Fusion power is getting closer
34 points by doener 12 hours ago | 102 comments
  • tromp 11 hours ago |
  • theappsecguy 11 hours ago |
    It’s been getting closer for what, two decades now?
    • croes 11 hours ago |
      Time for Musk to announce fusion powered self driving cars for next sear
      • esskay 11 hours ago |
        Honestly surprised he's not bought/started a company to work on it so he can proudly proclame they've cracked it and it's coming next year on repeat.
      • ChocolateGod 11 hours ago |
        If you mean fusion powered from the sun by the means of solar panels installed on roofs that charge your car, he's already achieved that.

        Far cheaper and more practical.

    • gjsman-1000 11 hours ago |
      > It’s been getting closer for what, two decades now?

      No reason for pointless cynicism, this is also against the guidelines. Fusion power is like childbirth - yelling at 9 months that it has been 9 months, and is therefore never arriving, would be delusional.

      • mort96 11 hours ago |
        Weird analogy but to work with it: if someone has been shouting that they're about to give birth any moment now since the 1950s, forgive me for being a bit skeptical when they say "but no really I mean it this time".
    • zabzonk 11 hours ago |
      since the late 1950s
      • acidburnNSA 11 hours ago |
        Very true. The 1958 Atoms for Peace conference prominently featured big fusion exhibits expecting breakthroughs soon.
    • JumpCrisscross 11 hours ago |
      > It’s been getting closer for what, two decades now?

      This is low effort. Are you arguing we haven’t made material progress in the last twenty years?

      Material science advances in magnets alone should raise your curiosity to not have to wait for a packaged consumer product to notice advancement.

      • wongarsu 11 hours ago |
        Tbf, the title is kind of low effort too. Of course fusion is getting closer. We all know that at least some people are working on it, the default assumption is that they make some progress. This has been the state of fusion for the last couple decades.

        Arguably there has been a time when fusion got further away (compared to predictions) because of reduced interest and funding. But I'd agree that for the last two decades you could print the headline "fusion is getting closer" at any time, and it would always be true.

        Maybe that's just me ranting about how titles have shifted from trying to inform you and distill the essence of a news article to just trying to get you to read the article. It's really a comment on journalism rather than fusion.

        • JumpCrisscross 11 hours ago |
          > We all know that at least some people are working on it, the default assumption is that they make some progress

          This is a terrible assumption when it comes to basic research.

          > that for the last two decades you could print the headline "fusion is getting closer" at any time, and it would always be true

          What are you basing this on?There have been a few discrete steps forward. In between, ideas and experiments.

          > really a comment on journalism rather than fusion

          Can you quote the line from the article that renders the title misleading?

          • wongarsu 10 hours ago |
            > This is a terrible assumption when it comes to basic research.

            Even trying out things that don't work is progress, since it narrows the space of possible solutions. The only ways to really set back progress would be by getting others to believe something that's untrue, for example by faking research.

            You could manage to not advance the field by not publishing a finding and leaving the field. You can slow progress for example by popularizing a path that doesn't lead anywhere, discouraging people from going down the right path, or just reducing popularity or funding of the field. But slowing progress doesn't erase progress. If you do genuine work and at least talk about it with colleagues on a conference that's advancing the field.

            > What are you basing this on?

            The classic graph everyone uses would be 1, which shows consistent progress over ~40 years. It's a bit out of date now, but I assume the trend has held since then.

            > Can you quote the line from the article that renders the title misleading?

            I didn't call it misleading, I called it lazy and uninformative. A (mild) form of clickbait, because it merely hints at information without providing any. My English teacher would have deducted points for that title.

            1: https://www.researchgate.net/figure/Progress-to-Date-in-Achi...

            • JumpCrisscross 10 hours ago |
              > Even trying out things that don't work is progress, since it narrows the space of possible solutions

              Maybe, maybe not. You may be searching an infinite domain, or the wrong domain entirely.

              > If you do genuine work and at least talk about it with colleagues on a conference that's advancing the field

              Sure. But it’s not advancing a technology.

              > classic graph everyone uses would be 1, which shows consistent progress over ~40 years

              Fair enough. I’d argue that’s constant progress in one of the problems of fusion power, namely, ignition. The article’s point is the other problems are either being solved or showing similar progress. That wasn’t true until recently.

