Stories
Slash Boxes
Comments

SoylentNews is people

posted by LaminatorX on Monday November 03 2014, @11:51PM   Printer-friendly [Skip to comment(s)]
from the plowing-the-sea dept.

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 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."

This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 1) by Bill, Shooter Of Bul on Tuesday November 04 2014, @12:04AM

    by Bill, Shooter Of Bul (3170) on Tuesday November 04 2014, @12:04AM (#112809)

    I don't get that. I don't understand that objection. They don't look ugly to me. Now, if they block a view of the grand cannon or what not, that's not good. But that's more to do with what they are blocking than their own asthetics. I mean, the ones around me are in flat farmers fields. If anything, they improve the aesthetics of the area.

    • (Score: 2) by JoeMerchant on Tuesday November 04 2014, @12:58AM

      by JoeMerchant (3937) on Tuesday November 04 2014, @12:58AM (#112818)

      Everybody has an opinion - and as sure as you like them, others will not, and the beauty of the Democratic process is that people who are upset get to voice their opinions. If the population voting on anything is > 100, you can be certain of dissent - good luck even getting 2/3 of people to agree on ANYTHING.

      --
      My karma ran over your dogma.
    • (Score: 2) by morgauxo on Tuesday November 04 2014, @03:53AM

      by morgauxo (2082) on Tuesday November 04 2014, @03:53AM (#112859)

      Unfortunately the ludites have been breeding and they hate the site of anything technological.

    • (Score: 2) by mojo chan on Tuesday November 04 2014, @08:39AM

      by mojo chan (266) on Tuesday November 04 2014, @08:39AM (#112902)

      It's just NIMBYism. People worried about house prices. Farming some now considered pretty, but wind turbines are not.

      It boils down to them preferring to have a coal plant built by someone else, rather than some turbines near them.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @10:26AM

        by Anonymous Coward on Tuesday November 04 2014, @10:26AM (#112920)

        Interestingly, old windmills are considered pretty. Although they are nothing but the low-tech version of the same thing.

        But maybe they just had the strategy wrong: They should have told the people that it is a modern art project that has the added benefit of generating electricity. :-)

    • (Score: 3, Insightful) by mtrycz on Tuesday November 04 2014, @10:10AM

      by mtrycz (60) on Tuesday November 04 2014, @10:10AM (#112916)

      Just look at those horrendous turbines
      http://i.imgur.com/J6oOgqT.jpg [imgur.com]

      --
      In capitalist America, ads view YOU!
  • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @12:19AM

    by Anonymous Coward on Tuesday November 04 2014, @12:19AM (#112813)

    in locations where there's lots of accessible natural "renewable" (for all practical purposes) energy, it should be taken advantage of

    tidal energy also has two directions; some places have meters of vertical tidal shift, which is like a heavily geared engine that is very very slow but has massive power capacity. some locations have more of one than another. bay entrances (that aren't heavily trafficked by heavy cargo ships with deep drafts) are ideal places to put tidal power stations.

    i personally like the idea of vertical tidal power generators due to slow movement, which means less mechanical wear and danger to marine life, and a much longer rotational source period that (with heavy inertial dampeners such as flywheels) would be much less affected by storm surges and the like than fast-moving horizontal flow that may be prone to over-speeding of turbine shafts in conditions of severe weather.

    there are engineering challenges, but the risks that killed solydra aren't as likely for tidal systems due to specific locality of tidal systems (much smaller market).

    having said that, the power output of tidal generators are never going to replace the need for large non-renewable base load stations, but that's no reason not to continually investigate new possibilities

    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @02:06PM

      by Anonymous Coward on Tuesday November 04 2014, @02:06PM (#112949)

      This unfortunately is a 'the sky is blue and no rain' project at this point. How did they address salt corrosion plus the inevitable barnacle buildup? If they are hard to install they will be even more wicked to fix.

      • (Score: 2) by bootsy on Tuesday November 04 2014, @02:39PM

        by bootsy (3440) on Tuesday November 04 2014, @02:39PM (#112958)

        Scotland has a lot of experience in maintaining large offshore infrastructure. They are called oil rigs and the maintenance is very similar. The only way to really tell how these projects will last is to build them and test them. Funding for offshore tidal energy was cut heavily during the 1980s Thatcher Conservative government. This was a pity as it looked very promising. It's an ideal way of making the remote islands energy sufficient and, given they suffer from power cuts more frequently than the mainland, that is no bad thing.

  • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @12:34AM

    by Anonymous Coward on Tuesday November 04 2014, @12:34AM (#112815)
    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @01:02AM

      by Anonymous Coward on Tuesday November 04 2014, @01:02AM (#112819)

      makes me wonder whether this kind of geared principle could possibly be applied in some way with permanent magnets to generate useful work

      it may have already been tried in various configurations, and no doubt a lot of people would conclude that it would be folly to keep trying due to certain imposed laws of physics, but magnetism is one of those curious fundamental forces of the universe that, while taken advantage of everyday isn't completely understood

      to stop the motion of an electron would require dropping the temperature to zero kelvin which is almost unheard of in nature. despite this, there is no violation of the laws of thermodynamics. call it "not technically perpetual motion, but perpetual motion for all intents and purposes", so it would seem there's also conceptually no technical reason why permanent magnets couldn't possibly convert this latent heat into useful work perpetually (for all intents and purposes)

  • (Score: 2) by redneckmother on Tuesday November 04 2014, @01:22AM

    by redneckmother (3597) on Tuesday November 04 2014, @01:22AM (#112825)

    "The tidal currents are also completely carbon-free"

    Yeah, okay. I can buy that. So is "wind".

    However, I want to know - whether wind or tide based - what is the total carbon footprint for BUILDING and MAINTAINING these "free" industrial plants? I think that the build-out from wind projects in West Texas consume a LOT of carbon in the form of energy-expensive concrete, transportation, construction, and precious water resources (and let's not forget about the energy and other resource expense of producing the machinery).

    What about the disposal costs, once these plants are (inevitably) decommissioned? Who is going to handle it, and how?

    I have long been a proponent of solar (including wind) power, but think that there are a LOT of unanswered questions. The commercial and governmental folk are hot & heavy on these projects (think: lobbying), but the (apparent) winners are the "developers" of the projects - witness the Enron fiasco (check out who jumped on the "wind" bandwagon first in the USA - our buddy Ken, circa 1980).

    --
    Mas cerveza por favor.
    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @01:32AM

      by Anonymous Coward on Tuesday November 04 2014, @01:32AM (#112827)

      if the government stopped subsidizing the oil industry and protecting its overseas interests, there would be a much more level and competitive playing field for renewable energy companies (without needing to prop them up)

      is it ever actually going to happen? probably not. ron paul was likely the last true american statesman for the foreseeable future. his son rand paul seems like a decent guy and he may well prove me wrong, but his dad would have really put the united states on a good economic footing. unfortunately the powerful deep-seated corruptive special interests (which by the way have nothing to do with capitalism) were able to defeat him, but his message will live on and continue to spread in those who understand what's going on and can see over the propaganda that has brainwashed so many.

    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @03:10AM

      by Anonymous Coward on Tuesday November 04 2014, @03:10AM (#112848)

      A typical megawatt wind turbine, makes the energy needed to build it back, in about a year. A wind turbine is designed to last for 20 years. Maybe they will last longer, data is lacking on that.

    • (Score: 2) by RedBear on Tuesday November 04 2014, @06:01AM

      by RedBear (1734) Subscriber Badge on Tuesday November 04 2014, @06:01AM (#112872)

      "The tidal currents are also completely carbon-free"
      Yeah, okay. I can buy that. So is "wind".
      However, I want to know - whether wind or tide based - what is the total carbon footprint for BUILDING and MAINTAINING these "free" industrial plants? I think that the build-out from wind projects in West Texas consume a LOT of carbon in the form of energy-expensive concrete, transportation, construction, and precious water resources (and let's not forget about the energy and other resource expense of producing the machinery).
      What about the disposal costs, once these plants are (inevitably) decommissioned? Who is going to handle it, and how?
      I have long been a proponent of solar (including wind) power, but think that there are a LOT of unanswered questions. The commercial and governmental folk are hot & heavy on these projects (think: lobbying), but the (apparent) winners are the "developers" of the projects - witness the Enron fiasco (check out who jumped on the "wind" bandwagon first in the USA - our buddy Ken, circa 1980).

      I'm always amazed at how frequently this bizarrely illogical objection to renewable energy generation comes up. It's illogical because it implies that the carbon footprint of BUILDING and MAINTAINING an energy generating device that PRODUCES ZERO CARBON during its operating lifetime is somehow going to be just as bad as BUILDING and MAINTAINING an energy generating facility that not only has a non-zero carbon footprint while it's being built and while it's being dismantled but also PRODUCES VAST QUANTITIES OF CARBON during its operating lifetime. One would think that anyone with a functioning brain would understand immediately just how ridiculous the comparison is. Allow me to give a graphical demonstration for anyone still having trouble.

      In the following text-based graph the "#" symbol stands for carbon being released, while the "-" character stands for the carbon-free operation of a facility. We'll be comparing a single coal-fired facility with an aggregate of wind turbines sufficient to equal the same amount of generating capacity.

