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Power

28-Ton, 1.2-Megawatt Tidal Kite Is Now Exporting Power To the Grid (newatlas.com) 65

Minesto, a marine energy tech developer based in Sweden, has deployed their new Dragon 12 tidal energy harvester to the Faroe Islands. Operating like an underwater kite, the Dragon 12 "uses lift generated by tidal flows to fly patterns faster than the currents, harvesting renewable energy," reports New Atlas. From the report: Where devices like Orbital's O2 tidal turbine more or less just sit there in the water harvesting energy from tidal currents, Minesto's Dragon series are anchored to the sea bed, and fly around like kites, treating the currents like wind. Just as land-based wind energy kites fly in figure 8 patterns to accelerate themselves faster than the wind, so does the Dragon underwater. This, says Minesto, lets the Dragon pull more energy from a given tidal current than other designs -- and it also changes the economic equations for relevant sites, making slower tidal flows worth exploiting.

These are by no means small kites -- the Dragon 12 needs to be disassembled to fit in a shipping container. It rocks a monster 12-meter (39-ft) wingspan, and weighs no less than 28 tons. But compared to other offshore power options like wind turbines, it's an absolute minnow, and extremely easy to install using a single smallish boat and a sea bed tether. As with any renewable energy project, the key figure here is LCoE (levelized cost of energy) -- so what's it gonna cost? Well, back in 2017, Minesto projected about US$108/MWh once its first hundred megawatts of capacity are installed -- with costs falling thereafter as low as $54/MWh.

The Dragon 12, like other tidal devices, will be more effective in some places than others -- and Denmark's Faroe Islands, an archipelago in the chilly North Atlantic between Scotland and Iceland, offer ideal conditions. Home to about 55,000 people and more than a million puffins, the Faroe Islands funnel tidal currents through a number of slim channels. This accelerates the water significantly, and thus increases the energy that devices like the Dragon 12 can harvest. That's where the first Dragon has been deployed, and on Friday, it was connected to the local power grid to begin delivering energy.
You can watch a video of the Dragon 12 on YouTube.
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28-Ton, 1.2-Megawatt Tidal Kite Is Now Exporting Power To the Grid

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  • by Anonymous Coward
    Nothing in this world is free. If you harvest energy in this manner, it will be taken from the tidal currents. This, in turn, will hinder the movement of water taking place due to gravitational interactions with the Earth's moon. This will cause the moon's orbit to decay, bringing it closer to Earth, and potentially one day setting it on an unstoppable path to merge back with the main planet's mass, which would cause the certain extinction of all life on Earth. We need to stop doing destructive things i
    • Take your meds.

    • The moon is moving away from Earth as it is stealing rotational energy.

      • True, and it has been doing so for billions of years.
        That means that in the long run we won't have as much tidal energy to harvest, but by then the solar evolution will cook the planet anyway.

        If anything, global warming will take more energy out of the earth-moon system, since the polar ice will melt, and there will be more water to slosh around the oceans,

        • by ShanghaiBill ( 739463 ) on Tuesday February 13, 2024 @04:07AM (#64235932)

          If anything, global warming will take more energy out of the earth-moon system, since the polar ice will melt, and there will be more water to slosh around the oceans,

          The bigger factor is that, as the poles melt, the meltwater spreads out over the oceans, slowing the rotation of the earth, like a ballerina extending her arms will slow her spin.

          The slower rotation means that the tides occur less frequently, and thus the moon is boosted to a higher orbit more slowly.

        • by gweihir ( 88907 )

          I did find a figure that 600M years ago, the day was about 22h long. So if we take a _lot_ of energy out of the system and double the losses (probably would take several orders of magnitude more than the current energy consumption of the human race), we may have a 26h day in 300M years or so. That strikes me as a not very immediate problem.

          • I did find a figure that 600M years ago, the day was about 22h long

            That sounds about right, but its an unclear measurement into a complex and time variable system. The shape of the continent coasts varies with time.

            I checked my reference file, which tells me that the rotational angular momentum of the Earth is about 7.08E+027 kg.m/s. How that relates to human energy use,I dont know. (and my maths may be wrong)

            There are several points in time where the rotation period of the Earth compared to the Moon's or

    • Re:Horrible idea (Score:4, Informative)

      by backslashdot ( 95548 ) on Tuesday February 13, 2024 @03:55AM (#64235902)

      Do you realize that would take a literal billion years? If our species is too daft to have made it off this rock, not to mention figured out other sources of energy we can't blame the universe pressing ctrl-alt-del.

