[HN Gopher] General Fusion to build demonstration plant in UK
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General Fusion to build demonstration plant in UK
Author : hanoz
Score : 107 points
Date : 2021-06-17 14:33 UTC (8 hours ago)
(HTM) web link (www.bbc.co.uk)
(TXT) w3m dump (www.bbc.co.uk)
| nix23 wrote:
| I already know how that story continues:
|
| https://www.amazon.com/Paradox-Eternity-Phillip-P-Peterson/d...
| hannob wrote:
| The important sentence: "It won't generate power".
|
| It's all fine to do this as a research project. But this is not a
| technology that is going to solve our energy problems any time
| soon - and it certainly shouldn't distract from deploying the
| solutions that exist today, aka mostly wind+solar.
| Element_ wrote:
| I don't know why it is prefixed with "Bezos Backed", Bezos VC is
| just one of 10 big investors in the company.
| lonelyasacloud wrote:
| How many of the other backers are as widely known and regarded
| for their technical foresight as Bezos?
| pelasaco wrote:
| for clickbaiting.
| RandallBrown wrote:
| Because Jeff Bezos is one of the richest people in the world
| and he has essentially unlimited money.
| Guest42 wrote:
| To me it seems like an unfortunate but common tactic in
| marketing-land to seek out any sort of affiliation with a well
| known brand and to publish it as much as possible.
| rock_hard wrote:
| It's actually the media outlets who do this because it
| generates more traffic for the article
|
| It's why they will also throw in other large brand names and
| stock tickers of entities that could be of the slightest
| relevance
|
| A large chunk of media traffic comes from Google alerts for
| large brands...so the writers try to game the system here
| gentleman11 wrote:
| I read that fusion is safer than fission because it emits less
| particles and is harder to cause a 10k year meltdown. Is that
| accurate?
| Kirby64 wrote:
| Fusion byproducts are by and large significantly safer than
| fission.
|
| Fission byproducts are well known to just be a ton of heavy
| metal junk that decays over thousands of years.
|
| I'm sure there's fusion byproducts that are nasty too, but
| fundamentally you can't get byproducts as high up on the
| elemental chart as you can with fission strictly because fusion
| is merging 2 smaller atoms into 1 larger atom. With fission you
| start with a larger atom and break it into 2 smaller ones.
| Oversimplified, but you get the idea.
| StreamBright wrote:
| This is the 1990's view on the subject. There were several
| projects to address the fission leftover problem. Some of
| these:
|
| - Method to Reduce Long-lived Fission Products by Nuclear
| Transmutations with Fast Spectrum Reactors
| https://www.nature.com/articles/s41598-017-14319-7
|
| - Fast-neutron reactor https://en.wikipedia.org/wiki/Fast-
| neutron_reactor
|
| - Evolution of transuranium isotopic composition in power
| reactors and innovative nuclear systems for transmutation
| https://inspirehep.net/literature/1243003
|
| And few other things. It is possible to have nuclear power
| with shorter byproducts than thousands of years.
| Kirby64 wrote:
| Given that the US has only 1 reactor that was commercially
| put into operation after 1990s [1], it's a pretty realistic
| way to look at it in the US.
|
| Newer reactors and spent fuel reprocessing are definitely
| ways to solve the issue, but the fact is you still create
| those nasty byproducts in the traditional reactors today.
|
| [1]: https://en.wikipedia.org/wiki/Nuclear_power_in_the_Uni
| ted_St...
| Symmetry wrote:
| Basically yes. Both fission reactors and fusion reactors
| generate a bunch of neutrons.
|
| With a fission reactor you have to expose uranium to those
| neutrons and when it gets hit it either splits into dangerously
| radioactive components or absorbs a neutron and becomes
| dangerously radioactive plutonium. There are pipes and stuff
| that become a bit radioactive too but that's not the part that
| people are afraid of when an accident happens. Also, the
| dangerously radioactive byproducts continue to release a lot of
| energy after the chain reaction is shut down, about 10% of the
| power the reactor was run at. So even after a fission reactor
| is shut down you need to keep cooling it otherwise things melt
| and people become unhappy.
|
| With fusion you do need to keep exposing lithium to the
| neutrons from the reaction to make more tritium fuel. And
| tritium is radioactive. But if it escapes it'll go straight up
| into the upper atmosphere where it won't particularly bother
| people and then dilute. You've still got the radioactive pipes
| problem you do with fission but, again, that's not really the
| part that people are afraid of. And once you stop containing
| the plasma energy generation stops instantly.
|
| I'm generally inclined to say that the risks involved in
| fission are worth the benefits but those risks are worth taking
| seriously and require careful government regulation more so
| than other forms of power. With fusion, on the other hand, I'd
| a lot less concerned with someone building a power plant up
| wind of me than a coal plant even with similar levels of
| regulation. Just as long as they aren't deliberately exposing
| uranium to the neutrons or something like that.