              > it merely hints at information without providing any

              It's debunking the assumption at the top of this thread. Especially with the "no really," it's arguing that the ground truth has changed.

    • adastra22 10 hours ago |
      It’s been 30 years away for half a century. Then it was 20 years away for the last few decades. Now it is 10 years away. We’re making progress!
  • leephillips 11 hours ago |
    • ikrenji 11 hours ago |
      fusion is the ultimate clean energy source. we shouldn't give up on it just because it's a difficult problem
    • stuart73547373 11 hours ago |
      looks like that article didn't read this article https://news.ycombinator.com/item?id=42221756
      • kiba 11 hours ago |
        2 billion dollars over 5 years? That's peanuts! If anything I would increase spending to a billion dollars a year. Would still dedicate most of the budget to accelerating the energy transition, which is trillion of dollars worth of stuff.
  • TheMagicHorsey 11 hours ago |
    It's always been close. But now, finally, I think it's really close. As in, I think I may still be alive when the first fusion power comes into the grid, even if I probably won't be alive to see the full dream of infinite cheap energy come true.

    Its interesting to think about how our economies will change if the price of energy drops by one or two orders of magnitude.

    Desalination could then be used for agriculture and industry. Coastlines could become more valuable.

    We could make huge amounts of aluminum for almost nothing. We'd probably end up with aluminum packaging for everything as it's much easier to recycle than plastic if you don't have to worry about electricity.

    • ahoka 11 hours ago |
      Probably we will just burn the world with the free energy.
      • yawpitch 11 hours ago |
        Probably? Oh ye of little faith.
      • afh1 11 hours ago |
        Even if that was literally done, it would still be a better home than Mars :) https://www.youtube.com/watch?v=5GjOuqAlFEk#t=6m45s

        (not trying to make any kind of point, just a fun fact / video)

        • adastra22 10 hours ago |
          That video is full of widely discredited claims.
    • Anarch157a 11 hours ago |
      > won't be alive to see the full dream of infinite cheap energy come true.

      You won't. Sorry for being cynical, but the true cost of energy is the capital invested in the equipment to harvest it. A fusion reactor would be at the minimum, as expensive as a fission one, which means all that capital will have to be amortised over the years. This doesn't even take into account the cost of extracting deuterium from sea water or producing helium 3 and tritium from lithium. Fusion doesn't even solve the problem of nuclear waste, since it will create radioactive isotopes by bombarding components of the reactor with neutrons.

      You want cheaper, cleaner energy ? Solar and wind with battery storage is the best option, and it's already here, no need need to wait for fusion magic that may or may not happen in our lifetimes.

      • adastra22 10 hours ago |
        > A fusion reactor would be at the minimum, as expensive as a fission one

        What are you basing that on? Many of the fusion designs being talked about are quite small.

        • Anarch157a 10 hours ago |
          So does fission reactors. Modern French nuclear subs are powered by 48 MW reactors. They're still expensive to build and maintain.
    • dale_glass 11 hours ago |
      I don't see why would it be cheap.

      Nuclear is mostly capital costs, not the fuel. Fusion doesn't look any cheaper to build. Like any other bit of complicated infrastructure, it'll have a limited lifetime.

      So, power cost is ((capital_costs + running_costs) / amount_produced) * profit_margin

      While I'm very much in favor of research, I don't understand the expectation of that it'll make power cheap. I'm pretty sure nothing will beat solar and wind because they're cheap, simple and very amenable to mass production in ways that fusion and fission can never be.

      At this point IMO neither fusion nor fission have a future as a main source of grid power. They're still worth researching, and will still have specialized uses in places like submarines and aircraft carriers.

      • energy123 10 hours ago |
        Helion says they want to make small, modular plants that are amenable to mass production, opening up the same scale economies that have benefited solar.
        • dale_glass 10 hours ago |
          That's assuming their stuff even works at all, which I believe there's some reasons to doubt. Perhaps all we'll get working in the end is a honking huge tokamak and then we're exactly in the same situation as fission.

          But let's suppose their stuff works as well as they imagine. IMO, not even then. Just look at their youtube videos. All sorts of big, complicated, and expensive looking magic. Huge capacitors, vacuum chambers, extremely high temperatures, etc.

