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Earth Power

Fusion Energy: the 35-Country Clean-Energy Effort to "Bottle the Sun' (cnn.com) 218

This week CNN published an article chronicling how 35 countries "have come together to try and master nuclear fusion, a process that occurs naturally in the sun — and all stars — but is painfully difficult to replicate on Earth.

"Fusion promises a virtually limitless form of energy that, unlike fossil fuels, emits zero greenhouse gases and, unlike the nuclear fission power used today, produces no long-life radioactive waste. Mastering it could literally save humanity from climate change, a crisis of our own making." If it is mastered, fusion energy will undoubtedly power much of the world. Just 1 gram of fuel as input can create the equivalent of eight tons of oil in fusion power. That's an astonishing yield of 8 million to 1. Atomic experts rarely like to estimate when fusion energy may be widely available, often joking that, no matter when you ask, it's always 30 years away. But for the first time in history, that may actually be true....

The main challenge is sustaining it. The tokamak in the UK — called the Joint European Torus, or JET — held fusion energy for five seconds, but that's simply the longest that machine will go for. Its magnets were made of copper and were built in the 1970s. Any more than five seconds under such heat would cause them to melt. ITER uses newer magnets that can last much longer, and the project aims to produce a 10-fold return on energy, generating 500 megawatts from an input of 50 megawatts.... The dimensions are mind-blowing. The tokamak will ultimately weigh 23,000 tons. That's the combined weight of three Eiffel towers. It will comprise a million components, further differing into no fewer than 10 million smaller parts.

This powerful behemoth will be surrounded by some of the largest magnets ever created. Their staggering size — some of them have diameters of up to 24 meters — means they are are too large to transport and must be assembled on site in a giant hall.... Even the digital design of this enormous machine sits across 3D computer files that take up more than two terabytes of drive space. That's the same amount of space you could save more than 160 million one-page Word documents on. Behind hundreds of workers putting the ITER project together are around 4,500 companies with 15,000 employees from all over the globe... Now commercial businesses are preparing to generate and sell fusion energy, so optimistic they are that this energy of the future could come online by mid-century.

But as ever with nuclear fusion, as one challenge is overcome another seems to crop up. The limited stocks and price of tritium is one, so ITER is trying to produce its own. On that front, the outlook isn't bad. The blanket within the tokamak will be coated with lithium, and as escaped plasma neutrons reach it, they will react with the lithium to create more tritium fuel... First plasma is now expected in 2025, and the first deuterium-tritium experiments are hoped to take place in 2035, though even those are now under review — delayed, in part, by the pandemic and persistent supply chain issues.

"This article has some nice photography," writes Slashdot reader technology_dude. "It really makes it hit home on the incredible amount of design and planning work that is required."

The article notes that when Stephen Hawking was asked which scientific discovery he'd like to see in his lifetime, Hawking answered, "I would like nuclear fusion to become a practical power source."
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Fusion Energy: the 35-Country Clean-Energy Effort to "Bottle the Sun'

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  • by OpenSourced ( 323149 ) on Sunday June 05, 2022 @02:40PM (#62595236) Journal

    4,500 companies with 15,000 employees

    That's 9 times the number of companies in the S&P500, and the employees would fill about the twenty lower rows in a big stadium!

  • That's cute (Score:3, Insightful)

    by Anonymous Coward on Sunday June 05, 2022 @03:02PM (#62595268)

    How long have they been at it? What progress?

    Apparently it was all the hot fusion guys who couldn't stop shouting loudly how they couldn't reproduce the cold fusion guys' results. And somehow they pretty much utterly failed to make all that hot fusion money into fusion, nevermind all that lovely energy they keep promising us with their fusion.

    So far the most direct way to use fusion energy is to use solar panels. Those do seem to get better in a hurry. Curious, no?

    • Re:That's cute (Score:5, Insightful)

      by phantomfive ( 622387 ) on Sunday June 05, 2022 @03:56PM (#62595380) Journal

      And somehow they pretty much utterly failed to make all that hot fusion money into fusion,

      This is nonsense, there are multiple very real ways to make fusion [wikipedia.org]. We know how to do "hot fusion" as you call it.

      The goal now is to make break-even controlled fusion, and then make it cheap.