| jlos wrote:
| Fission is a chain reaction, Fusion is not. A fusion reaction
| is so unstable that if the reactor failed the conditions for
| sustaining fusion would immediately stop.
|
| It's basically the hottest plasma we can make suspended in a
| magnetic donut surrounding by near absolute zero temperatures.
|
| https://en.m.wikipedia.org/wiki/Tokamak
| FridayoLeary wrote:
| Which is infinitely better then rapidly overheating and
| vaporizing and melting the reactor housing and spreading
| radiation which will stay dangerous for 200 years.
| gentleman11 wrote:
| I had assumed both were chain reactions due to stars. That's
| interesting
| choeger wrote:
| Well, technically, that's right. Fusion _is_ a chain
| reaction. (albeit, "chain" might be a stretch here. Let's
| say it is a continuous process in stars.) But it's driven
| by gravity, not neutrons. You just need to bring about 70
| times the mass of Jupiter into one place and that's it.
| Child's play, essentially ;).
| guscost wrote:
| The enormous pressure inside stars is what sustains the
| reaction. Neutrons coming off a fusion reaction, even if
| moderated, can't really "squeeze together" other particles
| in any sense.
|
| Also, per unit volume, the sun produces about as much power
| as a compost pile.
| only_as_i_fall wrote:
| Does the volume of the sun include its Corona in that
| last statement?
| ben_w wrote:
| That's just the core. Go out to the photosphere, let
| alone the corona, and it's about about a thousand times
| less, 0.27 W/m^3: https://www.wolframalpha.com/input/?i=%
| 28solar+luminosity+%2...
| 317070 wrote:
| No, iirc that statement is for the part of the sun where
| fusion actually happens. Per volume, not a lot fusions
| happen in the plasma on the sun. The crux is that the
| volume of the compost heap grows order cubed to the
| radius, while the area through which the heat escapes
| grows quadratic. And the sun is like, a _really_ big
| compost heap.
|
| In fusion on earth, we want to be considerably more
| efficient than the fusion process in the sun, as we don't
| have as much space to work with. ITER is already a pretty
| big machine.
| innot wrote:
| This lead me to the following - what if you make a
| compost pile the size (mass) of Sun? Meaning, it won't be
| made of hydrogen, but rather some carbon-based molecules.
| I'm not sure about other atoms in these molecules, but I
| think carbon is stable enough not to initiate nuclear
| reactions. So probably fusion won't start. What then?
| shadofx wrote:
| Carbon is capable of fusion, in a sufficiently compressed
| stellar mass. Everything up to Iron-56 can theoretically
| sustain fusion.
| thinkcontext wrote:
| Gravity would compress it. Depending on the exact
| composition fusion could start, ie it would become a
| star. According to Wikipedia carbon fusion requires a
| mass of 8 suns to start but there's a bunch of hydrogen
| in compost so maybe that would fuse.
| jabl wrote:
| Maybe it could work via the CNO cycle:
| https://en.wikipedia.org/wiki/CNO_cycle ?
| Server6 wrote:
| Fusion can be a chain ration. In stars its caused by
| intense uninterpreted gravitational pressure. In the H-Bomb
| its triggered by a smaller fission explosion. Fusion chain
| reactions just require so much energy its hard (if not
| impossible) to harness on a commercial level. One small
| break in the the chain reaction containment and it falls
| apart.
| throwaway894345 wrote:
| Probably a dumb question, but what are the potential
| environmental impacts of manufacturing lots of helium? Is it
| a greenhouse gas? Even if we pivoted to 100% fusion in the
| next 100 years, is there a chance of releasing enough helium
| that it would be a problem in practice? I assume we won't
| need to worry about running out of hydrogen considering all
| of the water in the world (provided we can efficiently get
| hydrogen from the more abundant ocean water rather than the
| limited fresh water)?
| ngngngng wrote:
| UK accents will acquire a slightly higher pitch over time
| mbg721 wrote:
| Yet another way Monty Python was ahead of its time.
| mocko wrote:
| Not much - it's lighter than the atmosphere so rises to the
| top and floats off into space.
| XorNot wrote:
| Helium doesn't persist in the atmosphere. The mean free
| velocity of helium gas is above escape velocity, so all of
| it leaves Earth for outer space.
| throwaway894345 wrote:
| Whoa, I didn't realize that was possible. Fascinating.
| ClumsyPilot wrote:
| We have a shortage of helium on Earth, we are running out
| fast, all hydrogen produced can be put to good use.
| 317070 wrote:
| That does not seem right, we have literal oceans of
| hydrogen?
| ClumsyPilot wrote:
| sorry I meant helium, that was a brainfart
| WastingMyTime89 wrote:
| Yes but no at the same time.
