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Science Technology

Underwater Ocean Currents Used to Power Bermuda 115

Posted by ScuttleMonkey from the power-and-sushi-all-from-one-machine dept.
Saevio writes to tell us The Royal Gazette is reporting that Bermuda is planning to sink a power generator off the coast to take advantage of ocean currents. The company providing the service, Belco predicts that they will be able to provide approximately 10 percent of the island's energy needs. From the article: "The 150ft long deep sea generator with a four-blade turbine inside would cut Belco's dependency on oil and also benefit the environment by cutting future fuel emissions, he added, stating that the company needed to increase its generating capacity before 2010. Mr. Madeiros, who hailed the technology 'mind-boggling', said: 'This is cutting edge technology, not used anywhere else. One can't help but get excited by this technology.'"
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Underwater Ocean Currents Used to Power Bermuda More

Underwater Ocean Currents Used to Power Bermuda

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  • Original press release (Score:5, Informative)

    by luder ( 923306 ) * <slashdot@[ ]as.net ['lbr' in gap]> on Wednesday February 15, 2006 @10:37AM (#14724574)
    Belco's original press release [belco.bm].
    • I wonder how fast it spins....sushi anyone?
       
      Seriously, I'd like to see their solution for protecting marine life from it. Obviously the fan is cowled, but they don't mention any sort of grating to keep the fish out, I'm sure they did something... Also, does it work off of tidal currents? Or some other deeper current?

      • Re:how fast (Score:5, Interesting)

        by Rei ( 128717 ) on Wednesday February 15, 2006 @10:59AM (#14724758) Homepage
        Probably a fraction of one RPM. Not to mention that most fish have pressure-sensitive organs, and they flee from unexpected motion.

        My worries would be about the effects of sapping gulf stream energy (that is what this is using, right?) would have on the stream. This is probably a tiny fraction of it's total energy, but if this sort of thing becomes widespread, it can only serve to slow the vital gulf stream (climate regulation, mineral distribution, etc).

        • Re:how fast (Score:3, Informative)

          by Rei ( 128717 )
          Er, I meant RPS, not RPM, but whatever.

        • Re:how fast (Score:5, Insightful)

          by Hercynium ( 237328 ) <Hercynium@gm a i l .com> on Wednesday February 15, 2006 @11:34AM (#14725052) Homepage Journal
          It's an interesting conjecture, but probably more or less akin to the idea that windmills may change weather patterns.

          Except for solar energy, the energy in this planet is somewhat of a closed system. The trade-off: Possibly affecting an ocean current may well be much better than the effects of smog, mining.

          I won't pretend to know nearly enough about such things, but just considering the volume of water moving in the ocean, I believe it would take an incredible number of turbines like this to measurably affect any ocean current.

          As far as the fish are concerned, you are correct, a current-driven turbine poses little danger to them, unless it somehow messes with the temperature or causes some sort of pollution. (something I actually know about for a change)

          • I dunno, this thing looks like it's gonna take up half the ocean [theroyalgazette.com] according to the picture! This will almost definately slow down the ocean. The oceans will freeze! Think of the children! Of the fishes, I mean. The fish children. They'll be so cold.
          • Oh, yeah one other thing - the fishes 'motion sensors' - commonly part of the 'lateral line' (pulling from memory, may be wrong) can be affected by electrical currents. Even teeny ones. Just laying it out there. I don't think it's a big deal.
        • I doubt this would have an effect- but have they considered the fact that global warming may well eliminate the Gulf Stream entirely in the next 10 years? Without that bunch of ice in the north, the convection current propelling the gulf stream's counter-clockwise motion simply won't happen.

          • Re:how fast (Score:3, Informative)

            by SEE ( 7681 )
            Um, no, temperature changes will not eliminate the Gulf Stream entirely. The northern split-off extension of the Gulf Stream called the North Atlantic Drift is thermocline-driven, but the rest of the Gulf Stream is just the inevitable effect of the Earth's rotation -- the Coriolis effect [wikipedia.org] on the current-driving winds.
        • For every action there is an equal and opposite reaction. However, the resulting environmental impact from this form of energy generation can't help but be cleaner, if not also less harmful overall to the environment than, well, just about anything else. The heat and pollution emissions of traditional powerplants affect the weather around them, and I doubt very seriously that erecting anything short of something the size of the Great Wall of China would even remotely affect the oceans currents. And Rei is

        • My worries would be about the effects of sapping gulf stream energy (that is what this is using, right?) would have on the stream. This is probably a tiny fraction of it's total energy, but if this sort of thing becomes widespread, it can only serve to slow the vital gulf stream (climate regulation, mineral distribution, etc).

