Giant Deep Ocean Turbine Trial Offers Hope of Endless Green Power - Slashdot

Posted by EditorDavid

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  Disrupt the ocean currents. What could possibly go wrong?

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  • The amount of energy humans require is peanuts compared to the amount of kinetic energy in even a single ocean current with trillions of tons of water flowing. You might as well say wind farms disrupt the atmosphere.

    However one issue they will have - other than chopping up fish - is that certain types of sea life just loves anything man made that looks like a reef or a rock. Its going to require regular cleaning and in the deep ocean that isn't going to be a simple task.

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    • However one issue they will have - other than chopping up fish

      (resists temptation to make a joke involving sushi bars)

    • Re:

      That was my first thought. Ocean-based equipment (especially ones with moving parts) are susceptible to things that aren't issues on land (barnacles, sea water, sea turtles, whales, kathalu,...).
      Also, if you try to filter out fish you'd likely interrupt the current that your power generation is based on. Not to mention (as you said) maintenance and repairs are going to be far more expensive than land-based solutions. Hopefully they nail all that down so we can take advantage of earth's energy sources.

      • Re:

        Sorry Kathalu, I misspelled Cthulhu and ended up with you by virtua of the auto-correct gods... maybe it's a sign...

      • Re:

        Yep. I can imagine giant squids getting entangled in this will be a constant problem.

      • Re:

        Turns out it's only 30 to 50m down, which is really not very deep at all.

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          Maintainable with scuba with a special air mix then. Its like painting the golden gate bridge. Every day paint a small bit and when reaching the far end return and start over. So every day send down a pair of divers with wire brushes to scrape one square meter each. At a moment of slack current of course.

          • Re:

            Might have to disable the turbines while scrubbing/maintaining them.

            • Re:

              Well that's one of the benefits of a slack current. It makes the approach and staying on station a bit less complicated.:-)

              • Re:

                Ah, true. They could probably lengthen the tethers holding it down so it could rise to the ocean surface for more efficient and cheaper maintenance. Then retract the tethers again to get it back into position.

    • • Re: No it won't.

        Yeah ofcourse it's something these engineers haven't thought about, after finishing a successfull protype run. If you can think of it, people's who's job it is and experience with machines designed for working in sea certainly will.

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          You mean don't keep creating naval rated versions of things like we have been doing for the past two thousand or more years?

        • Re:

          Hey, they're feeling self-righteous and smart, while shitting on people accomplishing things.

          That said it would make a cool article. Nanomaterials and electric currents both prevent barnacles, so maybe one of those is being used.

    • Re:

      There is a whole industry dedicated to keeping fish and plant life out of places it is not wanted. Nuclear power plants, for example, need a supply of water for cooling and it's not good if it gets clogged up with plants, algae or fish. It involves UV light, underwater speakers and bubble curtains.

      • Re:

        Nuclear power plants, for example, need a supply of water for cooling and it's not good if it gets clogged up with plants, algae or fish. It involves UV light, underwater speakers and bubble curtains.

        And yet, zebra mussels [chicagotribune.com] are able to shut down nuclear plants [deseret.com] when the intake pipes get clogged [army.mil].

        • Re:

          Your articles are all about how an invasive species started causing problems with systems that were not designed with it in mind, and how additional systems are being installed to deal with the problem.

      • by Solandri ( 704621 ) on Saturday June 11, 2022 @01:39PM (#62611778)

        The cooling inlet for a nuclear plant is barely big enough for a scuba diver to enter. It could probably be smaller, but they make it that big so a scuba diver can regularly go in there to clear it of fouling by biological organisms (mussels, seaweed, etc). What they're proposing here is on an entirely different scale. The marine industry spends billions on anti-fouling paint, and it still requires regular scraping (every few weeks to months) and repainting (every few years). It's a massive endeavor. I suspect the best solution is not going to be propeller-like turbines, but something more like a flapping tail. It will be less efficient but will continue to function even if heavily encrusted, allowing you to stretch out maintenance intervals to where they're economically feasible (it costs probably one or two orders of magnitude more to send a diver down to clean things than to send a maintenance worker to a wind turbine).

  • Disrupt the ocean currents. What could possibly go wrong?

    Two possible solutions:

    1. Level one or more undersea MOUNTAIN RANGES that block the currents more than humans could hope to.

    2. Improve science and math education so people can understand why this isn't a problem.

    Solution #2 is far more cost-effective.

    • Re:

      Probably won't be a problem for the half of the US population that embraces, or at least recognizes, science and math, instead of treating it like elitist nonsense... On the other hand, that first half is probably already there and on-board.

  • Out of sight, out of mind relative to disruption

    Not just currents but the local eco system as well. When wind turbines kill eagles we see it. When deeps see turbines somehow effect the local ecosystem negatively its not a problem since it is out of sight. Corporations will love this "out of sight" feature.

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    • • Re:

        Really, reality does not say its better for a company to operate its machinery out of sight of the public? Apologies if such inconvenient truths offend your narrow mind.