          Will that scale better than nuclear? Maybe. Will it scale better than a tech that can be pumped out by the million, shipped to normal people and put on any random roof? Highly doubt it.

      • pjerem 10 hours ago |
        To my understanding, the time limit of fission is mostly due to political/security reasons.

        Of course keeping it indefinitely on will require huge maintenance costs but if the infrastructure is modular enough to be able to replace every elements, that may be doable.

        With fission the structure of the building is part of the infrastructure’s security so it’s harder to change when it’s too damaged. Maybe I’m wrong but it seems like fusion doesn’t require huge cement walls that would take a lot of constraint and which would effectively limit the maximum lifetime of the building.

    • Asraelite 11 hours ago |
      > Desalination could then be used for agriculture and industry

      This is likely going to happen anyway because of the rapidly falling costs of solar power. Although it certainly doesn't hurt to make energy cheaper yet again.

    • RivieraKid 10 hours ago |
      Lots of people assume that fusion energy will be cheap but this is not true for the tokamak designs, which have the highest chance of success. Helion's approach should be very cost-competitive but it has a high chance of failure.
    • alwa 10 hours ago |
      What has changed to make you think it’s finally really close now? I found the short article a little light on details, although as a layman I have noticed people seeming cautiously excited about ITER and speaking about SPARC as if its near-term promises may be credible.

      Are there other signals that you’d point to as influencing your shift to optimism?

      • adastra22 10 hours ago |
        There is a massive amount of investment into fusion startups right now, so much that it is difficult to keep track of all the really innovative approaches that are being tried, often with billions of $$$ backing them.
  • zabzonk 11 hours ago |
    "no really" is about right. even if you have managed to produce sustainable fusion with a good bit of output energy (a very big if), you still have the problem of producing useable electricity from it, which as I understand it is one of the things that ITER was supposed to prototype.
    • thrw42A8N 11 hours ago |
      Steam.

      The actual problem is reaction vessel wall ablation.

      • mitthrowaway2 11 hours ago |
        This is one of the reasons General Fusion, mentioned in the article, uses a liquid metal reaction vessel, spinning to create a cavity. (I think a mixture of molten lead and lithium?)
        • thrw42A8N 11 hours ago |
          Yes, incredible idea. I really hope it works out.
      • bryanlarsen 10 hours ago |
        Steam is uneconomical versus solar power. If all the fusion is doing is heating water it will always lose on cost even if the fusion was free.

        c.f. coal. The bulk of the cost of a coal power plant is the steam turbine etc. And coal is not economical.

        • thrw42A8N 10 hours ago |
          My city has a steam/hot water distribution network. No need to convert to electricity for quite a lot of residential energy usage.
    • Thegn 11 hours ago |
      Well, we could always just set up solar panels and use it to capture output from the massive fusion reaction 8.5 light minutes away from us. Does that count as a successful utilization of fusion?
      • JumpCrisscross 11 hours ago |
        > Does that count as a successful utilization of fusion?

        In the way a fire is a steam engine.

  • yawpitch 11 hours ago |
    Fusion power has been getting closer — no really — for a long time.

    Now, don’t get me wrong, I’ll be ecstatic when / if it arrives, especially if it does so with sufficient lead time to be relevant within my lifetime, but no number of “we’ve halved the distance to the wall again” articles will get me excited (or us there).

    • hiddencost 11 hours ago |
      A comparison to Zeno's paradox isn't quite apt, because fusion power can (in this metaphor) go very far beyond the wall.

      I think it's better to think of it this way: are you a lay person not in the field? Then most of this work doesn't matter to you. But you should keep funding it.

      • yawpitch 9 hours ago |
        The wall, in this case, is power positive sustained (and contained) reaction. Fusion power doesn’t exist and can’t do a damned thing until that wall is reached. Once it’s reached I’ll admit we’ve no practical idea where the next wall is going to be.

        And yes, absolutely, fund baby fund, keep making those Zeno steps… just don’t write another article promising me that fusion / Jetson cars / AGI / Unobtanium is nearly here.

