 26 foot, 2200 lb steel ballast keel, and 4500 lb displacement.

The new old (54 years) 35 foot sailboat (in better than excellent condition) has 5200 lb lead ballast of lead and it is 1.5 feet to the top of the lead under the cabin floor (i.e., much lower center of gravity), total displacement 12,500 lbs.

These are completely different systems, the former being a nice boat I lived on for years and took from Florida to Maine, but a bit responsive to waves and such. The later is more like a rock and responds little to average waves and such. However, the later also involves much larger forces when it does move and those have to be seriously taken into consideration. It moves more slowly but can do much more damage if not controlled.

Rud Istvan
Reply to  Charles Higley
July 17, 2021 6:01 pm

My big sailboat was a Hunter 35.5, with the winged keel. Loved that boat for many years and Lake Michigan adventures. Winged keel was great for max hull speed, but not so great when Lake Michigan got ugly. Which was too often.

Mark D
Reply to  Rud Istvan
July 17, 2021 7:11 pm

Charles and Rud I am envious. I started too late in life. Loved my 46′ pilothouse staysail cutter but my health (that and a Coast Guard rescue) caused my wife to force me to swallow the anchor.

Mark D
Reply to  Rud Istvan
July 17, 2021 6:59 pm

Rode. Nothing like pulling up 300′ of chain after the winch decide to take the day off. “Cruising”. Boat repair in exotic places.

Last edited 9 days ago by Mark D
Peter Fraser
Reply to  Rud Istvan
July 18, 2021 1:04 am

All these mooring methods are high wear, high maintenance which means greater costs. Usually very heavy studded link chains which are secured to driven piles on the seabed are used.The mooring systems need to be inspected every three years. The catenary of the chains is very important in maintaining stability and chain length needs be adjusted as they wear.

michael hart
Reply to  Peter Fraser
July 19, 2021 10:54 am

Yes. I am convinced my odds of a long life are better if I stay on the land as much as possible. The sea has a strong propensity to break all things, living and mechanical.

t port
Reply to  Rud Istvan
July 18, 2021 6:27 am

What about the gyroscopic effect of the spinning blades? Does that also complicate the engineering as the rig is moved by wave action?

Jim Whelan
Reply to  t port
July 18, 2021 9:14 pm

Additional bearing strain for sure!

Jim Whelan
Reply to  Rud Istvan
July 18, 2021 5:10 pm

This is more like anchoring a large sailing ship with full rigging. The whole point is to capture the wind energy and the cables must fight the effect of the wind on the blades more than just the waves. A lot of torque trying to tip it over too since the pressure is mostly at the top with almost none at the bottom.

Anchor slack is usually more important to account for tides than wave action.

While operating there will likely be a lot of pitch as well. The blades will not directly face the wind resulting in bearing issues. Any attempt to keep the blades vertical risk the tips encountering the support.

My conclusion: far from as simple as the article claims.

Reply to  Jim Whelan
July 18, 2021 6:54 pm

“This is more like anchoring a large sailing ship with full rigging.”

Not really.
it’s more like:

Deadhead. A floating Log, usually referes to logs the float vertically in the water, with only a portion of one end of the Log visible.

Jim Whelan
Reply to  gbaikie
July 18, 2021 9:13 pm

Except these things have these huge wind capture devices on the upper end! A Deadhead with a sail.

Reply to  Jim Whelan
July 18, 2021 9:56 pm

Sure, deadhead with a sail.
Or research platform FLIP with sail.

[FLIP doesn’t have sails, but it does have booms.
But one could imagine it has sails]

Jim Whelan
Reply to  gbaikie
July 18, 2021 10:35 pm

My point, which you seem to be missing entirely, is that the blades add a significant element of difficulty to stabilizing the structure which does not seem to be considered in the article.

Reply to  Jim Whelan
July 19, 2021 4:57 pm

Well I was referring 1.5 MW, they have 10 MW and they are making 15 MW ocean wind turbines:

It seems to me, they are making the largest wind turbines in the Ocean.
Which makes sense to me because it’s easier to make huge things to be on the Ocean as it’s easier to move huge stuff on ocean as compared moving on roads.

Reply to  Rud Istvan
July 18, 2021 8:08 pm

You always leave anchor road” rode “slack”.

Reply to  Alan
July 17, 2021 7:20 pm

Drill strings are flexible. Do you have any other nonsense comments that you wish to make?