      • by sfcat ( 872532 )

        The goal now is to make break-even controlled fusion, and then make it cheap.

        Not quite. The heat from a fusion reaction is over 1,000,000 C. To extract energy from heat that high is an unsolved problem (hell, nobody is even working on it). In other power plants we extract energy from heat in the 200-300C range and at 45% efficiency. We can do it up to 3000C (I think, I know we can do up to 1000C). Past that, it is anyone's guess how efficiently we can extract energy. So it isn't Q > 1 we need to reach, it is Q > 1 / .45 or whatever efficiency we can extract energy from 1

        • by Klaxton ( 609696 )

          "To extract energy from heat that high is an unsolved problem"

          They aren't needing to figure out how to tap a million-degree plasma. The harvestable energy, according to what I have read, is in the form of neutrons that escape from the plasma or imploding fuel pellet or whatever is fusing. The neutrons strike something in the enclosure that ideally will get hot and be able to carry the heat away. There appear to be some possible solutions to that, and the problem is not being ignored.

          "It won't happen in any

    • It took a few decades, but NASA is finally catching onto lattice-confinement fusion with some successful papers. https://spectrum.ieee.org/cold... [ieee.org]
  • by Eunomion ( 8640039 ) on Sunday June 05, 2022 @03:02PM (#62595270)
    It will be useful, for sure. Aircraft carriers, submarines, and spacecraft would definitely benefit. But as a general power source, a baroque contraption like a fusion reactor isn't going to catch up with the pace of cost improvement in solar photovoltaics. Every tiny bit of progress has to be clawed forward at high expense, custom design, and complexity, while the PV industry makes geometric cost progress every time electronics improve. And it's the cost curve that matters, not absolute efficiency.
    • by PPH ( 736903 )

      The limiting resource for PV is real estate. Have you checked on the price of that lately?

      • Re: (Score:2, Troll)

        by fahrbot-bot ( 874524 )

        The limiting resource for PV is real estate. Have you checked on the price of that lately?

        And it's only available for about 12 hours/day, when it's sunny. A centralized fusion plant can run 24/7 rain or shine.

        • by beelsebob ( 529313 ) on Sunday June 05, 2022 @03:32PM (#62595330)

          Thatâ(TM)s a solved problem. Even with todayâ(TM)s battery technology, time shifting solar production to demand is cheeper than competing methods of production. The cost of these storage systems (along with the solar arrays too) is rapidly dropping too.

          • That's a solved problem. Even with today's battery technology, time shifting solar production to demand is cheeper than competing methods of production.

            Sure, but generating and storing some of that power 12 h/day isn't the same as generating power 24 h/day.

            • Sure, but generating and storing some of that power 12 h/day isn't the same as generating power 24 h/day.

              With competent transmission, we won’t run out of area to put panels even if we have to use 2x as many panels and storage kWh to get from 12hr average load coverage to 24 hr. Given how solar panel prices keep dropping while efficiency slowly rises, and grid battery storage getting cheaper, it’s not going to take that much longer.

          • We're producing about 1/1000 of the volume of batteries needed to seriously transform into PV+batteries -based energy grid and we're already running into shortages of lithium, cobalt, you name it, pretty much everything. So no, PV+batteries won't seriously solve anything except for allowing the 1% to virtue-signal harder while deriding the masses. Fusion might solve stuff, yes, decades from now and that's a big "might", but that's reason enough to invest in it.

            Also, a citation needed on that "shifting so
        • by u19925 ( 613350 )

          You don't need prime real estate. Maybe not viable in Singapore or Monaco, but most other countries have more than enough space for solar. Exxon owns 15 million acre of land in US alone. You can produce more solar electricity from this land than electricity from all of oil/gas produced by Exxon.

        • by mspohr ( 589790 )

          OMG! I forgot that the sun doesn't shine at night.
          You guys have found the fatal flaw in my plan...
          What could possibly be done? Ever heard of a battery?
          Australia has several very large ones which have saved them millions.

          • Ever heard of a battery?

            Sure, but generating power and saving some of it 12 h/day isn't the same as generating power 24 h/day like a fusion plant could (and maybe even saving some of that). Also, while an outlier case, solar w/batteries doesn't really work in the extreme northern/southern latitudes where there may be several months of near/complete darkness...

