David Wojick, Ph.D
CFACT President Craig Rucker has blown the whistle on Federal plans to put hundreds of floating wind generators off the Oregon coast. Floating wind is the latest green energy fantasy, taking its place along with hydrogen, EVs, battery storage, and net zero.
The idea is that where the water is too deep for conventional offshore wind generators, we will simply put these huge towers and turbines on floats. Pretty much all of the West Coast fits this bill, as does most of Maine.
Responding to a Federal request for comments on a big floating wind proposal for Oregon, Rucker explains clearly that the technology needed to do this does not exist and may never exist in an economically feasible form. The federal agency is the Bureau of Ocean Energy Management (BOEM). The plan is to designate hundreds of thousands of ocean acres as Wind Energy Areas and then start auctioning them off to floating wind developers.
His succinct comments are here: http://www.cfact.org/wp-content/uploads/2023/11/Comments-concerning-BOEMs-Draft-Wind-Energy-Areas.pdf
I want to dive into the technology a bit to show what a boondoggle floating wind really is.
First, let me say that, sure, we can put huge turbine towers on floats. Our fighter jets take off from and land on floats, right, floats called aircraft carriers. But they are really big, hence expensive. The same is true for floating wind, albeit at a somewhat smaller scale.
Look at it this way. Suppose you took a sailboat and put a 600′ tall mast on it. At the top, you put an 800-ton turbine with three 500′ long wind-catching blades. How big would that boat have to be not to blow over when hit by severe wind and waves?
The answer is very big indeed, in fact, huge. Now compare this huge float with the simple monopile that conventional offshore generators sit on. The monopile is a simple steel tube, maybe 30′ in diameter and a few hundred feet long, driven solidly into the ocean floor.
Compared to the huge float, the monopile is small and cheap. But simple monopile base offshore wind facilities are already tremendously expensive. Floating wind is projected to cost much more, from 2.5 to 3 times more, in fact.
In addition to the huge float holding up the turbine tower, there have to be a bunch of monster mooring chains anchored firmly to the ocean floor in all directions to keep the float from rocking too much in heavy seas or from capsizing. Then, too, the power lines taking off the electricity have to somehow get from these bobbing floats to the distant shore.
The highly specialized fabrication facilities and work boats required to make and install all this stuff in deep water do not exist. Given that over 50 vastly different floating wind designs have been proposed, we do not even know what to build.
I say projected because no utility-scale floating wind facility exists in the world today. BOEM is talking about quickly building thousands of Mega Watt (MW) of floating wind. Five leases pegged at 3,600 MW have already been sold off California. But as Rucker points out, the biggest facility in the world today is an experimental 88 MW and that just fired up a few months ago.
Those five California leases are, in effect, experimental. The developers are each going to try to produce an economically viable floating wind facility. As things stand, the odds are very long against them. I can hardly wait to see the Construction and Operations Plans, which are the first required step in the long road toward project approval.
But the ultimate crunch point is selling the juice via a Power Purchase Agreement (PPA). If costs run three times regular offshore wind, which is already extremely expensive, then the required PPAs might simply be unobtainable.
However, California just passed a law allowing the State to directly buy offshore wind energy. Perhaps the plan is for the State to buy horrendously expensive electricity, sell it to the utilities at the much lower going wholesale rate, then let the taxpayers eat the losses. It is, after all, Crazy California.
Mind you, this silly game is being played around the world. Several countries have launched similarly speculative large-scale floating wind projects, and many more are talking about it. Of course, they are also talking about mass-scale hydrogen, EVs, and net zero. It is all part of the same green nonsense.
As for the American floating wind fantasy, stay tuned to CFACT as this engineering comedy unfolds.
Hilarious, indeed
Fatuous.
Flatuous
This is a particularly stupid idea even for renewable energy. Among the many, many, many problems: a facility that floats for 20 years is going to have even higher maintenance costs than a fixed one. And I suspect the creation of these floats would be even more expensive.
I attended the VERGE conference a couple weeks ago. One of the people I talked to there was working on windmills on drones. Very small windmills on very small drones, that is. Literally tethered drones that would take off when the wind is blowing and land when it is not. Powered by electricity. Funded by at least 2 US military groups and SBIR and whatnot. But I simply cannot see how even a supposed 10kW (AFAIK) per drone at peak wind, given intermittency, is going to make up for the cost of having hundreds to thousands of such drones sitting around although the military use case is probably reduction of diesel for generator costs. Hundreds to thousands of such drones also would require an enormous area – difficult to reconcile this with “security”. Civilian use…ugh.