BTW, the longer the drill string is, the less meaningful a little bit of wobble in the drilling platform becomes.

bill Johnston
Reply to  Rud Istvan
July 17, 2021 3:46 pm

You are obviously not a rich renewables investor. They like this stuff.

Charles Higley
Reply to  bill Johnston
July 17, 2021 4:52 pm

It’s the subsidies. Without them, it’s a nonstarter.

Dave Fair
Reply to  Charles Higley
July 17, 2021 6:02 pm

Just ask the Sage of Omaha.

Reply to  Rud Istvan
July 17, 2021 4:11 pm

California is planning a lot of things, all of them very expensive. But then again, California is also paying foreign nationals with federal stimulus money because it wouldn’t be fair to them if they don’t.

California also has introduced legislation to raise its top income tax rate to 16.8% and a new wealth tax of 1.5%. California also taxes capital gains at ordinary income rates. And lets not even talk about sales taxes which already approach 10% in most populated areas.

So money is no object to California politicians, where the top 1% already pay more than 50% of all taxes. They can gold plate the wind turbines too, to match California’s “Golden State” nickname.

Reply to  Doonman
July 17, 2021 8:48 pm


All those taxes – high taxes – and there are idiots suckers gluttons for financial punishment people who still stay in California?

I suppose the nice weather (most of the time) is worth the risk of the whole shebang sliding into the sea.

Full disclosure. I’m long on Arizona ocean front real estate.

Geoffrey Williams
Reply to  Rud Istvan
July 17, 2021 6:45 pm

I agree with your statement that just because something can be done then it should be done.
The cost required in terms of materials and energy to build these things must be enormous.
I wonder if these machines will ever recover the costs . .

Reply to  Geoffrey Williams
July 17, 2021 7:25 pm

Cost doesn’t matter, when you are spending other people’s money.

Reply to  Rud Istvan
July 17, 2021 7:33 pm


There isn’t anything in the article about how they plan to keep these things facing into the wind.

Whenever they pivot the generator and blades, the tower is going to want to turn in the other direction. When the tower turns, it’s going to try and wrap the guide wires around itself, keeping the guide wires fully taut.

Reply to  MarkW
July 18, 2021 7:12 am

Who would downvote a simple statement of fact? Unless it is someone to whom facts are inconvenient things.

Thomas Gasloli
July 17, 2021 2:30 pm

Wind turbines on land need subsidies to be profitable, near shore turbines need a larger subsidy, so now they want deep water turbines that will need an even larger subsidy. California logic

Carlo, Monte
Reply to  Thomas Gasloli
July 17, 2021 3:41 pm

“Dig Deep!” (into your wallet, that is)

Shanghai Dan
Reply to  Thomas Gasloli
July 17, 2021 3:47 pm

Hey, we lose money on each unit but we make it up in volume!

Or something like that… Seems to work for a lot of Silicon Valley money…

Dave Andrews
Reply to  Thomas Gasloli
July 19, 2021 6:51 am

I don’t know how much the subsidy was but the Hywind Equinor offshore wind farm shown at the start of the article cost 2 billion Norwegian Krone or about £1.64 billion.That’s five floating windmills at £328m each.

July 17, 2021 2:33 pm

Will be interesting to see which commercial technology overcomes its ‘technical challenges’ … floating wind farms or cold fusion?
Given that land-based wind farms are not even commercially viable without subsidies, I’m putting my money on cold fusion.

Rich Davis
Reply to  Harves
July 17, 2021 3:26 pm

You can just hand it over to me. I’ll hold it for you until the cold fusion breakthrough.

July 17, 2021 2:39 pm

I would think that one of the most critical factors for the viability of floating offshore wind farms would be the height & steepness of waves / depth of troughs in Force 9 gales.

Have any old master mariners been asked what to expect in a common typhoon?

Mark D
Reply to  Mr.
July 17, 2021 7:16 pm

I can tell you first hand what happens in confused seas when the “elephants” erupt under your boat LOL!

July 17, 2021 2:57 pm

Of course there are no problems regarding extending the power grid to the floating turbines.
The connection to the grid will be reliable too.

Tom Halla
Reply to  walt
July 17, 2021 4:48 pm

Just like the malign effect of too much wind power on theTexas grid last February. A good windstorm during a cold spell . . .

July 17, 2021 3:49 pm

Only crackpots and Democratic politicians would sink that kind of money into something that cannot deliver what it promises.