• They didn't keep breaking down..
  .

  • Re: If only...

    And you this because? Nirmally when designing a system like this, maintenance and replacement are factored into the costs of operating a site like this. It's probably easier to maintain and operate a few large turbines like this as it is to operate a nuclear site or even a coalbased site.

    • Re:

      He is saying that because that is what has happened to many tidal generators in the past. There is one sitting defunct in the Bay of Fundy right now, waiting for someone to remove it (the company that built and installed it has gone bankrupt, so they won't be doing it).
      Here is some info on the history of generators at test sites there, taken from ATV News (local Atlantic Canadian news source):
      "The Bay of Fundy has been the site for several tidal turbine demonstration projects over the years. In 2009, an in-

      • Re:

        You base it on one bad example which had a problem of the company going bankrupt due to other reasons and because of that the turbine in the stream was left unsupervised from the day the company was closed. We don't know how it got damaged. And you really don't think previous versions of doing this haven't been taken into account when designing these new turbines? Let's just see what these newly designed generators will bring. It would be very foolish, naive and even incompetent if the designers of these ne

  • Horses, 130 years ago

    Said the horse owners about automobiles 130 years ago.

• ... that I am deeply dissapointed with the editors wasting their opportunity to post the same story three times in a row.

  Are you sure the processor in these turbines is not an Apple M1 with some security fault just discovered?

  • Re:

    No, these are *Slashdot* Editors. So this is about a sucerity fault in the Aplle M2 procession.

  • Well its an unannounced Apple Silicon, so NDA

    The turbine manufacturer has not cited what processor they use. Apple still considers that particular Apple Silicon model an announced version and the manufacturer to be under NDA.

• Fukushima squashed the nuclear renaissance but Japan will overcome its nuclear fears and meet its climate goals by restarting all the nuclear plants that were closed.
  https://www.japantimes.co.jp/n... [japantimes.co.jp]
  Now if only Germany could do the same.

  • Re:

    Nothing has to be done to squash fantasies. They fade with time, and unfulfillment. Nuclear specializes in both of those things.

    They have no other practical choice except offshore wind, which they are already doing.

    • Re:

      Not really, its more of a political interference. Like when Clinton shut down US nuclear research to say thank you to the "Greens" who supported his campaign. Quid pro quo.

• Cost? (Score:4, Interesting)

  I found no mention of either the cost to build or the cost to run / price per kWh. I always approach new power tech with a healthy dose of skepticism until the inventors can demonstrate:

  1. Unit Economics - Will the price per kWh be competitive now or at scale?
  2. Scalability - Can you make enough of these to satisfy a country or a continent?
  3. Time to Market - Is this a pipe dream or are you actually delivering?

• The question to ask is where does that energy come from. Of course "from the sun" is correct, but that is also true for fossil fuels. If that ocean-stream has been fueled by the sun for millennia and now contains 10EJ of energy, then tapping 60GW will deplete that storage in about 6 years. That's not "endless green energy".

  The problem (I htink) is that nobody knows how much energy is stored in such ocean currents. And even less about how they are fueled by the sun. For all we know, the current was started

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  • Re:

    I think it's primarily from the kinetic energy of the planet's rotation. The tides result from gravitational interaction with the sun. This is going to hasten the slowing of the earth's rotation over the next gazillion years.

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      The tides result from gravitational interaction with the sun.
      
      The main cause of the tides is the Moon. Yes, the Sun is much bigger, but it's also farther away, and the tidal force is inversely proportional to the cube of the distance, rather than the square.

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    We know quite a lot about what drives currents. Earth's rotation, wind, gravity, temperature, and salinity are the primary causes. Temperature is influenced somewhat predictably by insolation, sea ice is also involved and there is the rub because it's going away. As such, ocean currents which depend on it (including "the conveyor [wikipedia.org]", the dominant ocean current) are slowing [aljazeera.com]. The idea that currents are dependable is nonsense. They were, until we perturbed the system egregiously. Now they are in a process of rap

    • Re:

      If this can shut down a few coal plants then it'll help to reverse that trend.

• "The deep ocean is generally defined as the depth at which light begins to dwindle, typically around 200 meters (656 feet)."
  https://oceanexplorer.noaa.gov... [noaa.gov]

  • Re:

    I'm sorry, but you're too late - all the promotional materials have already been proofed and sent to the printers. We're just going to have to ride it out...

• Another stratagem in the hope-a-dope way to win eyeballs.

• Try to convince someone to shut off the lights when they leave the room. How many instant-on things are sipping power right now?

• It's still quite a long way between where they are now and that 200 gigawatt dream. From TFA:

  "The tests proved the prototype could generate the expected 100 kilowatts of stable power and the company now plans to scale up to a full 2 megawatt system that could be in commercial operation in the 2030s or later."

• I wonder what dimension the "Giant" in the title refers to. Underwater current turbines are typically much smaller than wind turbines, due to material stress caused by the much denser medium. 330 tons is also not quite "giant" for a turbine.