But that’s how the renewable cookies crumble.
Nothing a proof of concept wouldn’t solve.
We can find out easily enough. The Hibeki floating turbine system is anchored off the Japanese coast. It should be easy to find out if this proof of concept prototype will sink or swim.
The first ones didn’t do so good.
https://mainichi.jp/english/articles/20210305/p2a/00m/0na/034000c
Good, good. Oh sorry, such a shame, such a disappointment and after they spent $580 million on it as well. Never mind.
Hibiki is a premium whisky by Suntory. My kids gave me a bottle for my birthday a couple of years ago. It was very good.
I think we are getting close to Peak Wind.
I’m not so sure – have the democratic presidential debates started yet??
Democrat, not democratic.
Do ya really think they’ll let Joe trip over his own tongue at a debate? His handlers would go NutZ trying to control his potential verbal diarrhea let alone stop him from wandering off stage
But he will have to debate the Republican challenger. Of course, they’ll try to set those debates as close to the day of election or even the day, after as they can, so that most of the voting will already be over with. then all that will be left to be taking the time to figure out how many votes they need to stuff into the ballot boxes during the counting process.
According to Ballotpedia…
Peak Insanity.
You know you’ve reached the nadir of society when a blithering idiot is elected to the highest seat in the nation…Idiocracy
I’ve read biographies of many of America’s founding fathers. By comparison to them, most politicians today are blithering idiots. Just finished reading for the 2nd time, “Washington” by Ron Chernow. It was said about Washington, “first in peace, first in war, and first in the hearts of his countrymen”.
We’ll see.
Probably not, particularly if cost estimates are re-examined and end up being from 20.5 to 30 times more expensive than monopiles.
We’ve seen.
Math and science does not lie and economics will not be denied.
What it takes to make a vessel stable has been known for centuries, as what happens when you attempt to rock an object that is spinning.
Since land-based Wind hasn’t worked, what makes you think floating wind turbines will be any better?
They do have one advantage: the foundation flexes, rather than being rigidly piled into the seafloor. That allows some stress to be relieved. But the overall system cost is horrendous.
And decommissoning should be much less. Just cut them loose and let them sink.
Why all the neg votes for “We’ll see”?
Because we’ll only see if it is a giant success.
The turbine bearings would not last very long. They seem not to know about the gyroscopic forces that will tear these things to pieces.
How close do the blades come to the surface? When I was in the Navy, sometime around 1975, some green water knocked off a sat dish on the island. 75? 100? feet above the water. Hard to imagine blades surviving much of that. If the wind blows it to, say, 45°, the tips will be that much closer. IANAE but it doesn’t seem unlikely.
I think there’s a good amount of offshore experience to call on for such issues. The HYWIND design is in water depths up to 120m in some of the stormiest North Sea weather. The turbine hubs are ~133m above mean sea surface and have 154 rotor diameter, or 77m blades, which therefore are at least 56m above the surface. Equinor comment:
Most offshore wind floater designs are similar to the ones applied for the oil and gas platforms. Floating turbines are moored to the seabed with multiple mooring lines and anchors, in much the same way as a floating oil platform. Floating wind turbine motion controllers stabilises the turbine through regulating the turbine blades, optimising power production and reducing stress on tower, substructure and moorings.Most offshore wind floater designs are similar to the ones applied for the oil and gas platforms. Floating turbines are moored to the seabed with multiple mooring lines and anchors, in much the same way as a floating oil platform. Floating wind turbine motion controllers stabilises the turbine through regulating the turbine blades, optimising power production and reducing stress on tower, substructure and moorings.
Apologies for the doubled quotation. Hywind has managed 5 years of operation so far and has consistenly been the highest capacity factor wind farm in the UK offshore. However, its extra cost far outweighs the better capacity factor.
Not responsive to SR’s posr. He asked about what happen to floating windmill when it tips.
You replied by stating that we have plenty of experience with fixed windmills.
No, I quoted Equinor who point out we have plenty of experience with floating offshore platforms. In 4,000ft of water in Walker Ridge, GoM for instance, as well as in the North Sea. Hutton TLP was built almost 40 years ago.