            • One problem with nuclear is that it can't follow the load which is much lower at night. Solar, wind and batteries are an ideal mix for 24/7 power.

              • One problem with nuclear is that it can't follow the load which is much lower at night.

                For fission power plants sure (they're most efficient at full capacity), but will that also be true for fusion plants? Perhaps, but for different reasons. Then again, either fission or fusion could be used to charge batteries (or other storage methods) for periods of greater demand -- like using a nuclear power plant with pumped hydro storage -- there's one here in Virginia: Bath County Pumped Storage Station [wikipedia.org].

                • by vivian ( 156520 )

                  If you are using a nuclear heat source it to heat a lot of water with large thermal mass and run a steam turbine just like a coal plant does, then I can't see how it would be any easier to modulate power output than it is for a coal plant. After all, you can put out the fire in a coal plant quickly enough - just cut off the air supply or fuel or flood it with nitrogen, just like you can stop a fusion reaction quickly by cutting off the fuel.

                  Gas turbine output can be moderated more easily because the gas is

                • Re: (Score:2, Interesting)

                  by Anonymous Coward
                  Also not true for several Gen3+ reactor designs - for example, LFTR will load follow just fine. It's a benefit of the whole walk-away-safe design (where doppler scattering prevents the fuel from heating past a certain point). Want more power? Pump more coolant through them. Want less? Reduce coolant flow.
        • by orlanz ( 882574 )

          A centralized fusion plant can run 24/7 rain or shine.

          You know this comes in all the time... and its not really that true. As you shift more and more generation to nuclear, you quickly start approaching the ceiling on how much left over heat you can dump into that local environment. The locations with massive amounts of water needed to take the heat away are more limited in their availability than for many other power sources.

          You don't need much temperature increase to cut down on oxygen for aquatic life. Not much to cause toxic algae blooms.

          • by sfcat ( 872532 )
            If you have multiple ways to use the power, you don't have to dump a lot of it into the environment. Dumping heat into the environment is basically wasting money. You think the owners of power plants want to do that? A really large scale nuclear setup (no matter if you are doing fusion or fission) would have multiple things it would generate (power, fuel, ammonia, hydrogen, and desalinated water). As it switches between them due to load, it might spike the amount of waste heat, but it wouldn't be dumpin
            • Nuclear is probably 40% efficient at best. I would be surprised if any production plant in the US passes 35%. Even with all you say, you may get to 50%. You will always have massive amounts of heat dumped out in a relatively small area.

              You need to maintain a temperature difference to get any work out of it. The work itself only removes 1/3 of the heat and then the diff is closed by 2/3. Rinse, repeat, not only is the diff down, but it's 1/4 the work now and dropping.

              If you don't cool the tail side, you

            • by Klaxton ( 609696 )

              Nuke plants boil water to produce electricity, and a considerable amount of the energy is lost as waste heat. That heat can be evaporated away in which case you use a huge amount of water. Or it can be dumped into the sea or a river, which does heat the local environment.

      • The limiting resource for PV is real estate.

        There's a lot of roofs without PV systems on them. At the end of the day, all that matters is the cost per watt. Fusion may never be an economical source of energy, at least not the kind of fusion that takes place here on Earth. If it's cheaper to point some PVs at the big fusion reactor in the sky, that's what will be done.

        • by orlanz ( 882574 )

          Its funny how many people focus on Fusion and all its marketing utopia of the future. Just do what France does with their nuclear fuel and the US is pretty much set for 3-4 generations. But that's not considered viable (political, economic, etc reasons). However, dismissing alternatives for a pipe dream is OK.

          Please, by all means, continue to fund Fusion... but we can do other things in the meantime too rather than keep shoveling coal.

        • by sfcat ( 872532 )
          Well...perhaps you need to do some more research on the cost of renewables. When you are told that PV is cheaper than say oil, you are being given a capacity cost. Meaning if you built a 1 GW solar PV array it costs less than building a 1GW oil fired (or whatever source) power plant. That oil fired power plant needs to buy oil to fuel it, it can make you power about 60% of the time and the times it is down are predicable and can be adjusted. On the other hand, your solar PV array makes power about 10% o
      • by mspohr ( 589790 )

        Have you checked the price of land out in the middle of nowhere?
        Literally dirt cheap.
        Also, most urban/suburban PV is installed on rooftops... free land.