|
| We still have plenty of helium. It's a byproduct of oil
| extraction and is still often vented because it would not
| be profitable of capturing it.
| gwd wrote:
| In fact, my understanding is that, not counting nuclear
| fusion, helium is a non-renewable resource critical for
| some kinds of critical uses like medicine; and that our
| current habit of putting it in balloons is considered
| rather reckless by people taking a longer view of things.
| If we could capture that helium, it would make things a lot
| better.
| throwaway894345 wrote:
| Capturing and using gases doesn't typically prevent them
| from ending up in the atmosphere, unfortunately.
| gambiting wrote:
| Like others have said though - helium escapes our
| atmosphere naturally and quite literally leaves Earth.
| That's how we're loosing all of our supply - it's just
| being vented into space constantly.
| FridayoLeary wrote:
| Helium balloons will stop working and everyone will have
| high- pitched voices.
| chriswarbo wrote:
| > Is it a greenhouse gas?
|
| Certainly not in the conventional sense (although perhaps
| there's another way that helium might act similarly to a
| GHG that I'm not aware of).
|
| Greenhouse gasses are _molecules_ , i.e. multiple atoms
| bonded together. Those molecules can absorb photons of
| infrared light, which cause them to vibrate (as if the
| atoms were held together by springs). After some time, the
| vibration stops and an infrared photon is emitted.
|
| The problem is: those photons are emitted in a _random_
| direction, unrelated to the photon that was absorbed. Half
| the time they will go roughly upwards, half the time they
| 'll go downwards.
|
| A photon of visible light (from the Sun) can travel down
| through the atmosphere without interacting much with the
| greenhouse gasses, since it has too much energy to be
| absorbed. This visible photon _can_ be absorbed by other
| materials at ground level, e.g. by a plant, and its energy
| will eventually result in around 20 lower-energy infrared
| photons being emitted back up (on average).
|
| These 20 infrared photons are _readily_ absorbed by the
| greenhouse gasses, and each time they 're absorbed, they
| get re-emitted in a random direction: half the time heading
| upwards again, but half the time heading back to the
| ground. This is how energy gets "trapped" by greenhouse
| gasses.
|
| Helium is almost completely unreactive: it doesn't form
| molecules in the atmosphere, it just bounces around as
| individual atoms. Without bonds to vibrate (or asymmetries
| to spin), the only way it can absorb energy is by speeding
| up, and even this isn't very effective since its mass is so
| low. Fast-moving helium is also more likely to escape the
| Earth's gravity completely.
| willis936 wrote:
| Don't worry, even if all energy humans used was from D+T
| fusion today it would only create 60% of the helium that we
| use. Also, helium is so light that it leaves the atmosphere
| so we really don't have access to much anyway.
| joshmarinacci wrote:
| Sort of, but it's a vast oversimplification. Fission is very
| safe relative to something like coal because all of the
| pollution is concentrated in barrels instead of pushed into the
| atmosphere, but has the risk of meltdown. To be fair lots of
| other non-nuclear plants have had disasters that released toxic
| gasses around the globe too.
|
| Fusion in theory has no pollution at all, but that's
| theoretical until large scale fusion plants are built.
| rcpt wrote:
| Another byproduct of fission is "long-time nuclear waste
| warning booty shorts" https://twitter.com/mochasucculent/stat
| us/125638615465338060...
| jeffbee wrote:
| Fusion reactors don't create fission products, obviously, but
| why wouldn't fusion create radioactive waste via neutron
| activation? Materials exposed to neutron flux, in any kind of
| device, may be activated into radioactive isotopes.
| willis936 wrote:
| Yes, but first wall materials are chosen to have a high
| melting point and short half life when activated. Close the
| building off for 100 years then scrap it. It's a far cry
| from the myriad of nightmare scenarios fission plants need
| active control against.
| slipframe wrote:
| Closing the building off for 100 years might work fine,
| but that can't be the solution to _every_ problem, it
| wouldn 't be economically viable. Ostensibly simple
| matters like routine maintenance are very complicated
| propositions for fusion reactors; you can turn the
| reactor off but it will still be too radioactive for
| anybody to work inside. So you either need some
| sophisticated robotics to repair anything that might ever
| need repairing, or you have to consider the entire
| reactor to be disposable.
|
| Of course, repairing things inside a fission reactor is
| no less nasty, but fission reactors are comparably much
| simpler and much smaller. Swapping a fission reactor out
| with a new one is comparably much easier than with a
| fusion reactor.
| BobbyJo wrote:
| A good way to think of the difference is:
|
| Fission requires effort to control. When things go wrong it
| isn't controlled.
|
| Fusion requires effort to create. When things go wrong it isn't
| created.