Here’s a paper that fed directly into the design of Hywind. The maximum angles of tilt are only a few degrees, and certainly nowhere near 45 degrees.
https://www.researchgate.net/publication/286277866_Modeling_and_Parameter_Analysis_of_the_OC3-Hywind_Floating_Wind_Turbine_with_a_Tuned_Mass_Damper_in_Nacelle
There will be added stress on the machine line and thrust bearings because of movement of the float – side to side and up and down in addition to the usual stress from changes in wind speed and direction which will further shorten their already limited lifetime. Yes there are ways to solve this problem, but you do not want to know the cost. Add to that that salt eats the …. out of everything, and you have an all round bad idea.
I don’t think those problems can be solved for floating wind turbines. They are not solved for stationary onshore wind, which is why Siemens Gamesa took a $3 billion hit recently. Premature axial bearing failure.
As a maritime engineer who worked for decades on many kinds of ships, I can assure you that there are bearing systems which can withstand the stresses that a floating wind turbine will experience. They are expensive and very heavy but essential to make ships work so we use them. Will they be within the weight and space limits of a wind turbine generator perched atop a 500 foot tower on a floating barge? I don’t know for sure but I am confident it can be done but at a much greater expense than the way it is now done, perhaps to great an expense for the value produced.
Denis,
I am sorry to say you are wrong. The forces from big thunderstorms and hurricanes never blow from one direction or at a constant speed. With the passage of fronts the wind can veer 180 degrees in seconds and under thunderstorm downbursts all propeller blades are being driven down together and if feathered face even greater forces. No bearings can sustain those forces for a long period.
Aircraft propellers have to be taken off after 2000 hours for very detailed inspections yet wind turbines sit up there without ever having that requirement and would not stay in balance for very long from the various types of damage that can occur from hail, lightning and flying debris. You cannot design against vertical shear on wind turbines from downbursts under thunderstorms. Under these downbursts jet aircraft are incapable of outclimbing those forces in landing or taking off under thunderstorms. There were 26 such accidents in the US in the early history of jet transport so to suggest it is possible that wind turbines and their bearings can be designed against this sort of weather is fanciful.
But aren’t they already too great an expense for the value received?
Just a bit of engineering …
Actually design allows some of the stresses to be reduced, just as with a tree bending in the wind. See
https://www.researchgate.net/publication/286277866_Modeling_and_Parameter_Analysis_of_the_OC3-Hywind_Floating_Wind_Turbine_with_a_Tuned_Mass_Damper_in_Nacelle
As always, why don’t these proposals self fund a proof of concept sub-scale demonstrator? We here know why.
I posted a mention a few days ago about the prototype floating wind turbine barge that’s in positiin off the japanese coast. The Hibeki barge has already been built – we should be able to look at that as an example of whether this will work and what it will cost. My guess is iffy and monumentally big.
National energy policies are increasingly anti-science and more specifically anti-engineering.
Proof of concept.
Sub-scale demonstrator.
Single integrated deployment.
Then a decision to full scale deploy.
Yes. In the grand scheme of things it doesn’t take a lot of money to prove these ideas worthless. Some experimentation is quite affordable.
However it is the embarkment upon full scale deployment without proper assessment that causes the real economic damage.
Unfortunately this seems to be the norm these days for various ‘planet-saving’ ruses.
They are given serious time and money by politicians when there are plenty of science and engineering people who could tell them it is a waste of time and money.
Trying to keep everybody cold in a 2.56 million-year ice age with 4.6 million people dying every year from heart attacks and strokes caused by the cold making people’s blood vessels constrict to preserve heat raising blood pressure. About 500,000 people die each year from heat.
Offshore floating wind is really an idea that has been pushed because Norway has a large surplus from its oil and gas earnings, so the greens decided to make Equinor invest in green projects, including carbon capture, which has been abandoned as too costly even for Norwegian tastes, and offshore floating wind (Tampen supplies its power to oil platforms – power that could have been and was provided at much lower cost simply by running gas turbines at the platfrom). When the UK greens offered to provide massive subsidies to burnish their credentials the HYWIND project was born.
My money is on the oceans.
They’ll snap those mooring chains and these worse-than-useless things will all end up ass over tip in no time.
The next big tsunami will wash them all ashore next to the carcasses of the whales killed surveying for, building and operating them.
Love the rubber duckies bases, the perfect expression of the child-like thinking of those who think any amount of useful energy will ever be produced by this stupidity.
In Britain, we have one floater – HYWIND
It gets paid a subsidy of about £170/MWh, on top of the money it earns from selling electricity, which puts total revenue upto over £250/MWh.
https://en.wikipedia.org/wiki/Hywind_Scotland
World’s first commercial wind farm using floating wind turbines, in the North Sea off the Scottish coast
Hywind Scotland is the world’s first commercial wind farm using floating wind turbines, situated 29 kilometres off Peterhead, Scotland. The farm has five 6 MW Siemens direct-drive turbines on Hywind floating monopiles, with a total capacity of 30 MW. It is operated by Hywind Limited, a joint venture of Equinor and Masdar.
