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Scotland Builds Power Farms of the Future Under the Sea
HughPickens.com writes "The Pentland Firth is a raw, stormy sound between the Scottish mainland and the Orkney Islands, known for some of the world's fastest flowing marine waters. Daily tides here reach 11 miles per hour, and can go as high as 18 – a breakneck current that's the reason people are describing Scotland as the Saudi Arabia of tidal power. Now Megan Garber reports in The Atlantic that a new tidal power plant, to be installed off the Scottish coast aims to make the Scotland a world leader for turning sea flow into electricity. Underwater windmills, the BBC notes, have the benefit of invisibility—a common objection to wind turbines being how unsightly they are to human eyes. Undersea turbines also benefit from the fact that tides are predictable in ways that winds are not: You know how much power you're generating, basically, on any given day. The tidal currents are also completely carbon-free and since sea water is 832 times denser than air, a 5 knot ocean current has more kinetic energy than a 350 km/h wind.
MeyGen will face a challenge in that work: The turbines are incredibly difficult to install. The Pentland Firth is a harsh environment to begin with; complicating matters is the fact that the turbines can be installed only at the deepest of ocean depths so as not to disrupt the paths of ships on the surface. They also need to be installed in bays or headlands, where tidal flows are at their most intense. It is an unbelievably harsh environment in which to build anything, let alone manage a vast fleet of tidal machines beneath the waves. If each Hammerfest machine delivers its advertised 1MW of power, then you need 1,000 of them to hope to match the output of a typical gas or coal-fired power station. "The real aim," says Keith Anderson, "is to establish the predictability which you get with tidal power, and to feed that into the energy mix which includes the less predictable sources like wind or wave. The whole point of this device is to test that it can produce power, and we believe it can, and to show it's robust and can be maintained."
MeyGen will face a challenge in that work: The turbines are incredibly difficult to install. The Pentland Firth is a harsh environment to begin with; complicating matters is the fact that the turbines can be installed only at the deepest of ocean depths so as not to disrupt the paths of ships on the surface. They also need to be installed in bays or headlands, where tidal flows are at their most intense. It is an unbelievably harsh environment in which to build anything, let alone manage a vast fleet of tidal machines beneath the waves. If each Hammerfest machine delivers its advertised 1MW of power, then you need 1,000 of them to hope to match the output of a typical gas or coal-fired power station. "The real aim," says Keith Anderson, "is to establish the predictability which you get with tidal power, and to feed that into the energy mix which includes the less predictable sources like wind or wave. The whole point of this device is to test that it can produce power, and we believe it can, and to show it's robust and can be maintained."
These turbines will kill all the fishies!
“He’s not deformed, he’s just drunk!”
Any underwater installation will face the same challenges as Tidal power, that is what to do about the biologicals. The ocean is teaming with life and it will literally grow on anything. What do you do when the entire underwater "windmill" is covered in barnacles? Every underwater generation scheme is toasted by the life problem. None of them are tolerant of all the sea life that will grow on and around the facility.
My grandpa always said that Scotsmen and water just don't mix. But then again, maybe he just meant TRUE Scotsmen.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
What is going to be the Energy Return On Energy Invested?
How expensive to install and maintain, as sea water is much harsher than having a wind turbine in atmosphere?
What is the expected lifetime of each generation unit?
Uh, Linux geek since 1999.
that's very easy. dump chemicals around the the whole thing as needed
A typical (500 megawatt) coal plant burns 1.4 million tons of coal each year. As of 2012, there are 572 operational coal plants in the U.S. with an average capacity of 547 megawatts.
http://www.ucsusa.org/clean_energy/coalvswind/c01.html#.VFe77y0wJIo
I don't know where the poster got their numbers from, but an average coal plant is around 500 megawatts not 1000. This would imply that you only need 500 of the hammerfest machines to equal a powerplant. They should probably be more careful in the future to use accurate data.
The tidal currents are also completely carbon-free
This myth needs to end. There is no such thing as a "Carbon free" energy source. Some are worse than others obviously. But very large, very heavy materials will need to be used to construct those turbines. Mines will get dug, parts will get shipped, maintenance will need to occur.
This doesn't have Tidal on it but you can bet it will fall somewhere between wind and solar.
http://www.scientificamerican....