July 17, 2021 3:49 pm

ive scoured the internet to try to find the cost to build the mayflower wind farm off mass . there is lots of info about how cheap the power will be , I assume from big subsidies , but nothing about what it will cost to build . anybody know anything ? right now nearby block island offshore wind , the nations only offshore wind , is out of service due to problems with underwater transmission cables while providing the nation’s most expensive electricity when it is operating .

H. D. Hoese
July 17, 2021 3:52 pm

I have a picture of a moderate surf down the beach off Point Reyes, seems to show a large flat presumable rip current, went to the beach and took a perpendicular picture of same, apparently persistent feature. Will the turbines have a rip current or other wave/ current warning? Someone is also retrying getting energy from waves, all these look good from a desk, I suppose, or maybe they just looked up the meaning of pacific. I’m not an engineer, but knew quite a few over the years, they used to be smart and do field work.

July 17, 2021 3:58 pm

Progress from the green to bluewater blight through diversity and inclusion. One step forward, two steps backward.

Reply to  n.n
July 17, 2021 10:33 pm

n.n.: One step forward, two steps backward.”

So eventually the Progressives will get there?

Wait… something isn’t adding up.

Jeff L
July 17, 2021 3:59 pm

All 3 types of platforms mentioned in this article are technology already established and used in deep water oil & gas production, so the technology isn’t the issue per se other than applying it to a wind power application.

The economics is another question all together though.

Reply to  Jeff L
July 17, 2021 7:28 pm

Nobody said they can’t be built. The question is and has always been, at what cost.
The other point is that even a tiny amount of swaying that is caused by wave/wind action will drastically increase the wear and tear on the bearings.

Pat from kerbob
Reply to  MarkW
July 17, 2021 9:43 pm

Yes, a fan 50m across above the ocean is so completely different a beast than a spaghetti string of steel under the sea it’s laughable to compare them as Alan did above.

Non-mechanical people

Jeff L
Reply to  MarkW
July 18, 2021 6:27 am

Actually, if you read the comments , there are a lot of people here that questioned if they can be built.

Reply to  Jeff L
July 18, 2021 7:13 am

How long they will last once built is a different question from can they be built at all.

David Dibbell
July 17, 2021 4:03 pm

The platform motion may cause higher forces on the blades and tower…” Yes. In aviation, there are large gyroscopic forces on a spinning propeller in response to yaw and pitch changes. Same thing.

P Wells
Reply to  David Dibbell
July 17, 2021 4:16 pm

Have you considered the substantial difference in size between an aviation blade and a power-generating windmill blade?

Reply to  P Wells
July 18, 2021 2:41 am


And your point is?

P Wells
Reply to  Disputin
July 18, 2021 2:14 pm

And my point is that you obviously do not understand the problem.

David Dibbell
Reply to  P Wells
July 18, 2021 4:40 pm

Sure, the much larger size would increase the mass and moment of inertia so as to increase the effect, and the much slower rotation would tend to diminish it. What am I missing? Sincere question.

Tony Taylor
July 17, 2021 4:14 pm

This reminds me of that generator which pulled weights up and down. Great looking and fun experiment, especially if it came in kit-form for kids to build at home, but not exactly the solution to our energy needs.

Charles Higley
July 17, 2021 4:17 pm

I believe Germany built a seabed wind farm years ago and included it in their green energy total but I have never heard that they ever actually connected the wind farm to the shore. Things last a long time when they are not used, and looks good on the tally.

Charles Higley
July 17, 2021 4:26 pm

A challenge will be how the wind turbines, which are sloshing about on their moorings, will also deal with the variable directions of wind that often comes in gusts. This should be lots of fun, watching how they discover that they cannot they control the turbines without breaking subsystems, such as moorings.

They also have not solved the problem of blade edge erosion which has plagued the sea turbines in the UK and EU and which drastically impairs turbine efficiency. It is a serious and real problem that the idiots pushing for this prefer to ignore.

Also, no mention of the ocean environment being very hard on every component of such systems, from the blades to the turbine to the structure to the mooring system and, most vulnerable of all, the electrical network connecting them to the grip. This will indeed be super expensive and fun to watch. Go get the popcorn.

Reply to  Charles Higley
July 17, 2021 6:28 pm

Charles: Great questions! You beat me to the first one.
Just how do fixed-base wind turbines keep pointed into the wind?
Now do that on a moving/twisting base. Can’t be good on the moorings, or the bearings.