      Carbon footprint of the entire lifetime of a coal-fired power plant:

      ################################################

      Carbon footprint of the entire lifetime of a collection of wind turbines generating an equivalent amount of energy:

      ##--------------------------------------------##

      Now, this general relationship goes for pretty much all the carbon-zero energy generation technologies such as solar, wind, wave, tidal, etc. There might be a few more hash marks for some of the technologies than there are for others, but I can't imagine any way in which it makes any sort of sense to worry so much about the carbon footprint of carbon-zero energy generation, at least when it's being compared to the carbon-heavy technologies we are currently using. Only once renewables become our primary energy source will it ever make sense to start worrying about which renewable technology has the lowest overall carbon footprint. Until then it is utterly silly to even imply that any form of carbon-zero energy generation could possibly be bad to pursue.

      --
      ¯\_ʕ◔.◔ʔ_/¯ LOL. I dunno. I'm just a bear.
      ... Peace out. Got bear stuff to do. 彡ʕ⌐■.■ʔ
      • (Score: 2) by deimtee on Tuesday November 04 2014, @07:14AM

        by deimtee (3272) on Tuesday November 04 2014, @07:14AM (#112881) Journal
        Assuming that each space represents a fixed amount of energy generation, and each # a set amount of carbon then the argument goes something like :

        Coal fired plant:
        #####--#--#--#--#--#--#--#--#--#--#--#--#--#--#--#--#--#--####
        Total (26x #, 36x -)

        Carbon free power generation of equal capacity:
        ##################--------------------------------############
        Total (30x #, 32x -)

        Numbers are for illustration only, but it is easily possible that a zero carbon power plant is worse than a fossil fuel plant.
        Renewable plants can also entail more quick start-up load balancing plants and/or the costs of using power at non-optimal times.
        Relative maintenance costs may also factor in to it.
        I am in favour of renewables, but they need to be based on valid engineering, not handwavey statements like yours.
        --
        No problem is insoluble, but at Ksp = 2.943×10−25 Mercury Sulphide comes close.
        • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @02:06PM

          by Anonymous Coward on Tuesday November 04 2014, @02:06PM (#112950)

          F#c#i#g M#r#n

      • (Score: 2) by bob_super on Tuesday November 04 2014, @07:15AM

        by bob_super (1357) on Tuesday November 04 2014, @07:15AM (#112883)

        The point is to take everything into account, and get to your conclusion.
        Claiming any power source is carbon-free is a lie, but once you've done the math as you suggest (including base load for discontinuous sources), then you win the argument once and for all (at least against rational people)

      • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @10:32AM

        by Anonymous Coward on Tuesday November 04 2014, @10:32AM (#112921)

        I'm always amazed at how frequently this bizarrely illogical objection to renewable energy generation comes up. It's illogical because it implies that the carbon footprint of BUILDING and MAINTAINING an energy generating device that PRODUCES ZERO CARBON during its operating lifetime is somehow going to be just as bad as BUILDING and MAINTAINING an energy generating facility that not only has a non-zero carbon footprint while it's being built and while it's being dismantled but also PRODUCES VAST QUANTITIES OF CARBON during its operating lifetime. One would think that anyone with a functioning brain would understand immediately just how ridiculous the comparison is. Allow me to give a graphical demonstration for anyone still having trouble.

        You forgot the carbon footprint of actually getting the fuel to the conventional power plant.

        • (Score: 2) by Covalent on Tuesday November 04 2014, @11:22AM

          by Covalent (43) on Tuesday November 04 2014, @11:22AM (#112925) Journal

          Absolutely true, both this and parent.

          Also, fossil fuel plants have heating, lighting, plumbing, cafeterias, etc.

          The question isn't whether wind carbon fossil carbon (it is by a mile). It's whether wind carbon 0. Maybe, maybe not. But still leaps and bounds better than coal.

          --
          You can't rationally argue somebody out of a position they didn't rationally get into.
      • (Score: 2) by urza9814 on Wednesday November 05 2014, @03:28PM

        by urza9814 (3954) on Wednesday November 05 2014, @03:28PM (#113263) Journal

        It's illogical because it implies that the carbon footprint of BUILDING and MAINTAINING an energy generating device that PRODUCES ZERO CARBON during its operating lifetime is somehow going to be just as bad as BUILDING and MAINTAINING an energy generating facility that not only has a non-zero carbon footprint while it's being built and while it's being dismantled but also PRODUCES VAST QUANTITIES OF CARBON during its operating lifetime.

        You are asserting that the following equation can never be true:
        a + b*y 1000*c + 0*y

        Where a is the carbon to build and maintain one coal plant, b is the carbon output per year for a coal plant, and c is the carbon to construct one turbine.