Solar is the real eye opener and should serve as a lesson on blindly trusting hype and "What seems obvious." Solar panels are terrible for the environment, yet most people don't have a clue. Keep in mind, this chart does not include waste generated by actually collecting the power. That's why oil doesn't look so horrible. Nor does it take into account the environmental impact of hydroelectric damns. If you factor all that in, Nuclear is the least damaging to the environment but people are afraid of it so...
Ryan Industries have to start somewhere.
And that's why ocean going super-tankers where never possible.(sarc'). Doesn't stop the Thames Barrier and Dams/hydro power across the world does it.
How about: Clean them off.
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that's very easy. dump chemicals around the the whole thing as needed
He he, I know you're kidding... but that would be remarkably stupid thing to do in a high current area :)
Does this apply to places with strong tidal currents? I imagine it must be difficult to attach to a surface when you're being pulled by a strong current.
Ezekiel 23:20
Kill the fishies AND accelerate the moon so it will escape Earth's gravitational pull sooner than if we didn't try to harvest tidal power!
He could film it and use that to promote the project with the proceeds from the box office take
Go big or go home, as they say
You point to that figure and say that solar panels are terrible for the environment. Yes, apparently solar panels need more silver (and other metals) than other generation techniques, however, that doesn't mean that an ABSOLUTELY LARGE amount of silver is going to have to be provided.
Most power generation techniques don't need silver barely at all, so "relative to the current mix",yes, solar is going to need lots. That DOES NOT necessarily mean that supplying that amount of silver is going to cause widespread environmental degradation in the same way that coal DOES.
Also, solar power, once in place, doesn't require megatonnes of fuel like coal, oil, and gas do. (In that order, I guess.)
That figure doesn't DIRECTLY give insight into what energy mix is best for the environment, you can't have any hope of that unless you also compare fuel inputs per kwh generated as well, and other factors.
On the other hand, a stationary object in a strong current is an ideal place to sit there and catch food, so it's likely that sea life has evolved to take hold in such place.
The Bay of Fundy has the most powerful tides in the world. "The estimated potential of the Fundy region alone is upwards of 60,000 megawatts of energy, of which up to 2,500 megawatts may be safely extracted."
Nova Scotia had a trail running in Nov. 2009 with OpenHydro and they ended up having to remove their turbine when, "20 days later, all 12 turbine rotor blades were destroyed by tidal flows that were two and a half times stronger than for what the turbine was designed."
http://www.cbc.ca/news/canada/...
With such large amounts of energy why oh why are they pissing about with such tiny turbines? Modern wind turbines are 6MW+, some hydro power turbines are over 700MW each. Are they trying to destroy the financial viability of the project with unimaginative small scale thinking?
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re: "since sea water is 832 times denser than air, a 5 knot ocean current has more kinetic energy than a 350 km/h wind"
Kinetic energy is an integration of the linear mv dv so equals 1/2mv^2 (whereas momentum is the simple product mv.)
So let's set the mass of a volume of wind at 1 and the mass of the same volume of sea water at 832 units.
The kinetic energy of the wind @ 350km/h = 1/2 * 1 * 350^2 = 61,250 units
The kinetic energy of the water @ 5 knots = 1/2 * 832 * (5 * 1.852)^2 = 35,671 units (1 knot = 1.852 km/hr)
-- Insert witty one-liner here. --
If each Hammerfest machine delivers its advertised 1MW of power, then you need 1,000 of them to hope to match the output of a typical gas or coal-fired power station.
No, that's not "typical" at all. The largest coal-fired plants are 1-2GW; currently I believe there is no gas-fired plant anywhere in the world that is 1GW. So it would be more accurate to claim 200-500, while 1,000 is pure exaggeration.
The ocean is teaming with life and it will literally grow on anything. What do you do when the entire underwater "windmill" is covered in barnacles? Every underwater generation scheme is toasted by the life problem.
Cover every bit of metal with an insulating coating, then print, deposit, or laminate gold or platinum electrodes on the surfaces. Connect 'odd' electrodes in one branch of a circuit, 'even' electrodes in another, than apply an alternating voltage between them. The seawater completes the circuit. Unless a life form lands on the metal - then IT completes the circuit. I suspect most life forms will not like a continuous alternating current passing through them, and will 'move to greener pastures". Overall generating efficiency will be reduced, but probably not as much as it would be by barnacles, etc.
I'm not a marine biologist and I don't know if this would work - just tossing the idea out there.