30 MW design, or actual? How much electricity has this site been producing on average. What has been its peak output. How many days has its output been at or near zero? How much did it cost?
Just looked it up. Nameplate is 30MW (6*5MW each). Capacity factor to date 54%. So producing about 16MWh.
The book cost was £264.7m, or £8.94m/MW. There is already a £36m decommissioning reserve as well. Peak output has been the full 30MW (probably plus a few kW). You can see monthly output in GWh here:
https://www.ref.org.uk/generators/view.php?rid=R00001FTSC&tab=mw
There is a distinct seasonality.
Maintanence on wind turbines on land is no easy job- climbing up the ladder inside. I don’t think they have elevators. Maintenance on floating wind turbines will be much more difficult, I’d think- and much more expensive. Right?
The ones at Kincardine were towed to port for repair. They were out of action for ~a year each time.
Hywind Tampen in Norway just opened as well – 11 turbines rather than Hywind Scotland’s 5. It looks like they’re secured to the seabed though – are they floated into position and then sunk onto a prebuilt seafloor base or piling?
They are tension anchored, a technology pioneered at the Hutton North Sea oilfield. The platform floats and would float higher absent the tension anchors. The same technique is used in some of the deepwater GOM developments of oil and gas, such as Mars, Auger and Olympus.
The Hibiki turbine is tethered in place by 9 pre-installed anchors. It has two blades that sit horizontally atop the pylon
The value of the subsidy has grown. It’s 3.5ROCs per MWh, currently worth ~£65/ROC, or £227.50/MWh.
There is a second floater in the UK – Kincardine:
https://www.offshorewind.biz/2021/10/19/worlds-largest-floating-offshore-wind-farm-fully-operational/
which is also on 3.5ROCs per MWh subsidy. The accounts reveal it has been going through difficulties. First generation was in September, 2018, but it took 3 years before all turbines were commissioned and commercial operations were declared. Altogether it’s approximately 50MW of nominal capacity – 5 Vestas 9.5MW 164m span and 1 Vestas 2MW 80m span. In the balance of 2021 it produced 45,818MWh – an average of 17.2MW, or just 34.4% capacity factor, which is hardly impressive for a £400m, £8m/MW asset. On 30th December 2021 one of the turbines failed, resulting in repairs lasting until November 2022. In July 2022 another turbine went u/s, and repairs were anticipated to take a year. Over 2022, generation was 131,380MWh, giving an average of just 15MW or 30% on the nominal capacity, but if we allow for the turbine downtime the operating part achieved about 42% – no better than fixed offshore turbines.
Revenue totalled £48.3m in 2022, an average of £367.67/MWh, of which £201.07/MWh came from ROCs (which have subsequently had a big indexation boost – the indexation is added every April, along with the other factors that determine ROC base cashout prices that get inflated by a built-in shortfall of generation based ROCs).
It’s really not a poster boy for an economic offshore wind business. The turbine problems, affecting Vestas 9.5MW turbines, show it is not just Siemens with difficulties with these larger machines. The HYWIND turbines from Siemens are a bit smaller at 6MW.
Vestas has been having problems with it’s turbines longer than Siemens have, or rather, longer than Siemens will admit to.
Nontheless in April 2023 Vestas secured a 238MW order to provide 25 turbines to Hibiki Wind Energy for offshore wind.
That should be the right size for what is planned:
Offshore equipment, especially electrical power equipment is super expensive to survive conditions where only birds survive by flying above the waves….only a Pollyanna would believe that free wind and free real estate is sufficient to cover the costs.
How will these huge massive monsters fare when they’re bobbing up and down 30-50 feet in stormy weather? My bet is that at a minimum they will tear their moorings apart and wreck their mast to nacelle connections if the masts don’t collapse first. There are real limits to how big you can make things without running into strength to weight issues.
PS: Love the illustration.
and what if there is a tsunami?
Tsunamis in deep water are typically just a small swell. It’s not until the reach shallows close to shore that they pile up into massive waves. But in deep water there’s a possibility of rogue waves large enough to capsize large ships. That might present a spot of trouble for a floating wind farm.
Never underestimate the power of Magical Thinking.
Unfortunately, magical thinking backed up by the force of law can be a dangerous and even deadly combination.