      • The limiting resource for PV is real estate. Have you checked on the price of that lately?

        That's not even close to being an issue. Out my window in a major metropolitan area are a bunch of 1-story houses with 2-car garages and big lawns, owned by middle-class people. Since nobody around here is named Vanderbilt, and this is neither a rural area nor a giant state, it's pretty obvious that land is not expensive in general.

        But the kind of land used for power infrastructure is dirt-cheap even compared to that, and solar loves desert wastelands.

        • by PPH ( 736903 )

          Out my window in a major metropolitan area are a bunch of 1-story houses

          And that's fine for serving residential loads. But not commercial or industrial needed to support your lifestyle. And residential demand is a small part of overall electrical load. You might think that your PV system takes a big chunk out of your electric bill. But if you figure your grocery store, department store, office building and data center's demand, your rooftop plus theirs don't come close to providing enough area.

          and solar loves desert wasteland

          So do endangered rats. Don't forget the external costs of all that "free" land.

          • I wasn't suggesting that residential zones can support the full needs of the energy economy, just making the point that land in the United States is really not expensive in general. Also, it would take a hilariously small amount of this country's land to fully power it with solar. Certainly far less than it takes to feed cows.

            So do endangered rats. Don't forget the external costs of all that "free" land.

            The external costs are definitely trivial compared to those of any other energy technology. Also, I don't think desert rats object to having more shade, more water condensing in the

    • by u19925 ( 613350 )

      Solar PV and wind will take over majority of the electricity market (at least 80%) in next few decades. There are many utility scale energy storage and long distance transmission lines are being developed which will be able to deliver cheap solar energy to 90% of the population 90% of the time by 2050. Remaining 20% can use hydro, bio-fuel or synthetic fuel produced using chemical reactions from solar/wind electricity.

      Fusion was always under development and it will be still born when delivered.

      • I agree. Solar especially will sneak up on people: Its economic advantages compound over time and are greatly amplified at scale, while each bit of market share taken away from fossil fuels makes their absurdly high hidden costs more and more visible. It also benefits from progress in so many different well-funded industries that it would advance even if literally no one was directly funding R&D for solar panels.

        The issue with fusion is that what sounds like an advantage is actually crippling: If t
    • Even a tokamak based fusion plant design can be cheaper than a solar plant depending on the energy output. Saying nothing about the fact that once the tokamak proves practical investment in developing other cheaper and more compact designs like Dense Plasma Focus, MagLIF, and Polywell will get the investment needed to be developed.

      • Thermodynamics makes that highly unlikely: A solar panel doesn't generate power, it just passively harvests it from a naturally-occurring fusion reactor in the sky. Whereas an artificial fusion reactor internalizes all the cost and complexity of generating the power that it harvests. So the idea that the latter could compete with the former is a little bit like imagining that an internal-combustion car would be cheaper if it was designed to carry a portable oil-drilling rig: It doesn't make any sense in c
    • Economically? When you factor in that this may be the only way for humankind to survive, suddenly the cost/benefit ratio looks very attractive.
      • It will eventually be a survival necessity, but not on Earth. This is a pretty energy-rich environment, and sooner or later we just have to impose hard limits on energy generation to avoid cooking the atmosphere. As for decarbonization, fusion reactors will not come fast enough to replace fossil fuels before the other alternatives have already done so.
    • Aircraft carriers, submarines, and spacecraft would definitely benefit.

      Not unless we can make a much, much smaller and less complex fusion reactor. As the article says the tokamak itself is 23,000 tons without the necessary neutron shielding you would need for any human-occupied vessel which would likely and thousands of tons more. It also has over a million components.

      For comparison, the ISS is ~440 tons and took multiple launches to build. You would need to reduce the mass by at least 2-3 orders of magnitude for it to be practical for spacecraft - probably 3 by the time

      • Those are good points. But I do think applications like carriers, subs, and spacecraft would be in a fusion reactor's evolutionary path, since they tend to be undertaken with indifference to cost and with a pretty insatiable need for high efficiency. Which actually sparks an interesting thought: Maybe the scale of these things would increase precisely to let them have the maximum benefit of a fusion reactor. After all, the scale of a current top-of-the-line aircraft carrier would sound ludicrous and unne
  • If it could cut years off the schedule then why not spend it.
  • Fusion (other than in bombs) has been Real Soon Now for decades. For a long time they were zapping deuterium ice pellets with lasers. Now they're back to playing with tokamaks. There seems to be a fundamental issue in the way or they would have made it work by now.