          No worries at all, actually. There will be a sudden loss of signal from the generator, and when we go looking, we will discover that yet another artifact has mysteriously vanished i

      • The depths are a hundred meters. I suspect that like wind generators, they are looking to take advantage of normal currents. In this case, the gulf stream. The nice thing about it is that the currents should be fairly consistant.
    • Current to Current Corporation based in Mass. Does anybody have any details about them.

  • Won't this slow down the current? (Score:4, Interesting)

    by aapold ( 753705 ) * on Wednesday February 15, 2006 @10:38AM (#14724583) Homepage Journal
    I mean, the energy that otherwise would keep pushing warm gulf stream water towards Europe, that's going to be harnassed by Bermuda...

    Does this not risk at slightly lowering the temperature of Europe?

    I mean you never know the full consequences... I know, we have global warming to offset that, but still... (and these diverted warmer waters will linger in the southern atlantic, so mean global temperature is still the same...)
    • It's 150 feet long. I'm sure that there's nothing to worry about in that respect. If you're talking something the size of the State of Florida or the entire size of the UK, then maybe you'll have something to think about.
    • Comment removed based on user account deletion

      • Re:NO, IT WON'T. (Score:3, Funny)

        by rpjs ( 126615 )
        Yes. Why is it you can never find a Total Perspective Vortex when you really need one?

      • Re:NO, IT WON'T. (Score:5, Insightful)

        by paeanblack ( 191171 ) on Wednesday February 15, 2006 @11:00AM (#14724773)
        For crying out loud, why is it every time there's a story about wind power, or ocean thermal power, or any other non-polluting technology, we always get somebody with NO concept of SCALE popping up with this same asinine question?

        Because people are dumb. One turbine in the ocean is, literally, a fart in a hurricane.

        On the other hand, don't blindly assume humans won't overbuild something. Do you think the first internal combustion engine spurred thoughts of smog-filled valleys hundreds of miles long? No, because it would take tens of millions of combustion engines running non-stop to do such a thing.

        • Re:NO, IT WON'T. (Score:5, Insightful)

          by LWATCDR ( 28044 ) on Wednesday February 15, 2006 @11:56AM (#14725252) Homepage Journal
          "On the other hand, don't blindly assume humans won't overbuild something. Do you think the first internal combustion engine spurred thoughts of smog-filled valleys hundreds of miles long? No, because it would take tens of millions of combustion engines running non-stop to do such a thing."

          Yep that is the key. It really is all a matter of scale. How much will be too much. Right now I wouldn't worry. What we need to do is see if it is practical. If so then we need to figure how much we can extract without causing damage.

          As one person said, "The solution to pollution is dilution". A little bit here energy taken from here and moved to their will not really matter much.

          It is exactly like the wind power issue. One windmill isn't going to hurt anything. What happens when you start extracting mega watts out of the wind pattern? What about changes to the micro climate just down wind from the wind farm?
          I worry more when people dismiss things like that without looking at them at all because it would be too small to matter. Sort of like the idea that foam that you can crumble in your hand could shatter a carbon-carbon leading edge tile. I mean the foam when it hits that hard material will just shatter doing no harm right?
          • Comment removed based on user account deletion

          • Re:NO, IT WON'T. (Score:5, Informative)

            by radtea ( 464814 ) on Wednesday February 15, 2006 @03:07PM (#14726657)
            What happens when you start extracting mega watts out of the wind pattern? What about changes to the micro climate just down wind from the wind farm?