        • JumpCrisscross 8 hours ago |
          > power positive sustained (and contained) reaction. Fusion power doesn’t exist and can’t do a damned thing until that wall is reached

          Did we read the same article? Helion's entire design strategy is to sidestep sustaining fusion plasmas. It's unclear if it will work. But it's theoretically sound. Your wall is a chain-link fence.

  • thrance 11 hours ago |
    Comparing the very optimistic deadline given by Commonwealth Fusion, concerning a prototype that has not even began construction versus the latest postponing of the first firing of ITER is kind of meaningless.

    As underlined in the article, ITER is already 9 years behind schedule. Not because they're incompetent or underfunded, but because fusion is hard. I don't expect a private company with much less funding to do any better.

    That said, I'd like to be wrong and see one of these companies crack commercial fusion in their basement.

    • moomin 11 hours ago |
      The Economist always phrases articles to imply that private investment is a magical elixir that will make problems go away.
    • IanCal 11 hours ago |
      The fundamental thing behind SPARC is (iiuc) to do this far faster by being drastically smaller. Iter was designed a long time ago based on materials available at the time. SPARC can be much smaller with much stronger magnets.

      The argument from SPARC wasn't that iter was incompetent but that being so vast and expensive requires multiple nation states cooperating which is inherently slow. Slow things being more risks as thing a change too (9 years is probably 3 governments here). Making it smaller makes it cheaper, a d cheaper means a smaller collaboration (or single company).

  • baq 11 hours ago |
    imagine if fusion research could consistently get 1% of the pentagon's accounting hole.
    • gjsman-1000 11 hours ago |
      That would solve about ~40% of global climate emissions, and would single-handedly do serious damage to politician's attempt to use climate change as a cattle prod.

      Watch them say, "Yay, we've solved climate change" with gritted teeth as they figure out the next useful crisis.

    • YZF 11 hours ago |
      It'd get nowhere. The problem isn't money. One could say there's even too much money thrown at fusion research that could have better use elsewhere. There are just too many incredibly hard problems to solve.
    • esskay 10 hours ago |
      As nice as that would be, if we think about it logically it's not at all in the US governments interests for Fusion to work. Suddenly that massive pot of money from natural resources (e.g Oil) vanishes.
      • alwa 10 hours ago |
        …vanishes, presumably, because the work that it used to do is now done by this fusion technology instead. Surely the US would like to be the nation to dominate that tech should the moment come, right?

        Could sure shake up some of the US’ geopolitical relationships, in which the US spends an awful lot to maintain influence over the way oil gets made and sold. That pot of oil money sure creates its share of headaches, and probably means a lot more to smaller nations than it does to the US.

        • esskay 10 hours ago |
          I guess the question would be that assuming the US was to dominate the technology, is that more profitable than a steady stream of revenue from oil exports?

          Building fusion plants would be a massive money maker initially as everyone races to adopt it, but is it a long term money maker when no doubt other nations will be trying to cash in on it themselves.

          • adastra22 10 hours ago |
            The US doesn’t have nationalized oil companies. The US government doesn’t have skin in the game here. In fact, fusion would make a lot of military stuff cheaper, so if anything they have incentive to adopt it.
            • JumpCrisscross 10 hours ago |
              > US government doesn’t have skin in the game here

              It absolutely does, just in the opposite direction from OP’s hypothesis. Washington likes cheap oil. It wants high production levels from its producers to keep prices low; producers want high and stable prices.

  • znpy 11 hours ago |
    lovely, we only need warp drive now :)
    • alganet 10 hours ago |
      If we're talking Star Trek humanity cosplay, our best bet would be to sort out communicators first. We're almost there. It already works reliably, just needs to be made to respect privacy and be completely free.
  • AtlasBarfed 11 hours ago |
    The Economist as scientific harbinger of the fuuuuture!

    Even if good net-energy happens, even if they solve neutron flux irradiating the reactor vessel, even if they can sustain power generation for commercial periods, if they can safely operate the superhot plasma

    ... it comes down to, ECONOMIST, the cost. As someone that hammers fission power for being currently infeasibly expensive, fusion has a long road to economic viability. I suppose the public will at least not NIMBY it to the same degree as a fission reactor

  • bastloing 11 hours ago |
    But fusion doesn't produce any waste does it?
    • Permik 11 hours ago |
      Technically the helium produced is the waste product, but fortunately we have tons of uses for helium.
    • jvanderbot 11 hours ago |
      It doesn't have reaction byproducts, if you don't count the reactor itself, which gets lots of neutrino bombardment and ends up glowing scrap metal.
      • JumpCrisscross 8 hours ago |
        > which gets lots of neutrino bombardment and ends up glowing scrap metal

        One, neutron. Two, doesn't glow. Three, aneutronic fusion is real.