      • We probably have a billion years, but maybe not a lot more. Well definitely cook long before the Sun turns red giant.
    • ... of how a little (or tiny in your case) bit of knowledge is a dangerous thing. I'm guessing you failed physics at school.

      • by tattood ( 855883 )

        ... of how a little (or tiny in your case) bit of knowledge is a dangerous thing. I'm guessing you failed physics at school.

        I'm guessing you failed at humor.

  • by 93 Escort Wagon ( 326346 ) on Tuesday February 13, 2024 @02:19AM (#64235810)

    It doesn't actually show it working. First it shows the Dragon sitting on land, waiting to be deployed; then it shows the ship towing it out to be deployed - there's some pretty scenery, if you want to watch a 2 minute 40 second video to see some snow-covered island.

    The final 5-10 seconds may or may not be camera shots of an operational device - it's hard to tell exactly what's going on.

  • Tidal energy harvesting is tricky. But on the other hand, it is very reliable and predictable. No "Dunkelflaute" to be expected.

    I do expect that some morons will now complain that his will eventually make the Moon crash into Earth. While true, energy harvesting is a tiny part of that even if taken to the max. The losses from the water being moved at all are far, far greater and they will still take a few 100M years to cause any real problems.

    • by vyvepe ( 809573 )

      I do expect that some morons will now complain that his will eventually make the Moon crash into Earth. While true, energy harvesting is a tiny part of that even if taken to the max.

      It is not true. Increasing use of tidal energy slows down Earth rotation and increases Moon orbit until Earth rotation period is the same as Moon orbit period. Increase use of tidal energy results in just the opposite of Moon crashing to Earth.

      • by gweihir ( 88907 )

        Ah, true. I do know how orbital mechanics works, but I always have the wrong intuition for some reason and do not always remember that. Thanks for pointing this out.

        Anyways, if we go really excessive and double the friction losses, we would then have something like a 26h day in 300M years from now. I do not think that is a real concern. No idea how much energy we would need to take, but probably a few orders of magnitude more than we currently use.

  • by Rei ( 128717 ) on Tuesday February 13, 2024 @03:20AM (#64235862) Homepage

    To anyone who speaks Icelandic, the Faroese language is hilarious (and I understand that the inverse is true as well) - close enough that you can generally read the other, but often with radically different meanings. E.g.:

    This ad [gthg.blog.is]:

    Faroese: "Are you a member?"
    Icelandic: ~"Are you a penis?"

    This sign [jensgud.blog.is]:

    Faroese: "The Red Cross"
    Icelandic: "The Angry Cross"

    This drawing [squarespace-cdn.com]:

    Icelandic: "In a room, it's best to lay down on a mattress and cover yourself with a duvet"
    Faroese: "In an outhouse, it's best to lay down on a duvet and cover yourself with a mattress"

    This sign [www.hugi.is]:

    Faroese: "Customers Only"
    Icelandic: ~"Go Away, Businesspeople"

    This notice [gstatic.com]:

    Faroese: "From Sunday, October 15, it is again permitted to use studded tyres. It's possible that some people will be tempted to put on studded tyres before the weekend, but it's not advised to put on studded tyres e.g. on Friday or Saturday, just from Sunday."
    Icelandic: ~"From Sunday, October 15th, it's again permitted to utilize vaginas. It's possible some people will be tempted to put their vaginas up undir the week change, but it's not advisable to put vaginas under e.g. Friday or Saturday, just from Sunday."

    Etc. There's one I was looking for but can't find which was a sign advertising a riding school, but in Icelandic it reads as a "Fucking School" run by "Skúli the Fucker" , offering "cultural fucking" and so forth. Pure gold :) Apparently it's a side effect of the person who laid out Faroese orthography (Venceslaus Ulricus Hammershaimb) being somewhat of a nationalist, and - working with Icelandic independence leader Jón Sigurðsson - made it more closely match Icelandic than Danish. The orthography is reportedly somewhat awkward for use with Faroese, but served the purpose of dealing with the different dialects between the islands. Audibly, Icelandic and Faroese feel further apart - for example, when I first heard Byrta's "Norðlýsið" [youtube.com], I could hardly make out anything, but once they published the lyrics and I could see them in text form, it was a sudden, "Oh, THAT'S what they're saying - I just need to twist these vowels a bit!"