            The latter is irrelevant to all but the people who live there, in the same way the shadow effects of any industrial plant are irrelevant to any but the people who live there. It is not an environmental issue as normally understood--it is a land use or zoning issue. This is not to say it isn't important--it is--but we have centuries of law dealing with things like this, so there are really no signficant unknows with regard to wind farms except for the possibility that they do not have any significant negative downstream effects. That's a pretty good kind of uncertainty to have: "Nothing bad might happen! We just don't know!"

            With regard to the question of what happens when we start extracting megawatts from the wind, this is a question that can be answered on the back of an envelope, which I will now proceed to do. Air has a density (rho) of about 1 kg/m**3. Consider wind at 10 kn, which is about 5 m/s. The power per square meter is 0.5*rho*v**3, or about 60 W, of which about half is available to windmills. Wind power has an energy density of about 30 W/m**2, maybe as high at 100 W/m**2 in windy areas. The Canadian province of Ontario has a winter load of about 20 GW and a summer load of about 25 GW. So we're talking about at least 200 million square meters of swept area to accomodate all of it, and maybe over three times this much. This is equivalent to a line of windmills with 100 meter span, 2000 km long removing half the kinetic energy from all the air that passes through them. This is not a small environmental influence. It is hard to imagine that this would not quite fundamentally change energy transport and therefore weather patterns over hundreds of kilometers.

            I didn't expect that result when I started writing the paragraph above, but since I'm a scientific rather than a religious environmentalist, I can't simply ignore it. Wind power is still worth pursuing, but it is very clear that it is never going to be more than one element in a mix of alternatives, and is very unlikely to ever generate more than 10% of our power if its environmental impact is to be kept moderate.

            • Re:NO, IT WON'T. (Score:3, Interesting)

              by joggle ( 594025 )
              I would like to see that number in context though. How much energy is lost due to fixed objects on the ground? (forests, buildings) It would be interesting to try adjusting the ground resistence in a weather model to see what the effect would be of having a large number of wind turbines. Any atmospheric science students/graduates out there willing to play with their weather models?

            • Oops (Score:4, Informative)

              by radtea ( 464814 ) on Wednesday February 15, 2006 @04:12PM (#14727200)
              Wind power has an energy density of about 30 W/m**2, maybe as high at 100 W/m**2 in windy areas.

              Reviewing my own estimate, this number is obviously very sensitive to the average wind velocity, which comes in as the cube. It turns out that average wind speed data for Ontario are available [ontariowindatlas.ca], and my estimate of 5 m/s is on the low side for coastal regions. But even with a more optimistic 8 m/s we are still talking 125 W/m**2 after efficiency considerations, which is only a little higher than my 100 W/m**2 high-end value.

              It is also clear that placing wind turbines along the shore will have the lowest environmental impact, because the wind is giving up a lot of energy there in any case.
            • But you see my point. If one doesn't worry about things when they are small they have a habit of sneaking up on you.
              I am not a fan of wind power. It is too unpredictable, maintenance on wind turbines is not cheap, and can have a sever impact on the local quality of life. In many ways it reminds me of dams. They where once thought to be the perfect clean energy source.

              To not look for potential problems before they happen is .... foolish?

            • I forgot to ask. Did your calculations include the efficiency of the wind turbines? A good part of that potential energy will be lost. I have not looked into the average efficiency of a wind turbine but I would guess that it could be as low than 20%.

        • Re:NO, IT WON'T. (Score:5, Insightful)

          by fireboy1919 ( 257783 ) <rustyp@NosPAM.freeshell.org> on Wednesday February 15, 2006 @01:51PM (#14726156) Homepage Journal
          One turbine in the ocean is, literally, a fart in a hurricane.

          I think not! An ocean turbine is literally an mechanical device, while the ocean is literally a body of water.

          Turbines are not now - nor have they ever been - farts. And while a hurricane is also mostly water, an ocean is not one.

          Literally is not another word for figuratively; it's the opposite.

          Literally.
          • My brother once complained to me about the misuse of the word 'literally'. It was about something along the lines of "literally shoving it down my throat". When he was done venting, I told him "That literally sucks balls."
          • You need to update your dictionary or get out more. Most modern dictonaries acknowledge that the word "literally" is commonly used at a general intensive, and most of those folks in the big blue room agree.