    • amluto 10 hours ago |
      The actual intended products of the fusion reactions are generally not radioactive and are rather harmless. But most proposed fusion reactions produce neutrons. Neutrons, unfortunately, can hit other nuclei and “activate” them, transmuting them into other isotopes that can be quite nasty. So fusion is far from perfect.
  • acidburnNSA 11 hours ago |
    I'm happy to see lots of investment in fusion. As a fission guy, I know that plenty of challenges remain even after you get your first net energy out, such as getting it out economically. In fission, there were more than 20 years between these milestones (first chain reaction in 1942 from CP-1, first competitive power in 1965 from Oyster Creek).

    As such, some skepticism in people's timelines is always warranted. I'm reminded of the voodoo fusion article. https://vixra.org/pdf/1812.0382v1.pdf

    • readthenotes1 8 hours ago |
      I have a relative who commented one time about how in 1960 year the fusion power was only 10 years away.

      I'm pretty sure he was talking about sustainable electric grid usable power. He spent some time with a key in an underground silo though...

  • gandalfian 11 hours ago |
  • pjerem 11 hours ago |
    Fusion is cool and all but it will not save us from anything. We already have enough tech to make emission free and cheap electricity.

    "All" we need is political action to build more clean power plants (nuclear, solar …) and continuation of research to electrify more sectors.

    Fusion will not solve any of those important issues. It will only be the cherry on the cake if it become deployed globally anytime in the future. But we are far from it and we shouldn’t be that excited or hope for it to make a better world.

    I very much see fusion as going to the moon : it’s not going to solve any short time issue but it can be a milestone in human advancement if we manage to survive until it becomes our primary source of energy.

    • JumpCrisscross 10 hours ago |
      > "All" we need is political action to build more clean power plants

      We’re building solar about as quickly as we can, and without cannibalising EV battery supply chains are also maxed out on batteries. Fission power remains uncompetitive with natural gas; you’d have to convince Western consumers to bear higher prices for reduced emissions which nobody is willing to do.

      • catskull 10 hours ago |
        Exactly this. If we drop the cost per kWh by half, the market will respond. The market doesn’t ultimately care about the planet which is why we need govt but bringing the price per kWh with clean fusion kills two birds with one stone.
        • pjerem 10 hours ago |
          That’s why I talk about political action. Public is exactly here to act when the market doesn’t care about something important.
          • JumpCrisscross 10 hours ago |
            > why I talk about political action. Public is exactly here to act when the market doesn’t care about something important

            Which is why I mentioned consumers. Voters have made this incredibly clear every time polled: we are not wiling to pay more to reduce emissions.

            • PaulDavisThe1st 10 hours ago |
              Can you mention a recent time they were polled and make this incredibly clear?
              • snapplebobapple 9 hours ago |
                Right now in Canada the libs are just one no confidence vote away from irrelevance, at least partly because of the carbon tax. It's not a direct poll though, as the liberal politicians are basically the junkest junk that party has ever gotten elected and all the corrupt and/or stupid things they have been up to are all coming to light at once. The carbon tax isn't helping them but it is unclear if it's the major problem for the voters or just one of the very large basket of problems that are becoming obvious.
                • PaulDavisThe1st 8 hours ago |
                  > It's not a direct poll though

                  That's putting it mildly.

              • lenkite 8 hours ago |
                “We will frack, frack, frack and drill, baby, drill,” Trump said in Detroit on Oct. 18. “I will cut your energy prices in half within 12 months. … Cut them in half within 12 months of taking office. That’s going to bring everything down.”
                • PaulDavisThe1st 8 hours ago |
                  Ah, so "polling" means "their attitude towards a political candidate who voices a wide range of policy positions, which it may not be reasonable to assume uniform agreement with" ?