    • by Rei ( 128717 )

      Once when I was tired, I once read through half of a Faroese Wikipedia article before I noticed it was in Faroese ;) In my mind, it was just written in Icelandic by an immigrant with some weird words/spellings and on a non-Icelandic keyboard; I nearly went in and started correcting it before some red flags went off and I checked the URL ;)

  • Could somebody please explain how this thing generates 1.2MW?

    Raccoon Mountain pumping station is enormous and generates just 1.6MW. How did they arrive at the figure of 1.2MW for this thing?

    • Re:1.2 MW? (Score:4, Informative)

      by gweihir ( 88907 ) on Tuesday February 13, 2024 @03:37AM (#64235878)

      Simple: Your number for Raccoon Mountain is off by 3 orders of magnitude.

    • 1.2MW isn't a lot in the scheme of things , its approx 1500hp, ie the power output of a small locomotive.

      As for your racoon mountain (sounds like a Disney series) , according to wikipedia that generates 1.6 GIGAwatts, ie > 1000x more.

      I suggest you fact check first before posting next time.

      • As for your racoon mountain (sounds like a Disney series)

        I assumed it was close to Raccoon City, which has all sorts of other issues.

    • Re:1.2 MW? (Score:5, Informative)

      by Firethorn ( 177587 ) on Tuesday February 13, 2024 @04:54AM (#64235990) Homepage Journal

      1.2MW makes perfect sense - a large wind turbine will be around 1-3MW. Getting closer to 3.5MW.
      The blades can be a lot smaller because water is far more dense than air - more energy by volume.

      Raccoon Mountain is listed as 1.65GW, not MW. [wikipedia.org]

      IE you're looking at over a thousand of these to equal it.

      • by AmiMoJo ( 196126 )

        Large on-shore turbines are over 6MW, large offshore ones are 10-13MW. Prototypes of 16MW turbines have been in operation for a years in China, but not yet into mass production. Rotor diameter on the largest ones is 252m.

  • by robbak ( 775424 ) on Tuesday February 13, 2024 @04:01AM (#64235916) Homepage

    Tidal power has been a challenge because seawater is an unforgiving environment for mechanical things, as well as being very dense and exerting lots of force on everything.

    Simple turbines secured to the sea floor are still beyond our ability to make reliable. With pivoting wings and bearings, I give this thing a few days of operation before it falls apart.

    • by Rei ( 128717 )

      as well as being very dense and exerting lots of force on everything.

      That's generally considered a plus when it comes to power generation...

      With pivoting wings and bearings, I give this thing a few days of operation before it falls apart.

      You have heard of ships before, right?

      • by Kokuyo ( 549451 )

        His point does stand. Ships take much more maintenance than people seem to be aware of.

        However these things seem small enough... and buoyant, so I guess it's feasible to just do maintenance on site.

        We'll have to wait and see if the concept works out.

        • by Firethorn ( 177587 ) on Tuesday February 13, 2024 @04:59AM (#64235994) Homepage Journal

          HIs estimation is off by a couple orders of magnitude though, I wouldn't expect days, but more years before failure. Ships don't normally break down every trip across the oceans, and they don't need huge crews doing constant maintenance anyways, at least, non-military ships don't.

          It's more haul them out like every 5 years or so for major work and cleaning.

          Small might be relative, it's still listed as 24 tons. Small seems to me to be more a factor for moving it elsewhere for maintenance - something heavy is harder to move, so you're more likely to do the work onsite.

          But then, this is a test system, so let it run for a year or three, or until it breaks, then haul it back and assess and measure all the wear so you can redesign and fix the broken stuff and close to broken stuff to be beefier in the next models.

          The water being cold might help as well.

          • Seems like this thing would be relatively easy to service, as well. In the "parked" period when the tide isn't flowing, just pull up a ship with a loading crane on it and you can lift the whole thing onto the deck. If they were smart with the design, the wear/salt-exposed mechanical parts are rebuildable units and they just swap a rebuilt one in and drop it back in the ocean.

          • All the ships I worked on had dedicated maintenance crews that worked 24 hours a day, 7 days a week, in order to stave off the slow destruction of the ocean.

            Whatever they could do on the move, they did. Whatever they needed a stationary ship for, they would have between 8 and 12 hours at port to complete. If you're up early enough on a port day, you can see those cats getting strapped into their harnesses and prepping for the maintenance to be attended to.