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
They are experimenting with different coatings that reduce the amount of biological fouling. It's true that this problem is not solved yet, but it's worth developing the technology to overcome it because of the potentially massive gains possible.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Hard to build? Just build it somewhere else, tie some cement blocks to it, and heave it overboard! See, this is why I should be running everything.
This posting is provided 'AS IS' without warranty of any kind, implied or otherwise.
Underwater windmills, the BBC notes, have the benefit of invisibility—a common objection to wind turbines being how unsightly they are to human eyes.
Beauty in the eye of the beholder I guess but I've always found wind turbines to be beautiful. I could seriously watch them for hours.
Why try to poke holes in something that could result in renewable energy? Aren't there more problems to be found in oil spills, fracking, etc?
Stray electrical current... Metal parts... Salt water... What could go wrong?
http://en.wikipedia.org/wiki/G...
Oh, yeah...
Isn't Hammerfest a Scandinavian Folk Metal band. I swear I saw them in 2013 with Amon Amarth and Korpiklaani.
None of them can see the clouds; The polished wings don't care.
Simple: coat everything in paint with Transuranic waste additives!
The costs of such anti biological technology has sunk every under water power generation scheme. The floating tidal generators were fouled by kelp and ocean debris. The ones that took in water with the waves got clogged. And the lifetime on these systems wasn't even 6 months before they were fouled.
Ships are coated in horribly toxic materials and even so they have to be scraped near constantly at sea and most are pulled into dry dock every 10 years for a full high pressure high temperature cleaning. How do you clean these underwater generators? Do you send out drivers or haul them back to the surface and clean them? Both are wickedly expensive. I'm skeptical they will ever find the technology to basically prevent all life and prevent fouling by all the life floating around.
Well, damn! And here I thought going to 11 was really something.
You can pick a shallower water area for its higher tidal flow speed, but that increases stresses and chance for damage.
But there are deep water currents that are consistent at 5-6 knots which avoid almost all marine life in some places down 5-6000 feet deep. A few are in close to shorelines.
5 minutes of googling reveals: Saudi Arabia produces about 1.5 million m3 of oil, or about 60 million GJ of energy, per day. That's about 700 GW of continuous power. So to equal Saudi Arabia, these guys need to install 700,000 1MW turbines and run them continuously.
Not even sea life can ignore the laws of physics, though. ;-) It's been my understanding that barnacles need some time to attach properly, and in some places, I simply don't see it very likely that they'd have a chance.
Ezekiel 23:20
Sacrificial Anodes
because some people would probably rather not have a good idea ruined for a generation by a fiasco caused by shoddy implementation.
build it, but don't overstate, and take into consideration that it's a highly corrosive environment... and stuff in the ocean grows on everything... literally everything...
the fucking whales have barnacles growing on them... come on.
The ocean is teaming with life....
GO TEAM LIFE!
Sorry, couldn't resist...
Dark Reflection
So how do you clean them? Do you send divers down several hundred feet to hand scrape a moving blade? Do you haul them to the surface? Do you haul them to dry dock like they do ships every 10 years?
Ships constantly scrape while at sea and are typically brought into dry dock every 10 years for a thorough cleaning with high pressure / high temperature cleaning. This isn't a ship, it's a stationary bit of metal underwater in some of the coldest water on the planet. It's not going to be spinning fast enough to puree living mater like a ships propeller and they get fouled and have to be cleaned by hand all the time.
Everything in water ends up covered in living matter. This isn't a problem for stationary non-moving/non-mechanical objects. It is a serious problem for anything mechanical that for example needs to spin freely. Every tidal or current generating scheme requires moving parts under water and that's a problem for anything that isn't operating at puree speed.
Just do it when the tide changes. No current at slack tide.
There are two types of people in the world: Those who crave closure
While I'm certainly all for alternative forms of energy (which I consider anything not driven by fossil fuels.) this seems like a really piss poor idea and I'll tell you why: ITS SEAWATER, one of the most corrosive environments on this earth, and you wanna build things down there and expect it to keep going for a while? No. The maintenance alone is probably going to offset any perceived energy generation. There is no way this set up will generate enough power to pay for its maintenance over 50 years, if it even still works in 50 years. Bad idea.
Spend the money and time on LFTR nuclear reactors and quite pussy-footing around with stupid ideas.
But not sharks. Be like sharks.