                  This approach to "polling" also appears to ignore the fact that statistically speaking, almost half "the population" made the opposite choice. This makes sweeping statements about "what people want" based on this sort of thing pretty suspect.

                  Of course, the claim could be true, nevertheless. This sort of "evidence" isn't really very salient, however.

              • JumpCrisscross 8 hours ago |
                > Can you mention a recent time they were polled and make this incredibly clear?

                2018 in America, "57 percent of Americans are willing to pay a $1 monthly fee; 23 percent are willing to pay a monthly fee of $40" [1]. 2018 in France, "carbon taxes on petrol and diesel" prompt les gilets jaunes [2]. 2024 in America, "more than half of Americans are unwilling to pay any amount of money to combat climate change" [3].

                And then there is the global success of climate-skeptic or outright denialist citing the cost of Paris Agreement compliance.

                [1] https://apnorc.org/projects/is-the-public-willing-to-pay-to-...

                [2] https://edition.cnn.com/2018/12/31/opinions/macron-warning-c...

                [3] https://epic.uchicago.edu/insights/2024-poll-americans-views...

                • PaulDavisThe1st 7 hours ago |
                  Not that I like or agree with the data, but thanks for providing some.

                  I do recall one of the catchphrases that surfaced around les gilets jaunes: "these people are going on about the end of the world while we're just trying to make it to the end of the month".

                  It's too bad that doesn't prompt deeper reflection about and anger at just who benefits from such a bifurcation of interest.

      • skulk 10 hours ago |
        How do I square this with claims that the US heavily subsidizes fossil fuels? Are those claims false or am I misunderstanding how the market works?
        • JumpCrisscross 10 hours ago |
          > How do I square this with claims that the US heavily subsidizes fossil fuels?

          By noting it’s irrelevant. Solar production isn’t capital constrained. Certainly not in the West.

          • skulk 6 hours ago |
            > Fission power remains uncompetitive with natural gas; you’d have to convince Western consumers to bear higher prices for reduced emissions which nobody is willing to do.

            I was mainly reacting to this. Can nuclear really not compete with gas even if the government subsidized both equally? (with all the caveats that come with comparing subsidies)

            • moomin 4 hours ago |
              I have no idea whether fission plants are competitive with gas plants, and knowing a bit about multi-decade projects, I suspect no-one does. It’s all guesswork.

              What I do know is fission has a horrible cost profile. First there’s a huge build cost, which can often skyrocket unpredictably. Then you’ve got a hugely profitable part where you’re basically printing money. Then there’s an enormous cost at the end.

              Huge cleanup costs, whether it’s nuclear or coal, basically means either government has its eye on the ball to an excellent extent (Australia seems to be good here.) or it’s not going to be fixed except by the same government that didn’t tie down the guys who made the money enough.

              I’d call fission a bad choice for countries with weak or chaotic government. You need a rock solid civil service to allow it.

              (You’ll observe the same is true of almost every mineral extraction project.)

        • nradov 9 hours ago |
          That really depends on what you count as a subsidy. The federal government isn't really making direct payments to fossil fuel companies. Some of them are allowed to lease federal lands at what might be considered below-market prices. The US military helps to provide free security for some oil exporting countries. Fossil fuel producers and customers are allowed to emit pollutants without paying for cleanup or remediation costs. Are those subsidies? Depends on your perspective.
    • HDThoreaun 10 hours ago |
      Fission just isn't a competitive source of energy economically. Nobody is willing to pay 10x as much for energy just to get nuclear. Seems clear to me that the actual solution we need are cheap batteries so we can scale renewables
      • JackSlateur 7 hours ago |
        This is funny

        Here in France, most of our power is from nuclear. This gets us really cheap power production, compared to our neighbors in Europe.

    • jsbisviewtiful 10 hours ago |
      > We already have enough tech to make emission free and cheap electricity.

      As much as I am a proponent of green energy, this claim is outlandish. If we had started building more nuclear reactors 10 years ago, sure, but by themselves wind and solar aren’t quite sufficient enough for places like the US to fully replace fossil fuels. There are limitations for both, namely the need for space and acceptable weather conditions. Solar panel energy yield still has potential to unlock, as well. Last update I’d seen about panels said they still only hover around 25% energy yield.

  • gmuslera 10 hours ago |
    It is getting late to the party.