    ...laura

    • Lots of things were considered real soon now and then seemed like they would take forever .. see flying machines, even video phones. Home "videotelephones" were promised for well over 120 years until the late 1990s when it started being somewhat practical. Reference: https://en.wikipedia.org/wiki/... [wikipedia.org]

      In the 1980s it was a joke that video phones were right around the corner. Same thing with smartwatches. A comic called "Dick Tracy" popularized the idea of a phone-watch in the 1930s and all kinds of gimmick ve

    • Re:Real soon now (Score:5, Informative)

      by phantomfive ( 622387 ) on Sunday June 05, 2022 @03:57PM (#62595388) Journal

      Fusion (other than in bombs) has been Real Soon Now for decades.

      No, it's been making slow progress for decades. Slow progress because it is under-funded.

      • by gweihir ( 88907 )

        Fusion (other than in bombs) has been Real Soon Now for decades.

        No, it's been making slow progress for decades. Slow progress because it is under-funded.

        Indeed. Working fusion would mean some people got a lot less rich selling fossile fuels. Fusion has indeed made steady (slow) progress ans has not hit any wall so far. But with the extreme greed that the fossile industry has, fusion will, at best, be at the end of the measures to fight climate change.

      • Re:Real soon now (Score:4, Interesting)

        by hey! ( 33014 ) on Sunday June 05, 2022 @05:24PM (#62595552) Homepage Journal

        I think it's a matter of perspective. It's not that progress is slow, in fact progress has actually been fast. The problem is the problem itself is extraordinarily difficult, and for that reason we're not really *strictly* funding limited. For example we likely wouldn't get ten years progress in two years by spending 5x as much.

        I think on D-T fusion at least, we may be in a better position to really accelerate progress with funding after ITER starts returning some results. At present there is so much we simply don't know -- e.g. how generate enough electrical power with the plant to run itself. With a large working reactor we can eliminate a lot of ideas that sound promising but would ultimately be dead ends.

      • No, it's been making slow progress for decades. Slow progress because it is under-funded.

        20 years ago (in my early 30's), I was wandering the streets of Amsterdam one night looking for a cool local pub to hang out just outside of the tourist centre area. I stumbled on pub that seemed to have lots of people hanging out in and lingering outside.I made my way in and the only place I could find to grab a seat, which was on a step of some unused stairs leading up. I was pretty close to a group of men in their

  • ITER will be the first to achieve fusion. To much of a big business attitude, cost overruns, ect.

    • ITER will not be the first to achieve fusion because fusion has already been achieved. The first controlled release of fusion power in 1991. Uncontrolled fusion was earlier.

      Seriously, you people need to open a wikipedia page before posting, you are making yourselves look ignorant by posting ignorant things.

      • When I said "first to achieve fusion" I meant first to achieve commercial fusion, or first to achieve breakeven in a tokomak, but I was on my phone and I am lazy. I thought most readers would be able to "get the drift", but there are always those who like to be condescending, so keep up the good (condescending) work

  • That's not all. (Score:5, Interesting)

    by mosb1000 ( 710161 ) <mosb1000@mac.com> on Sunday June 05, 2022 @04:08PM (#62595410)

    People always talk like sustaining a fusion reaction is the all they need to do to make this a practical energy source. But if these reactors cost billions of dollars just to make 1/2 a gigawatt of thermal power, that is not practical. If they need to be completely overhauled every year, that is not practical. So, in reality, sustaining a reaction is only the first step to making something like this work. After you have that working, there is still a ton of development that needs to happen before this could become a practical power source.

    • Re: (Score:2, Insightful)

      by gweihir ( 88907 )

      Indeed. The thing is that most people are stupid and both have no clue what they are talking about and have no clue that they have no clue. Hence statements about how easy all these things are here on /.

  • In any sane design, Tritium is used for research and to ramp things up to Deuterium as fuel, nothing else.