There are two types of people in the world: Those who crave closure
<idea crazy="true">How about a sealed generator? Use a sealed bladder which gets compressed and rotated internally due to an internal instability? Think about sititng on top of a giant air mattress and trying to push all the air out by yourself. What happens? The bubble gets pushed around. Surely that sort of motion can be used for generating energy.</idea>
If it's enormous and heavy, it won't have to spin fast to crush anything that tries to wedge itself in somewhere, and then grind it into a fine paste.
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So how do you clean them? Do you send divers down several hundred feet to hand scrape a moving blade?
Isn't that what robots are for?
If that's too hard there are things that could be done with heat, current, toxins, anchors/winches, enclosing the moving parts inside a closed environment (propeller in the current sounds suboptimal) - when your machines don't have to move around the world, some limitations go away.
I'm no professional diver, but even just wreck diving in strong surges is quite a challenge - I can't imagine trying to get any work done. Human divers are probably a last resort.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
I don't see the problem here. Just put a straw downstream from the turbines and you have instant cioppino.
Do you send out drivers or haul them back to the surface and clean them? Both are wickedly expensive
They have to be tethered to something anyway (fixed power cable) - why not allow them to anchor/de-anchor so they can be pulled up to a cleaning ship? Why would that add a tremendous cost to each unit? No need for a winch on each unit - that can be on the ship. The one moving part would be some sort of attachment mechanism - the motor for that can even be on the umbilical from the ship. I'm assuming these things will be "smart" and can phone home with some sort of report about its need to be cleaned.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
"There is no such thing as a "Carbon free" energy source."
You're a dunce. There are plenty of carbon-free energy sources. It's the harvesting that is the problem.
Since the idea of both tidal and wave energy has been promoted since OPEC price disruptions of the 1970s (see Severn Barrage) but has never been successfully implemented (due to economic costs, largely managing brine and mollusks), either A) they have figured out a simple solution, or 2) they came up with a more novel solution, more interesting than the article suggests, or C) this is /.
Gently reply
Robots.
Hundreds of barnacle-scrapping robots per unit.
Sounds like a business opportunity to me.
Awww crap, somebody else beat me to it.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Uh, about that, the Rance tidal plant in France has operated for 40 years with nothing but sacrificial anode protection and it looks pretty good to me (see page 22).
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they've been testing underwater turbines for over 10 years in scotland so i guess they must have some solution regarding the corrosion and barnacles plus these are all still experimental and with all experiments, there will be failures along the way. all things that have moving parts require maintenance even the fossil fuel power stations but i would expect to see a lot less maintenance for these turbines
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
i doubt there'd be anything on a moving blade but they could just send down divers or submersibles to scrap anything off
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
No worries. It wont get built as the English wont pay for it as they havent forgotten the ungrateful bastards wanted Independence a few weeks ago
a common objection to wind turbines being how unsightly they are to human eyes.
The only people I remember complaining were the rich folks who live along the coast. As far as I'm concerned they can just STFU.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
It seems that a large scale project is viable, with a conservative large insurance company investing in a tidal power scheme:
UK Renewables May Be Turning The Tide
Large scheme, scalable to GW's of power, cheaper than off-shore wind, able to provide electricity on-demand, something that solar and wind aren't so good at.
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they must have some solution regarding the corrosion and barnacles
Coat them in dolphin pelts.
Sir! The undersea power farm--it's covered in eels!
When someone says, "Any fool can see
Neat.
540,000,000 kWh/year is an interesting way to express power though. Especially when it means that a power plant with 240 MW installed capacity is producing 62 MW average power.
This makes sense if 240 MW is the peak power generation, and 62 MW is average, given the cyclic nature of power generation, but still...
What if they made all the water-facing parts out of copper?
Or detach moving part, put a new in place and fish the old one up for cleaning/maintenance.
The French seem to of sorted it, see post #48303643 I've heard that the paint on boats and marine infrastructure is now polluting the oceans so I'm against paint that isn't biodegradable.
Personally I'm not keen on this system of dumping turbines into a bay, tidal lagoon and tidal barrier systems would surely reap far more power.
For example: UK Renewables May Be Turning The Tide
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Depending on depth barnacles and such might not be an issue. The ocean is actually more of a desert than an oasis so far as life goes.
I would propose whole units that could be towed up to the surface and placed in a barge for cleaning. It would probably be best to have a replacement unit already prepared and just swap them.