            Hell, there were a couple of times a fellow seama

          • There are about thirty years of records of dead tidal power experiments in Scottish waters - specifically, the Pentland Firth. The sea wrecks these machines with what would be contemptuous ease, if the sea had a mind
      • by Viol8 ( 599362 )

        "You have heard of ships before, right?"

        You ever heard of dry docks? Plus a hull + propellor is a lot simpler than this.

        • Most ships need some sort of rudder for steering, which brings ships back up to the complexity level of this thing.

          • by Viol8 ( 599362 )

            Not really. An equivalent to this would be a tug pulling a vessel where occasionally cables snap and/or other things go badly wrong.

            • There's LOTS of cables used at sea, often for decades at a time. I think before making this comparison we should wait until the cable actually snaps.

              Tug boats are a lot more powerful than this thing.

    • A standard engineering rule of thumb is doing anything underwater doubles the cost.

      Doing it in salt water doubles the cost again.

    • It has been mostly achieved in this project from the 60s.

      https://en.wikipedia.org/wiki/... [wikipedia.org]

      • That's about the only way it has worked - roughly standard hydro plant hardware in a dam placed across an estuary. Down horrible things to that estuary's environment, but a new environment develops afterwards

    • I give this thing a few days of operation before it falls apart.

      That's an easy prediction to test. How many days shall we wait? Five? Ten? If it's still working then, will you acknowledge you were mistaken?

  • Both for supposedly weighing 28t and supposedly generating over one MW...

    If this thing does work then I gotta say I'm very impressed.

    • by Barny ( 103770 )

      Seems a bit of a problem, though. I can't imagine this thing wouldn't be a shipping hazard, and 1.2MW (I first thought that was a typo) means seems a bit of a drop in the ocean given that GW are needed.

      Credit where it's due, though, these kinds of things do provide a nice baseline power.

      • by Rei ( 128717 )

        1.2MW (I first thought that was a typo) means seems a bit of a drop in the ocean given that GW are needed.

        Everything needed to supply the needs of 8 billion people is of unfathomably large scale.

        Thankfully, so is the industrial output of 8 billion people in order to make the hardware that supplies said needs.

      • by Kokuyo ( 549451 )

        Well, we're building more than one of those 3MW wind thingamajiggs too, don't we?

      • by necro81 ( 917438 )

        1.2MW (I first thought that was a typo) means seems a bit of a drop in the ocean given that GW are needed

        Well, once you've deployed GW-scale electrical generation without any medium-scale prototypes or field trials, please do let us know. Are you really getting on their case because their first device hasn't already solved a global problem?

      • Agree, I read somewhere recently a datacenter consumers 1MW/sq meter of usage space. Given how fast AI loads are going to add football fields of datacenters, I see a problem.
    • by necro81 ( 917438 )

      supposedly generating over one MW

      My sense of scale is off, because I'm used to picturing wind turbines. A 1-MW wind turbine might have a rotor diameter of 50 m. From the image in the article, the turbine looks to be about 1.5 m, which would give it 1/1100th the swept area as that 50-m wind turbine. But that's OK, because (cold, saline) water is roughly 1000x denser than air.

      A little poking around on google indicates that you can get a 1500-hp [1.1 MW] marine propeller with a diameter comfortably les

  • by Max_W ( 812974 ) on Tuesday February 13, 2024 @04:33AM (#64235960)
    These issues are to be addressed before employing widely.
  • The world consumes about 19 terawatts of electricity per hour, or 19,000,000 megawatts. The world's electricity consumption is growing rapidly, and is expected to reach 26 terawatts by 2030.
    • It's niche. Tidal energy can't offer much on a world scale but it might help some places. Like dams work on other places and wind on others.
      It doesn't have to provide half the world energy in order to have uses. As long as people don't expect silver bullet solutions from it.

  • What size is this? (Score:5, Informative)

    by TonyJohn ( 69266 ) on Tuesday February 13, 2024 @08:30AM (#64236234) Homepage

    The article (and the Minesto website) quotes the wingspan as being 12m, but there are pictures of it surrounded by people which make it look about 6m across. The website says the turbine diameter is 3.5m, but there are women standing next to the turbine who can comfortably see over the top. Perhaps the Swedes are taller than I think...

    I think a lot of the media out there is actually of the Dragon 4.

  • The reason this was deployed to the Faroe islands is that they are remote and energy is already expensive there. Power from this thing costs ~$1/kWh. For reference, California has the most expensive electricity in America at ~$0.29/kWh. Even the rosy future prediction price is more than twice that!

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