    • Most designs assume tritium will be produced form a Lithium blanket using reaction neutrons. The reaction can still be D-T
    • If you have a fusion reactor then you have a source of neutrons and so tritium is not hard to produce. However, it is nasty stuff to deal with since it diffuses through almost everything like regular hydrogen and, as a gas, can be easily breathed in. If we figure out how to make D-T fusion work then I suspect it will not be long before we move on to something else simply to avoid having to handle tritium not because of its rarity.
  • High energy neutrons cannot be confined by a magnetic field and will damage the structure. How often will it have to be repaired?
    • This is the entire point of z-pinch fusion. The neutron strike carries the thermal energy required to boil water. By pinching the fusion plasma you are using inertia to confine the area that is struck. There's still the chance of secondary collisions which would change the angular trajectory of the neutron. So yes, there would still at some point be a need to replace parts, but would be greatly reduced as, at least in theory, the majority of neutrons are directed at the thermal transfer medium.

  • Just like it always has been for the last 60 odd years

  • High-energy neutrons released in nuclear reactor cause the reactor material to become weak and brittle over time. In a fission reactor, after about 40 years of operation the reactor has been weakened enough that it may require replacement.

    The neutron flux per unit area/time in a D-T fusion reactor is ~100x that of fission. The entire reactor vessel could possibly require replacement every half year or so unless a workaround for this is found. Even if planned/engineered for such as by a replaceable sacrifici

  • by memory_register ( 6248354 ) on Sunday June 05, 2022 @06:15PM (#62595676)
    Why do we not simply deploy small modular fission reactors now, and fusion is a bonus when it happens? Sure, we have to deal with nuclear waste, but that certainly beats the issues caused by continuing to run on fossil fuels until or fusion happens- which seems quite a ways off.
    • by sbszine ( 633428 )
      I would guess because fission has a greater implementation time / cost compared to renewables. Small modular reactors are a great idea but you can't buy them off the shelf. If it were cost effective today companies would be buying politicians and it would be happening. Really, the best move we can make now in terms of nuclear is to stop shutting down existing fission plants and keep them running until fossil fuels are phased out. If there are any recently shut down plants that can be safely and quickly res
    • Deploying something now is difficult when that something doesn't exist. There's currently one running prototype SMR in the world and it's a reactor designed for Soviet nuclear icebreakers. Rolls-Royce is developing SMRs in the UK and their timeline for making significant amounts of power seems to be 2050 (from their website). For the near future, SMRs are going to be tech demos just like fusion plants. It's going to be hard for them to ever compete with renewables on cost.

  • Russia is a founding member of ITER and a major contributor to the gyrotrons and other components. Apart from being so inextricably linked with the construction of ITER, sanctioning Russia will be difficult, given other members including China and India have not condemned the invasion of Ukraine.

    ITER is now in the process of rethinking timelines and budgets. https://sciencebusiness.net/ru... [sciencebusiness.net]

    • There should be no qualms about keeping ITER going full speed ahead:
      the sooner fusion is working, the sooner Russian oil and gas is sidelined forever.
  • If they wanted to simply "bottle the sun" that would be relatively easy. The energy production of the Sun is actually rather low, not much more than your typical compost heap on a cubic meter by cubic meter basis. The difference is that the Sun is really, really, really big, and in a near perfect vacuum bottle.

    To actually get useful energy production out of a fusion reaction, the energy density of the fusion reaction needs to be multiple orders of magnitude higher than in the sun, which means significantly

  • Fusion energy has never worked, and has never even proven feasible to actually provide usable energy. Why wouldn't we use better proven technologies like solar mirrors in orbit, which requires scaling up rather than new physics?

  • It does not. Although deuterium is indeed available in large quantity, fusion also (realistically) requires lithium to breed tritium. The world's supply of lithium is enough to produce the same as the total amount of energy in fission fuel if we use fast breeders.

    Fast breeders have been operational since the 1950s and are basically unused. If the goal is to produce this "virtually limitless" power, we could do so immediately using them.

    In contrast, the first attempt at a fusion reactor was made in 1938, and today in 2022 we still don't have a single working model.

    And yes, that's the same lithium that will have a dramatically greater impact on CO2 if we use it for batteries in cars rather than some ubertech that can be replaced by dozens of other CO2-free concepts, you know, like wind.

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