            If you want to get pedantic, pick a battle you can win.
        • ...I do not think it means what you think it means.

          Though that is a common mistake. [reference.com]

    • Re:Won't this slow down the current? (Score:5, Interesting)

      by scheming daemons ( 101928 ) on Wednesday February 15, 2006 @11:00AM (#14724764)
      Imagine a cookie crumb on your living room floor. That's the relationship that Bermuda has to the Atlantic ocean.

      Now, imagine a speck of dust 1/100th the size of the cookie crumb in your living room. That's the relationship of this turbine generator to the Atlantic ocean.

      This turbine generator off the coast of Bermuda will have the same effect on the Atlantic ocean currents that the above-mentioned speck of dust will have on the wind currents in your living room.

      So small as to not even be measurable.

      • So lets say, for a perspective... How many of these turbines are needed to generate 100% of the planets energy need? Or 1%? And how much energy do you have to take out of the gulf stream for an effect on temperature in europe? Or any other effect? 10%, 1% or 0.1%? How much is that in GW?

        It is easy to see that one device like this will make no difference. But it is not easy to see how far you can go.

      • Re:Won't this slow down the current? (Score:5, Informative)

        by maggard ( 5579 ) <michael@michaelmaggard.com> on Wednesday February 15, 2006 @12:49PM (#14725718) Homepage Journal
        A crumb on your living room floor is a great way to put Bermuda in context of the Atlantic.

        However it doesn't work so great in context of the Gulf Stream.

        The Gulf Stream is not some huge tide-like current hundreds of kilometers wide, instead it's typically only a kilometer or two wide. Indeed if you fly over it (I have a number of times) it appears as a clearly defined 'river', of a much different color then it's surrounding waters, with large swirls & eddies sometimes breaking off of it, cutting through the otherwise featureless ocean.

        So while Bermuda may be a crumb the Gulf Stream is a spider strand.

        That said I don't think putting a few turbines, or even 'a lot' will have significant effect on it. The total energy in it is incredible and it's an ongoing process, there's not some hose at one end that can be cut off stopping it all, but rather a push & pull process that keeps the whole thing going. Even if Bermuda were able to pull out 1% of the energy in it that would be less then the effect of a slightly windier or cloudier day in the Gulf on it, completely lost in the noise level.

        By the way, if you're ever on the East Coast of the US & have some friends who fly ask them to take a gander next time they're over the seashore for any eddies off of the Gulf Stream that are close to the shore. They're much lighter colored then the usual cold dark blue Atlantic waters, easy to spot. If there are any by a beach then take the opportunity to go swimming in it - it's amazing. Cold cold cold Atlantic waters then suddenly bathwater warm, often with tropical fish trapped inside the thermocline. I've enjoyed a few off of Provincetown, Mass. (tip of Cape Cod) and they're times I treasure , and friends who were along retell of the experience over & over.

        • The Gulf Stream is not some huge tide-like current hundreds of kilometers wide, instead it's typically only a kilometer or two wide. Indeed if you fly over it (I have a number of times) it appears as a clearly defined 'river', of a much different color then it's surrounding waters, with large swirls & eddies sometimes breaking off of it, cutting through the otherwise featureless ocean.

          I guess these [wikipedia.org] maps and images are dead wrong. And who knew the U.S. Naval Oceanographic Office [weatherimages.org] would have such an err

      • I have a den you insensitive clod!
    • Others have already explained, that yours fears are totally unsubstantiated, but you are wrong also on global warming offsetting this, global warming also slows down oceanic currents, by melting polar ice caps, because the water coming from the melted ice basicly reduces overall salinity of water near the caps.
    • Keep in mind that the current flows out of the gulf and around the tip of Florida. Right at that point is probably some of the strongest currents. If Florida was smart, they would sink a few of these off the keys. But it will probably take a change in the current Florida admin. before that will be allowed.
      • f Florida was smart, they would sink a few of these off the keys. But it will probably take a change in the current Florida admin. before that will be allowed.

        Yeah - it would take a change to someone who was dumb on the concept of cost/benefit analysis.

        • Yeah - it would take a change to someone who was dumb on the concept of cost/benefit analysis.