        The building/maintenance isn't comparing apples to apples"-- while I myself think it's probably pretty unlikely, it's certainly not inconceivable that the building, maintenance, and fuel for ONE coal plant might release less carbon than the building and maintenance of ONE THOUSAND turbines.

        The better argument IMO is that the carbon has to come from somewhere. Fossil fuels probably. So how does it make business sense to buy something that requires x megawatts to produce but will itself only produce x/2 megawatts? But then there's price variations between economies and government subsidies for renewable energy and they can charge consumers higher prices...so again, it's unlikely, but possible.

        • (Score: 2) by urza9814 on Wednesday November 05 2014, @03:31PM

          by urza9814 (3954) on Wednesday November 05 2014, @03:31PM (#113264) Journal

          Ah damn it ate my tag...equation of course should have been:
          a + b*y < 1000*c + 0*y

          If a dev is reading this -- in case you aren't aware of this issue, if you type & l t ; in the text area then click preview it shows up correct but converts it to the symbol in the textbox, so when you next choose submit (or preview again) the character disappears.

    • (Score: 2) by Reziac on Tuesday November 04 2014, @07:35AM

      by Reziac (2489) on Tuesday November 04 2014, @07:35AM (#112886) Homepage

      On that same note -- how would the efficiency (cost vs benefit) compare for a whole bunch of small, essentially disposable (and easily replaced) turbines, vs. a few ginormous ones?

    • (Score: 2) by mojo chan on Tuesday November 04 2014, @08:33AM

      by mojo chan (266) on Tuesday November 04 2014, @08:33AM (#112898)

      A better question would be how does the carbon footprint compare with other forms of energy? Clearly they all need concrete and other materials, as well as large construction projects to assemble them. No-one is seriously saying we shouldn't have electricity any more, so the question is how to generate it with the least environmental impact.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
  • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @05:10AM

    by Anonymous Coward on Tuesday November 04 2014, @05:10AM (#112865)

    for people to start crying when the sea critters fly, i mean swim into them.

    • (Score: 2) by bob_super on Tuesday November 04 2014, @07:13AM

      by bob_super (1357) on Tuesday November 04 2014, @07:13AM (#112880)

      The point is to have a shark farm on either side of the plant.
      People can't see well under water, you just need to deal with the injured's bodies and you're safe from scrutiny.
      Bonus: you can release sharks, sell shark fin soup, and Greenpeace will twitch in the corner as they can't object.

    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @08:38AM

      by Anonymous Coward on Tuesday November 04 2014, @08:38AM (#112901)

      Yeah, it's not like we have entire fleets dedicated to exterminating all sea life roaming the seas...

  • (Score: 2) by hoochiecoochieman on Tuesday November 04 2014, @03:19PM

    by hoochiecoochieman (4158) on Tuesday November 04 2014, @03:19PM (#112967)

    Please get your units straight! The whole summary is a mess of metric and other systems. It's painful.

    I sugest you put this in your editorial rules: Using the metric system as default for every post, and putting other systems in parenthesis as a courtesy to the metric-impaired. Or the other way around. But mixing km, miles and knots like a Russian salad, please don't!

    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @03:42PM

      by Anonymous Coward on Tuesday November 04 2014, @03:42PM (#112972)

      Agree

    • (Score: 0) by Anonymous Coward on Tuesday November 04 2014, @09:08PM

      by Anonymous Coward on Tuesday November 04 2014, @09:08PM (#113059)

      - knot is the commonly used unit of nautical speed
      - km/hr is the common (metric) unit of wind speed

      you could possibly argue the units that tides are measured in, but in this day and age at least some familiarity with both metric and imperial units isn't an unreasonable expectation

      it also can in some cases depend a little on the units used by the source, as i've seen some ridiculous arguments in wikipedia talk pages about conversion of units being used to imply a different conclusion to a source (for example, converting to a unit that makes a number "appear" larger), so editors must be cautious not to inadvertently engage in 'synthesis'

      anyway, just saying. i do agree that we should aim for a high editorial standard at SN, but it will always be impossible to keep everyone happy all the time

      i'll chuck something about this on the SN wiki editorial policy page. feel free to join up and review/contribute to it yourself too

      • (Score: 2) by hoochiecoochieman on Wednesday November 05 2014, @11:15AM

        by hoochiecoochieman (4158) on Wednesday November 05 2014, @11:15AM (#113199)

        knots are mixed with km/h and mi/h. It doesn't make sense. Even if, as you say, "some familiarity with both metric and imperial units isn't an unreasonable expectation", was true (and it's not), a decent style would be using the same measurement unit consistently everywhere, with parenthesis to display alternative units.

        Given that:

        1. 96% of mankind use the metrical system.
        2. This is a website dedicated to science and technology.
        3. Science worldwide uses the metric system.

        It would be reasonable to use this one as the default.