As an aside, back in the 1970’s my father-in-law had a windmill (for the cattle water trough)
and, since back then I was the most spry person, I got to climb up and oil the thing. It also had a vane that kept the blades pointed into the wind. I also was elected to adjust the vane to so as to disable the windmill if needed.

Zig Zag Wanderer
Reply to  Bill Zipperer
July 17, 2021 8:39 pm

I thought they needed grease, not oil? They do here in Oz where they are quite common.

Reply to  Zig Zag Wanderer
July 17, 2021 9:54 pm

My recollection is a pan that I filled to a certain level with motor oil. There may have been some places to grease but I don’t recall him ever suggesting I do so. It worked for several decades before finally rusting-out. He replaced it with an electric pump.

Joel O'Bryan
July 17, 2021 4:27 pm


  • On shore wind power electricity: expensive and unreliable
  • Off shore, fixed wind power electricity: very expensive, and reduced trubine and blade operational lifespan
  • Off-shore, floating wind power electricity: ungodly expensive, short serviceable lifespan.

What could go wrong?

Frank Hansen
July 17, 2021 4:46 pm

So the floating platforms will be moored to the ocean floor. That will not work in the waters off the pacific coast of Japan. Just 50 km out from the coast the depth goes up to 11 km, the deepest trench on Earth.

July 17, 2021 4:47 pm

Offshore floating nuke plants anyone ?….the tech already exists, just we call them Subs and Carriers….

Doug Huffman
Reply to  DMacKenzie
July 17, 2021 5:22 pm

While we had a ‘surplus’ of marine NPP that might have been reasonable. Now we have barely sufficient numbers and the deficit will shortly become critical.

Tom Abbott
Reply to  DMacKenzie
July 18, 2021 9:08 am

The Russians are building nuclear powerplants on ships. They will dock in your town and power your town with their nuclear reactor powerplant. At least, that’s their plan. Newsom ought to order a couple of Russian nuke ships if California needs extra power, and I’ll bet they would be cheaper than building floating windmills.

And no maintenance costs. The Russians would take care of that.

Last edited 9 days ago by Tom Abbott
Steve Case
July 17, 2021 5:37 pm

Years ago the liberals were crabbing about the oil rigs off of the Santa Barbara coast and how ugly they are and the spoiled the ocean view. The local paper published a cropped telephoto of them from way back on the beach to make them look gigantic from the shore. I suppose the reaction from our friends on the left will be a bit different regarding these planned monstrosities.

Rich T.
July 17, 2021 5:54 pm

Some ideas on offshore wind power. Never mind biden’s plan to waste trillions of dollars with a unworkable green scheme. And the cable problems can kill any power transmission. Just ask Tasmania, UK. And here is another Willis on offshore wind power. Cheapest NOT!!!!!!. And california will run out of power when they most need it.

Reply to  Rich T.
July 17, 2021 7:35 pm

If they run out of power, they will just review the voter registration roles, and cut off power for Republicans first.

Gary Pearse
July 17, 2021 6:09 pm

The very ones who call thinking people (aka sceptics) climate den*iers are apparently in deep de*nile about the fact there are several thousand coal power plants under construction or soon off the drawing board in Asia and Africa to raise their citizens out of poverty.

The bottom line re policy options is: whether consensus climate is correct or not is totally irrelevant . The developing world is now responsible for 65% of CO2 emmissions and accelerating. Nothing will stop it. The West can do their 150 trillion economic and social self immolation to no avail. We are locked in to 600ppm before 2100.

Among high profile climate doomsday promoters, this reality on the ground cannot be a secret. This and a fair probability of continuance of the 6yr global cooling trend must be causing considerable anxiety among them. Gavin Newsome, not so much.

Tom Abbott
Reply to  Gary Pearse
July 18, 2021 9:16 am

“The developing world is now responsible for 65% of CO2 emmissions and accelerating. Nothing will stop it. The West can do their 150 trillion economic and social self immolation to no avail. We are locked in to 600ppm before 2100.”

Absolutely correct. Nothing will stop it. Get used to it, alarmists.

The good news is, all indications are that 600ppm will not be a problem for life on planet Earth.

July 17, 2021 7:15 pm

Yes, there are a few “demonstration” projects currently “operational”.
However, have the been “operational” long enough to produce any useful data?

Pat Frank
July 17, 2021 7:21 pm

Expect to see more offshore turbines supported by floating structures in the near future.

All for nothing.