          I don't see how that changes his point.... It would be sort of like the US goverment not allowing the IRS to setup a web page to do peoples taxes because it will complete with the tax preperation companies. Even though the IRS pointed out that it would save the goverment money because more people would file online, and its cheaper than having people opening envelopes and scanning tax returns.
    • Does this not risk at slightly lowering the temperature of Europe?

      And communication satellites slightly slow down the rotational speed of the earth.

      But nobody cares.

  • Mindboggling, indeed (Score:2, Funny)

    by Anonymous Coward
    Just how many current-surfing turtles and fish can we expect to be missing from Finding Nemo 2 because they get swept into the four turbines?

  • Next headline about the project (Score:5, Funny)

    by maxwell demon ( 590494 ) on Wednesday February 15, 2006 @10:40AM (#14724601) Journal
    Power generator mysteriously vanised in the Bermuda sea!

  • cutting edge technology... (Score:5, Funny)

    by aapold ( 753705 ) * on Wednesday February 15, 2006 @10:40AM (#14724604) Homepage Journal
    I prefer to say "current" technology.

    I suppose this begs the question if they are going to be alternating currents or just using a direct one.

  • Does anyone know... (Score:4, Funny)

    by daranz ( 914716 ) on Wednesday February 15, 2006 @10:45AM (#14724639)
    What will be the impact of this on the performance of the triangle? I wouldn't want to see halves of ships dissapparing all of a sudden, because there isn't enough power...

  • Hoping the company lives up to promises (Score:5, Interesting)

    by ursabear ( 818651 ) on Wednesday February 15, 2006 @10:52AM (#14724695) Homepage Journal
    From TFA:Asked about the potential impact on Bermuda's unique reefs, she said the efficient generator would have a "very low" environmental impact and said the noise produced by the generator would be "very, very quiet" and would not impact sea creatures. She said the unit would be sunk past the first layer of marine life, and fish below that level would be able to safely swim through it. An electric cable would link the substation to the generator under the sand.

    I guess this means that the generator blades spin slowly enough that the fish just swim around the blades? My first thoughts before RTFA were concerns for the reef's health. I would hope that they would design it such that it would not cause a sort of in-the-ocean-current observer effect [wikipedia.org].

    I'd like to see the opining of those with some physics or ocean dynamics experience.

    It sounds like a great idea... I wish we had lots more three finkers out there trying to make power in new ways.
    • Keep in mind that it's the water pushing the blades, not the blades pushing the water...this is not like a ship screw.

      Under steady-state conditions, a neutrally bouyant object will be pushed, by the current, through the whole turbine without ever touching it. The same water that is moving the objects is pushing the turbine blades out of the way.

  • I'm too tense (Score:3, Insightful)

    by jfengel ( 409917 ) on Wednesday February 15, 2006 @10:54AM (#14724715) Homepage Journal
    Perhaps "Underwater currents TO BE used..." would make a better headline. It's four years before they deploy it. Save the past tense headlines for when I can ask questions like "Does it work?" and "Are there any unintended side effects?" and "Would it scale?"
  • But what will they do when they've used up all the ocean's energy and the water doesn't move anymore?!?
  • Sid Meier was very forward looking. Tidal generators anyone?

    Ok, maybe not the same as tidal generators but pretty close and, presumably, a bit more consistent.
  • The use of tidal currents will result in a gravatational drag on the moon. Over a long enough time period, the moon will begin to spiral closer and closer to the earth, finally crashing into the planet.
  • That way they'd furnish all their power needs.
    • I would be surprised if they did not install other power generators as well. Bermuda has some nice trade winds. A few nice wind generators and solar cells combined with a few more of these may enable them to be fairly energy independant.

      • I would be surprised if they did not install other power generators as well. Bermuda has some nice trade winds. A few nice wind generators and solar cells combined with a few more of these may enable them to be fairly energy independant.

        Bermuda is a pretty damned small place (20.75 sq miles according to their website). I don't think they have a trmendous amount of land area to go putting up wind farms on.

        Now, if they could get their wind turbines floating out to sea (I'm sure this was posted on Slashdot a

  • ...and also benefit the environment by cutting future fuel emissions.