    Clean enough energy alternatives are being deployed everywhere.

    And we might be already running out of time, the climate system could had surpassed a point of no return by now, we keep adding fossil carbon to the system and if, or by when, this became practical enough to start deploying power plants based on it will be too late for a meaningful change.

  • jbotz 10 hours ago |
    Fusion is irrelevant as a practical energy source here on earth. The simple reason is that we already have all the "fusion energy" we'll ever need from that big fusion reactor in the sky... modern photovoltaics convert this energy to electricity at close to the same efficiency that you could convert the heat from a controlled fusion reactor to electricity. OK, yeah, photovoltaics still don't work at night, but there's a battery revolution underway that is solving that problem, and the two, photovoltaics + batteries, are already vastly cheaper than fusion can ever hope to be.

    Fusion will be important for the future of humanity, especially in deep space, so we should keep researching and developing it. But it's not relevant to the climate crisis... the already existing technologies have that covered, we only need to deploy them faster.

    • steelbrain 10 hours ago |
      While I admire your optimism, this is not realistic. The earth is big and not all parts get the same amount or intensity of sunlight. Nordic countries cannot rely on Solar with batteries, for example.
    • JumpCrisscross 10 hours ago |
      > it's not relevant to the climate crisis... the already existing technologies have that covered, we only need to deploy them faster

      Going all in on solar and batteries either requires nuclear energy, thereby raising power costs, or natural gas, which means we can’t make our 2050 goals. We simply can’t manufacture the panels and batteries fast enough, the latter especially if we also want to decarbonise transportation.

      Fusion won’t come fast enough for the climate crisis. But it may be relevant for complete decarbonisation, e.g. replacing the natural gas plants we’re spinning up as quickly as we’re deploying solar.

    • CELLOPHANET 10 hours ago |
      No, b/c we really need it as a weapon. Fusion lasers will finally provide the death ray of sci-fi. If you think "practical energy source" is what fusion research is really about then you've been bamboozled.
  • johnea 8 hours ago |
    Wouldn't it be awesome if there was a giant free fussion reactor!

    Close enough to get the energy, but far enough away to allow isolation of the reaction.

    Maybe the energy could just beam down on us from space?

    That'd be awesome...

  • joak 8 hours ago |
    I think comments are missing the point: one of the companies listed in article, Helion, is about to switch on a machine to demo net electricity production from fusion.

    Why would that be possible? Because they don't go on yet another fancy way to boil water to run a steam engine. They do direct energy conversion.

    In a fusion reaction energy is mostly released as kinetic energy of particles. Their fusion reaction is aneutronic, ie with few neutrons. That means that the energy is released as movement of charged particles. By definition this is an electric current.

    This current is directly captured by induction in the coils and sent to grid.

    If their 2025 experiments go well, in 2028 they will start selling electricity to Microsoft which whom they have a power purchase agreement.

    Thanks to the simplicity of their machine, they aim at a cost of 10$/MWh, competitive with solar. Their 50MW generator is shipping container size and be built in a factory by the dozens.

    Ok, they may fail, they could also succeed though. Worth watching.

    • orwin 5 hours ago |
      Ah, so it's not charged plate conversion (which seems impossible with pulsed plasma if the plate spacing is too high). Hopefully it works, because I'm _not_ reading another 40 page study/whitepaper on direct energy conversion.
  • orwin 8 hours ago |
    Creating a plasma isn't hard, keeping it is: containment and breeding will be expensive. And absorbing electricity from it will be too.

    Charged plate conversion system require the plate spacing be lower than the Debye radius of the plasma. So it's out for most tech (especially pulsed fusion)

    And a lead-lithium blancket (the only mature tech to capture neutrons rn) is unwieldly, only capture neutrons (so already between 20 and 25% losses, let's say 20), and will loose more energy via reaction (creating deuterium-tritium, so not useless, but still, lost energy, 25% losses). Then between the heat exchangers and the steam engine, let's say 65% losses (and i think i'm generous). So you'll get at best 21% of the generated energy as electricity (and i'm being _Very_ generous. imho if you have more than 15% it's a success).

    With that, you'll have to contain and breed the plasma. Good luck.

  • more_corn an hour ago |
    Still only twenty years away. As it has been for the last forty.