David Dibbell
Reply to  Pat Frank
July 18, 2021 5:43 am

It’s truly sad to see this slow-moving disaster of wasted effort and attention called “climate action.” And it’s all based on unsound attribution to CO2 emissions of what cannot be ruled out as natural. It’s the right thing to do, to keep on exposing the misconceptions.

Tom Abbott
Reply to  David Dibbell
July 18, 2021 9:25 am

“It’s truly sad to see this slow-moving disaster of wasted effort and attention called “climate action.”

Isn’t that the truth! We are watching a slow-motion trainwreck to which most of our leaders appear to be oblivious. CO2 is not a reason to turn the world upside down.

The unfortunate outcome of these actions is clear to some people. “I told you so”, will be said, but that may be too late to prevent the crash.

Idiocracy combined with political powergrabbing. That’s what is powering the CO2 “crisis”.

July 17, 2021 7:46 pm

“…there are still technical challenges….” The devil is in the details.

Pat from kerbob
Reply to  markl
July 17, 2021 9:49 pm

I’m betting on warp core tech

old engineer
July 17, 2021 10:01 pm

It turns out this is not just some professors dream. The link below shows the last of five floating wind turbines being installed off Aberdeen, Scotland, a couple weeks ago.

It will interesting to see how these units perform.

Reply to  old engineer
July 18, 2021 2:47 am

“It will interesting to see how these units perform.”

At a guess, badly?

Nigel in California
July 17, 2021 10:11 pm

So, we are not allowed to drill for oil, but we can tie down thousands of cables.


July 18, 2021 1:16 am
willem post
July 18, 2021 3:30 am

Future Build-outs of Offshore Wind Turbine Systems in New England

– MA, RI, and CT are planning to have 8460, 880, and 4160 MW, respectively, a total of 13,500 MW of offshore wind by 2035, much greater than the above 1600 MW.
– If the same simulation were made for 13,500 MW of wind turbines, the up/down spikes would be about 10,000 MW
– The existing CCGT plants would be inadequate to counteract them, i.e., output curtailments would be required.
– The 2035 date has a ring of urgency to it, but likely would be unattainable in the real world. See page 13 of NE-pool URL
It would take at least 20 years to build out 13,500 MW wind turbines off the coast of New England, plus large-scale solar systems to reduce the NE grid CO2/kWh by about 30%
With that much wind and solar, the NE grid would become very unstable. The NE grid would need:
1) Curtailments of wind output, kWh, on windy days
2) Curtailments of solar output bulges on sunny days
2) Major connections to the Canadian grid
3) Grid-scale batteries, with a capacity of 3 to 4 TWh; turnkey capital cost about $1.5 to $2 TRILLION, at $500/kWh, delivered as AC

NOTE: Nearby countries import German overflow electricity, when it is windy and sunny, at low grid prices (because of a German surplus), and export to Germany, when it is not windy and not sunny, at high grid prices (because of a German shortage). 
The Netherlands is one of the major beneficiaries.
German households get to “enjoy” the highest electric rates in Europe, about 2.5 times as high as the US
Denmark, another wind country, is second!

Maine Offshore Wind Turbine Systems are Dead
The ocean waters near Maine are deep. Almost all offshore wind turbines would need to be floating units, anchored at the seafloor with at least 3 long cables.
The 700-ft tall wind turbines would need to be located at least 25 miles from any inhabited islands, to reduce the visuals, especially with strobe lights, 24/7/365
The wind turbines would be far from major electricity demand centers, such as Montreal and Boston.
Transmission systems would be required to connect the wind turbines to demand centers
All that would make the cost of electricity produced by these wind turbines more expensive than those south of MVI.
Maine is Desperate to Stay in the Wind Turbine Business

Maine wind/solar bureaucrats likely are in active discussions with stakeholders to add 751 MW of onshore wind turbines.
Maine wind/solar bureaucrats are not in active discussions with stakeholders to add offshore wind turbines, as shown by the interconnection proposals on page 13 of URL

European Companies Building Offshore Wind Systems

Almost the entire physical supply of US East Coast offshore wind systems would be by European companies, because they have the required expertise and the domestic onshore and seagoing facilities, due to building at least 25,014 MW (end 2020) of offshore turbine systems, during the past 35 years.
Those companies would hire qualified US labor, as needed. 
Those companies would build US facilities, as needed. 
Those companies would not be interested in training a potential competitor.