Well, I propose that they lift all restrictions on offshore oil drilling and install the usual production platforms. The benefits are myriad, including a reliable energy source for many decades, followed by a fully paid for structure to which any wind toys could be affixed, if desired. Presumably, even bigoilbob would approve!
Here’s an interesting comparison: Chevron’s Petronius platform cost about $500m, the same as the Kincardine floating wind farm (£400m). It was to tap 100m bbl of recoverable reserves, about 160TWh of energy. The wind farm was expected to produce 200GWh a year, but has so far fallen well short. If it succeeded in producing 200GWh/a over a 25 year life, it would total 5TWh of production. That’s a factor of 32 times the cost at the level of primary energy. Of course, there will be larger losses in converting oil and gas to useful output that there will be for the electricity from the wind farm, but it will be fully dispatchable energy, available when required. The comparison is stark.
“Mind you, this silly game is being played around the world.”
The poker ‘tell’ here is that the best options for windpower have come up gravely inadequate. They went for land based wind first. NIMBY aspects, health concerns, the sterilization of 100s of thousands of km² of land, eyesore factor, chopping down national parks wiping out millions of birds, bats and insects and the overriding problem of intermittentcy of wind availability (IOWA).
They moved offshore to solve much of the land-based problems. Birds casualties would go unnoticed, but whales went crazy, beached themselves and also were forced into dangerous shipping lanes, and, of course
They were more expensive to build and maintain, a harsher environment shortened service life and ….. IOWA remained!
So, they went for the much more expensive floating of the failed system in deep waters to save the whales. But they took IOWA, the overriding problem, with them. Who is really in denial?¿
“How big would that boat have to be not to blow over when hit by
severeextremely small wind and waves?”Fixed it. 🙂
It wold be so top heavy that it would be like trying to stand a pencil up on a table on it’s point. I presume the “float” would have to be roped to the bottom or have an extremely heavy anchor going down hundreds of feet. Just guessing since I have no clue- not an engineer.
The floating Hibiki turbine in Japan began operating in May 2019 and is tethered in place by 9 pre-installed anchors.
1 in 2019? So they haven’t decided to power their nation with more? Japan is a high energy nation so it’ll need hundreds of thousands more. Instead, I think they’re beginning to restart their nuclear plants?
Statoil first built a floating offshore turbine in 2009. It was extremely costly for its size. They’ve cut the cost by 70% since, but still that works out as more than 3 times the cost of fixed offshore per MW of capacity.
“Rucker explains clearly that the technology needed to do this does not exist and may never exist in an economically feasible form”
But… but… no price is too great to save the Earth and to provide virtue signalling for the Oregonians! /sarc
“It is, after all, Crazy California.”
Crazifornia. Almost as bad as Wokeachusetts.
I can help them. Build a couple nuclear power plants. There fixed it for you.
Not living in the USA, my knowledge of the geography and geology is therefore somewhat limited.
What happens if there are even small earthquakes?
Can the epicentre for such quakes be in the ocean?
Is the west coast vulnerable to typhoons?
The southern west coast near Mexico gets typhoons.
SInce they are floating, the chances of them being damaged by earthquakes is small.
I was thinking more of offshore quakes affecting sea conditions, not necessarily a full blown tsunami.
Since they are floating, does this mean they aren’t witches? Asking for a friend.
Nice one, Skippy.
Only if off Salem, Mass.
“…the technology needed to do this does not exist and may never exist in an economically feasible form.“
That’s not a bug. That’s a feature. Needs a bigger subsidy from printed dollars.
you have a point but some of your numbers don’t make sense …
you claim the monopile is a 30 inch tube several hundred feet long ??? you really believe a 30 inch pipe can be pounded into the seabed for HUNDREDS of feet …
seriously, not on this planet …
and even if such a thing existed (nobody can fabricate/ship and install a 30 inch 200-400 foot pipe) … and it wouldn’t support a huge wind turbine ….
somehow you imagine the “floaters” are like a conventional buoy with a single floatation chamber … you couldn’t be more mistaken … they are usually a tripod type of arrangement that don’t require “chains” ??? (really, chains?) … they use cables …
the offshore oil industry has been using large floating platforms for decades …
I agree that the costs may be higher than the current seabed based mounting system but that as yet to play out in the real world …
Look here:
30ft, not 30 in.
YOu really should look at how things are currently being done, before declaring them impossible.