One of the things I'm curious about is whether or not sediment buildup could be a problem. The generate power from the tide the water must be slowed down. When the flow slows more sediment will settle out. Over time I wonder if the generating units will dune themselves in.
that's very easy. dump chemicals around the the whole thing as needed
Maybe we could use all the oil we're saving?
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
In the US we have these things which do pretty much that. I'm sure similar vessels exist in other areas. And these are tiny little things compared with what the oil industry uses to move rigs around and maintain them.
Remember the blowout preventer on the Deepwater Horizon mess? It was over 50 feet tall and was placed on the bottom of the ocean at a depth of 1600 meters. The technology is there, it's a matter of whether it is economically feasible to utilize it.
Faster! Faster! Faster would be better!
However the real problem would be how to maintain these things inexpensively while being submerged in deep saltwater with lots of moving parts. Good luck with that.
There has been an "experimental" barrage tidal hydro station operating for like 40 years in NS. There is a reason why there are only 3 operating in the world (Russia and France I think have the other two).
A) Saltwater sucks
B) Like normal hydro there are only so many suitable places for them
The energy isn't really the problem. The problem is trying to maintain something with lots of moving parts that is submerged in corrosive saltwater inexpensively. The short answer is you can't.
Hell even if it was freshwater, underwater maintenance would be terrible. Even lifting these suckers out for repair every so often would be trouble, never mind doing it where the currents and tides are strongest!
won't work, barnacles grown on whales... it's like their primary habitat or some shit :)
:) if they're like sharks, if you flip them upside down they crash. :)
...but this is just a greenie's wet dream.
> a 5 knot ocean current has more kinetic energy than a 350 km/h wind
But a 3.4 gromp wind is still much stronger than a 3,400 blerbster ocean current. So what?
If you can build them reasonably cheaply and out of non-toxic materials, maybe it's more economical to simply let the sea reclaim them, assuming the operational period pays for itself. We're essentially talking about underwater windmills and generators attached to big blocks of concrete. These things would only require a lot of high-tech if you're trying to make them last a really long time.
Can a single windmill pay for itself in 5 years? Would they last 10 unmaintained? If the answers to both questions are yes, maybe that's the way to go.
Irony: Agile development has too much intertia to be abandoned now.
Even if your turbine blades could be run at a speed that discouraged attachment, all the time, they would still foul eventually. However you cannot run the turbines all the time. Tidal power systems have to account for the fact that the tides cycle twice a day. There is a finite time in between when the water movement is zero or near enough.
Brand new and with some fancy coatings your turbine system will resist fouling. Eventually the metal pits and corrodes. Some algae or barnacles or mussels or coral attaches. As the surface roughens up it becomes quite hospitable for additional colonization. Many of the marine creatures secret glue or build protective armour and most of that stuff is like concrete, both in texture and strength.
Beyond that is the issue of the blade cowl and the turbine attachment points. All these are stationary and will foul. So even if you develop some kind of magical "no fouling" turbine blades then the mounting structures of the turbine will foul. The buildup of marine life eventually impinges upon the blade system and destroys the blades. Which is part of why all shipping has to be cleaned periodically.
Welcome to the internet, a giant interconnected machine that does nothing but spew hate and vitriol.
It's even more important to remember that some energy costs are already paid. For instance, if you float downstream on a river, the environment "paid the cost" of your transport. Less so if you use a one-time raft, but still. If you use a flowing stream to turn a water wheel, and from there do some work with it, again, the majority of the continuing costs are "paid" by the evap/precip freeze/melt cycles. When the "cost" of building a mill or a raft is just some stuff lying around and the sweat off your back, these energy supplies look very good indeed. Free? No. Hugely attractive to me? You bet.
I've fallen off your lawn, and I can't get up.
A pilot project (the joint effort of the Snohomish County PUD and the University of Washington) to extract power from tidal flows in Admiralty Inlet has been scrapped... at least partly due to the increasing cost of permits, licenses and newly mandated "studies" which the various government agencies were requiring. We are strangling ourselves.
This is not an easy thing to do. Perhaps one of the most difficult parts of this kind of project is anchoring the turbine to the sea bottom.
Whereever the flows are great enough to justify installation of a turbine, all the mud, sand, pebbles and small rocks have been long swept away. One of the folks on the UW project asked me to imagine an infinite field of bowling balls...
That is quite a unique and novel idea. And it just might be crazy enough to work.