The EU vs the US

 The US, with a low-cost, self-sufficient, energy sector would attract European, Korean, Japanese, etc., energy-intensive, heavy-industry and industrial product production to the US.

Europe is interested to make sure the US has a high-cost electrical sector, with lots of high-priced wind and solar and batteries, to handicap the US, and to enhance its competitiveness vs the US. The UN is helping out by urging the US to expensively reduce its CO2 by 50% by 2030, which is not possible. See URL.

– Europe desperately needs more low-cost gas from Russia to remain competitive on world markets
– Europe has to build out wind and solar to limit energy imports from unstable countries; the US does not need to.

very old white guy
July 18, 2021 4:13 am

What could possibly go wrong and how much will the subsidies be? Has anyone figured out how to build them without mining, smelting and fossil fuels yet?

July 18, 2021 4:26 am

So let’s see, the most sustained winds are in Northern California well away from most population centers. How much line loss will there be conveying the electricity to Portland, San Francisco, Seattle, Los Angeles? And how about the power lines that will need to be placed in the pristine northern forests of California? We’ve seen how well PGE keeps them clear of vegetation.

Last edited 9 days ago by buckeyebob
July 18, 2021 4:58 am

California is planning floating wind farms offshore to boost its power supply – here’s how they (are supposed) work

July 18, 2021 5:00 am

Do the floating platforms account for locked rotor forces as is common for large turbines or motors/generators on land?

July 18, 2021 7:09 am

And then there is the issue of maintenance cost. Land-based wind turbines are difficult enough, but maintenance in an unforgiving marine environment is probably going to add an order of magnitude. Routine maintenance will be rather expensive, but non-routine stuff (repairs) gets very, very expensive, very, very quickly.

July 18, 2021 7:16 am

Floating wind turbines? God help us. Well, it is now official. What, if any affect at all co2 has on the greenhouse has been surpassed by something just discovered called the madhouse gas and alarmists are the largest emitters.


July 18, 2021 7:43 am

Ref to the very first picture:
“Equinor and partner Masdar invested NOK 2 billion to realise Hywind Scotland”
Construction cost: £264m

Someone badly needs to go to jail.


John Bell
July 18, 2021 9:06 am

The very FACT that we can build such things is ALONE PROOF that we do NOT need them.

July 18, 2021 10:47 am

And the next tsunami will presumably tip them all over, pull out all the anchor cables and destroy the power cables. Still, they will probably blame it all on climate change!

Reply to  IanE
July 18, 2021 11:36 am

In the deeper oceans, tsunami waves are rarely more than a few feet high.

July 18, 2021 11:10 am

When I think of California doing something that is a difficult and expensive engineering project, I think back to their high speed rail they were building. One of the few things you can guarantee is that it will be an order of magnitude more expensive and require much more time to accomplish and will provide half of the energy they expected.
The entire project will be an exercise in very expensive stupidity and a waste to the taxpayers.

Last edited 8 days ago by Philip
Coeur de Lion
July 18, 2021 11:34 am

As a sometime oceangoing seafarer, I would not insure such a device against catastrophe.

Wade Hampton
July 18, 2021 1:43 pm

Floating wind turbines. Sounds like a fairly simple engineering challenge. Let’s put Ibrahm X. Kendi and Robin DiAngelo on the problem.

July 18, 2021 3:23 pm

How these are supposed be defensible from a potential enemy attack from the sea?

July 18, 2021 7:52 pm

Right in the path of migrating whales the left has been so vociferously blaming everyone else for any/all damage the whales suffer.
Add in all of those wind platform steel cables into the migration path of the whales either proves eco-alarmist claims wrong or increases whale damage many times.

July 19, 2021 7:55 am


Bill Everett
Reply to  Wharfplank
July 19, 2021 8:22 am

How about putting the present California government on barges and pushing them out to sea.

Bruce Cobb
July 19, 2021 1:59 pm

If the wind turbine floats, does that mean it’s a witch? I can never remember.

July 19, 2021 4:11 pm

$5 says if they build this they’ll underbuild the stays and the suckers will float together because of drag and have bumfights.

July 23, 2021 6:24 am

I read no discussion of the length, cost, and placement of transmission lines required to move the electricity from offshore to onshore. This does not include some type of transformers or other methods of regulating the power from offshore to onshore.
Submarine transmission cable costs are somewhere between $115,000 to $300,000 per mile.
Before such a project is completed in California, I suspect the costs will multiply by 10X or more.

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