First off, they don’t drive the entire pipe in at the same time. There are several techniques, the one I”m most familiar with is to drive a portion of the pipe into the sea bed. Then weld the next section of pipe onto the first, then drive that portion into the sea bed.
Lather, rinse, repeat until the pipe has reached the length desired.
I’m sure there are other methods as well.
Just because you limited imagination is incapable of finding a solution is not evidence that everyone else is equally limited.
While it is true that the oil industry has been using floating platforms, while true, isnot relevant to this problem as the requirements are completely different.
Oil industry platforms only need to be high enough to keep the drilling platform itself out of the surf.
Wind mills have to be high enough to keep the blades, when they are at their lowest, out of the surf, this means that the entire platform has to be hundreds of feet taller than drilling platforms.
THis means that the wind will have much much more effect on windmills than it does oil platforms.
“floating wind” – ‘nough said…..
And of course, no proof that these floating windmills will produce enough energy to offset the CO2 emissions of their production, operation, maintenance, and intermittancy.
“First, let me say that, sure, we can put huge turbine towers on floats. Our fighter jets take off from and land on floats, right, floats called aircraft carriers. But they are really big, hence expensive.”
Those “floats’ also happen to be nuclear powered. If BOEM is willing to go with nuclear powered floats for the wind turbines this could work. Something like the diesel powered solar scam in Spain a few years back. It would still be crazy expensive, but clearly those guys don’t care about cost or we would not be having this discussion in the first place.
No just stop. It is a nutty idea period. Just because we might be able to build it does not mean it is fit for purpose. What next power lines to space? Beamed energy from orbital space solar farms. Extreme ideas are a dime a dozen. Tell them to spend their own personal funds first. Leave me out.
It is not as though wind generators are good for grid supply. They are not an equivalent to conventional generators but few will know or appreciate that fact.
Politicians seem to think that wind (and solar) can replace conventional generation, sometime, sooner or later, they will find out their error.
Those final words will come to describe far more than just wind power generation. Carbon sequestration, slow high=speed trains that after 15 years around 80 percent has achieved environmental approval; battery powered EVs as general transportation.
At first I thought the writer was describing the “war on terror.” Afghanistan is such a better place now.
Let’s put water turbines in the Gulf Stream and generate lots of power while concurrently cooling Europe, maybe even creating a European Mini Ice Age. Cool, a twofer.
Equinor, a Norwegian company, just put in operation 11 Highwind, floating offshore wind turbines, each 8 MW, for a total of 88 MW, in the North Sea.
They will provide electricity to 2 Norwegian oil rigs.
The existing diesel generators on the rigs will counteract the up/down output of the wind turbines, and provide almost all the electricity during low-wind periods.
The capital cost of the whole set-up is known to Equinor and the Owners of the oil rigs, but that info is carefully hidden from the public.
The production cost likely will be greater than 46 c/kWh, without subsidies, more than
23 c/kWh, with subsidies
Rich Norway can afford to dabble in such expensive follies, but impoverished Maine would buckle some more under such a heavy burden
If such units were used off the California coast, a high voltage cable would be hanging from each unit, until it reaches bottom, say about 1000 feet.
That hanging cable would need some type of support system
Then the cable would run horizontal to shore
Tampen is in up to 300m/1,000ft of water in the Norweguan Trench. At least they will have good data on weather and sea conditions from the oil and gas platforms. It will only supply an average of around a third of the power requirement, and at least they already have the gas turbines needed for backup.
“Look at it this way. Suppose you took a sailboat and put a 600′ tall mast on it. At the top, you put an 800-ton turbine with three 500′ long wind-catching blades. How big would that boat have to be not to blow over when hit by severe wind and waves?”
I think the dimensions are a bit exaggerated, since the largest wind turbine in the world has 425 foot long blades; but, hey, it’s not that far off.
As an engineer, I would do several things to wind turbine design to make it economically feasible, or at least more so. The first is putting the generator on the ground, and connecting it to the rotor via gearboxes and vertical shafts. That greatly alleviates both the high center of mass problem, and the ghastly maintenance procedures. I would also build the rotors using aluminum wing technology, which might be heavier (though not necessarily as much as you might think), but would be both less expensive than composites, and both repairable and recyclable, which composite blades are not. Fora floating wind turbine, I’d extend the tower shaft well below the waterline, albeit with a smaller diameter, and fill it with concrete, all to minimize the overturning moment. Mounting the whole thing on a semi-submersible would be the cheapest route for off-shore basing. Would it be worthwhile economically? Nope, no way ever. But t wouldn’t be as monumentally, stupidly uneconomical.