Of the top of my head, I would be worried about the surface of the bubble to remain flexible in such tempeture and all the crap in the water. It also must be quite strong to withstand the pressure/pucture issues. Also the motion would be quite chaotic, so it may not be easy to make it do useful work.
It would be polite to mention that the link is to a largish PDF file.
What do I do? Curse the idiot designer who didn't go to high school and didn't specify anti-fouling paint.
WTF is it with you guys? As soon as something that can be linked in some way to green politics we get people who pretend their IQ has dropped by one hundred and roll out utterly cretinous reasons when the thing that could be seen as green will not work?
How about shedding the politically inspired stupidity (lot of it about this week) and discuss it as you would a space probe. Either that or keep up the silly games so that I can point at you and laugh, using you as an prize example of why coders shouldn't call themselves engineers.
Slack tide.
Tides go in and out, so yes, there's a peak when you can get maximum flow through the turbines and there's points where you don't get any flow at all. That one doesn't have an enormous reservoir to be able to maintain maximum flow for very long either.
Depends on the size of the turbines and the head pressure of the dam. Some tidal races move very quickly which would be equivalent to having a dam quite some distance above the turbines.
Check your units. If you are talking about coal go up from kW to MW. As an example to get some perspective, a power station I worked at had a backup generator to run the coal conveyers in case of a cold start and that was a single jet engine running as a gas turbine - a tiny one of it's type cable of producing 20MW. The steam turbines running from the coal fired boilers were 650MW each and there's now six units at that power station.
1 MW of solar requires 7.4 acres (http://www.entergy-arkansas.com/content/news/docs/AR_Nuclear_One_Land_Use.pdf)
1 MW will provide enough power for about 1,000 homes. Not bad!
1 MW = 3.412 MMBtu of energy. At 50% efficiency, that takes over 6 MMBtus of fuel to produce every hour. At $4/MMBtu (cheap natural gas) the tide is providing 4 x 6 x 8,760 = $210K of free fuel.
I don't know, it sound rather melodic a name to me, perhaps I'm just not saying it the right way.
The 240 MW is the rated power, so indeed the peak power generation capacity. Dividing 62 by 240 gives a production factor slightly above 0.25, which is like the performance of wind turbines stemming from the end of the last century. This has improved. I suspect that this will also be the case for tidal plants, considering this one is at least 40 years old.
It was my impression that it was ship hulls that got barnacle encrusted not ship propellers.
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
Yeah of course. The turbines are designed to be anchored to the ocean floor. If you turn them around they aren't going to anchored anymore so they will go with the flow and crash into the first available object they can find.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
Thank you, that was indeed very informative.
Stray electrical current... Metal parts... Salt water... What could go wrong? http://en.wikipedia.org/wiki/G... Oh, yeah...
As per the Wikipedia article you linked to, ensuring the metals that are in contact with or close proximity to each other have the same or similar anodic indices will largely address that problem. (That's why copper plumbing pipes are secured to joists by copper clamps; if they wer steel the pipes might eventually develop holes at the contact points).
I proposed either gold or platinum electrodes because they are the metals most resistant to corrosion. And I proposed Alternating Current because the periodic reversal negates any stripping / deposition effects of current flow. That's why electroplating, (and hydrolysis), use Direct Currrent - AC simply won't work for those purposes.
(In fact, some vaporizers available at the drug store don't have heating elements per se - just two strips of metal connected to the mains voltage and immersed in the water. They won't even work with distilled water, as it doesn't conduct electricity).
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
you realize that sharks like. literally have a software crash if you turn them upside down right? they go catatonic.
It's only 7MB and I did mention page 22 =)
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Of course this facility isn't being installed in the US, but the UK. A quick calulation based on wikipedia's list of power stations in England (not the whole UK, but hopefully representative enough) shows rather larger power stations (the smallest coal fired facility still operational is 1.5GW). I make the avarage for coal and gas fired plants 940MW.
I'm not sure what's driving the difference, possibly a more densly populated country with fewer acceptable locations to site power stations.
And now you have some of the most expensive electricity ever.
If information wants to be free, why does my internet connection cost so much?
bio-fouling happens on moving surfaces as well. It will be expensive keeping them clean.
If information wants to be free, why does my internet connection cost so much?
Yes I do realize that the failure modes are different.
Although your first post was the first time I heard about it.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
Raw and stormy like the early Mayhem or more like in line with Urgehal / 1349 ?
Any link in Metal-archives.com ?
-- 29A the number of the Beast