    But what is the environmental impact of changing the ocean's current? Proponents of tidal/wind power never seem to address this. You cannot create energy from nothing. Generators like this are converting one sort of energy to another. Which means that in "creating" electricity, we are robbing kinetic energy from the ocean's current (or air's current, in the case of windmills). That has to have some sort of impact on the environment, but t

    • IIRC, (it's been a long time since school) the currents are produced by temperature gradients. It seems to me that as long as the temperature gradient exists, currents will be produced. I don't think that water's temperature moving through a tiny turbine will be moderated enough to even be detectable. Even if you had 1000 of these things, let's say we're taking about a total cubic footage approximately 1.2MCF (given a base radius of 50' and a height (length) of 150') for each, which means we have a total

  • Old Tech (Score:1, Informative)

    by Anonymous Coward
    As a matter of fact, yachts these days fairly often have immersed generators. As the yacht gets hauled along by wind power, the generator trails and spins in the water.

    They generate quite impressive amounts of electricity at the cost of a knot or two in speed.

    Mind you, the water speed of those trailing generators is considerably higher, quite often, than the gulf stream, but it's quite enough for some impressive juice.

  • Morons! (Score:2, Interesting)

    by RecycledElectrons ( 695206 )
    The issue is not hurting fish! Velocity has to be relative to something. From the fish's perspective, the turbine's velocity is relative to the ocean's water. A 150 foot long turbine will spin close to the speed of the ocean water. It will have less velocity vs. ocean water than will a coral reef!

    The issue is not stopping the currents! An island in this location would scarcely be noticed, and the turbine will do MUCH less than an island to stop the ocean's flow!

    At least it's far enough down to not get destr

    • The issue is...one turbine generates 10% of the power for an island...and then it gets rusty. He he he....maintenance is a b!tch, then she gets PMS. Imagine loosing 10% of your generation capacity instantly.

      Wow - power plants require maintenance have downtime....

      That is modded as "Interesting"? To who?!

      Most waves only travel along the surface...I wonder what a good, strong underwater (tsunami-type) wave would do to it?

      Nothing.

      Seriously, absolutely no effect.

      It's not "most waves only travel along th

      • >> The issue is...one turbine generates 10% of the power for an island...and then it gets rusty.
        >> He he he....maintenance is a b!tch, then she gets PMS. Imagine loosing 10% of your generation
        >> capacity instantly.

        > Wow - power plants require maintenance have downtime....

        They all have maintenance requirements. However, a single plant being 10% of your capacity makes taking it down for maintenance a costly endeavor. I would recommend several, smaller plants so that they can be taken down
  • I don't know much about ocean currents and how they work, but my electricity driven mind makes me think that putting a bunch of turbines in the middle of the ocean current will cause the current to adjust its path to go around them. Right?

  • Comment removed (Score:3, Insightful)

    by account_deleted ( 4530225 ) on Wednesday February 15, 2006 @04:17PM (#14727249)
    Comment removed based on user account deletion

  • effects could be catastrophic (Score:3, Interesting)

    by TRRosen ( 720617 ) on Wednesday February 15, 2006 @05:26PM (#14727906)
    We have no ideal what this could do. This is not like a windmill which pull energy from surface winds. This is akin to a 10,000 foot high windmill placed directly in the jet stream. This is also not like tidal or wave generators for the same reasons those devices capture energy that would have been expended by waves crashing on shore and slowly eroding beaches. This device will pull energy from currents that effect weather and climate world wide. If it were just to shift the current a few miles on the east coast it could shift the currents hundreds of miles in the north sea dramiticly changing regional climates. Also note that even the biggest aircraft carriers have no effect on these currents as the ships sit less then 10 meters below the water.
  • There is the Seaflow [vatech.at] project in the Bristol channel (that's England / Europe), which does pretty much the same thing. There is at least one more of these underwater ocean current devices that I don't remember, and I've recently visited the Enermar [pontediarchimede.com] system in the Strait of Messina. See this Uni Strathclyde site [strath.ac.uk] on more details.
    A good Google search term is Ocean current energy, or Marine current energy.

    Enough Karma Whoring for this time! It's a pity they won't go with offshore wind energy - the resource at the

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