| jeffbee wrote:
| That seems like a faulty explanation. Uncontained fusion is
| massively energetic and destructive. The device in this
| article is analogous to an H-bomb weapon with a pneumatic
| rather than fissile primary.
| cogman10 wrote:
| Fusion bombs are when you put fusible materials next to
| fission explosions.
|
| Yes, they are massively energetic, (we wouldn't be
| harvesting power from it if they weren't.) However, they
| require a very high input energy to trigger the release of
| the output energy.
|
| With a fission reactor meltdown, the way you get there is
| by pulling out dampening rods or boiling off all the water,
| but otherwise leaving the fission rods in the same place.
|
| With a fusion reaction, you have to be constantly providing
| both the energy to keep the fusion going AND the input
| material to be fused. Interrupt one or the other and fusion
| stops.
|
| I know it seems weird that the bigger energy release is
| safer, but that's how it is. It's the difference between
| requiring constant input into the system to produce power
| vs an idle system with no input producing power.
| tolbish wrote:
| Their explanation is not really faulty. FYI hydrogen bombs
| are mainly destructive due to fission, not fusion. The
| fusion step is primarily for bombarding the dangerous
| fissile fuel with neutrons.
| jeffbee wrote:
| That a fusion bomb has significant energy from fission
| doesn't seem germane. It still has a great deal of energy
| from fusion alone.
|
| I'm not trying to scaremonger fusion energy, but I think
| it's intellectually dishonest to portray is as
| fundamentally sound, with a binary outcome of either
| inertia or safe energy. This design relies on spherical
| compression to both initiate and confine the fusion. We
| should not discount the possibility that if it instead
| creates a cylindrical or elliptical confinement due to
| malfunction, it will just explode, at a minimum
| destroying the device. We know it is possible to initiate
| fusion with radial compression in a cylinder, because
| that's how an H-bomb secondary works.
|
| The main safety factor in these things comes from the
| fact that a fusion weapon needs hundreds of kilos of
| hydrogen, and they are experimenting with much smaller
| masses. That limits the destructive potential.
| tolbish wrote:
| It is more intellectually dishonest to bemoan the danger
| of "uncontained fusion" by citing the hydrogen bomb.
| BobbyJo wrote:
| It's not dishonest to portray it as fundamentally sound,
| because it is. Your argument is that 'If scaled up
| several orders of magnitude this device could cause
| dangerous explosions.' This ignores two very important
| realities:
|
| 1) There isn't a reality in which these devices get
| scaled up to that size. 2) The real danger with fission
| is radiation, not explosions, which fusion reactors will
| produce in smaller quantities than a banana farm.
|
| Pure fusion power, even in its largest, most powerful,
| Elon Musk fever-dream incarnation, is safer than even the
| safest fission reactor, because there is no way for it to
| create a boom larger than it's vessel was designed to
| produce.
| gambiting wrote:
| Yes, in the sense that fusion requires incredibly accurate
| magnetic fields to maintain, and the second there's _any_ issue
| with the reactor chamber, the reaction will just stop. The
| reactor itself cannot explode in any way shape or form, because
| there is nothing in there to explode. It also doesn 't produce
| any radioactive isotopes while running, it just fuses(hence
| fusion) hydrogen into helium, just like the sun does. You can
| just capture this helium and sell it to make baloons if you
| want.
|
| The reaction itself kicks off a huge amount of neutron
| radiation, which eventually makes the reactor chamber
| radioactive - that is the only radioactive waste that will have
| to be disposed safely eventually. But neither the fuel nor the
| resulting product are radioactive.
| adrian_b wrote:
| Most of the energy that is produced is in the neutrons, so it
| will be transferred as heat in whatever shield captures the
| neutrons and which will become radioactive.
|
| So most of the heat will have to be extracted from a
| radioactive material, with similar precautions like in
| fission reactors, where the heat is extracted from the
| radioactive nuclear fuel.
|
| I am very skeptical that fusion of deuterium with tritium or
| of deuterium with deuterium will ever produce "clean energy",
| even if they are the easiest fusion reactions, due to the
| relatively low temperatures required for them.
|
| It still remains to be proven whether the radioactive waste
| for a fusion reactor of the kinds attempted now will be less
| than for a fission reactor.
| gambiting wrote:
| >>It still remains to be proven whether the radioactive
| waste for a fusion reactor of the kinds attempted now will
| be less than for a fission reactor.
|
| I wonder, how can this possibly be even a question? Fission
| based reactors obviously have the same or worse problem of
| irradiating the entire reactor enclosure and everything
| around it, so that's at best the same as a fusion reactor +
| they produce tonnes of very highly radioactive waste that
| will be radioactive for millennia.
|
| Materials activated through neutron bombardment aren't
| radioactive for anywhere near as long. And to add to that,
| nearly all elements produced in a fission reactor are
| highly toxic in addition to being radioactive - in a fusion
| reactor if your steel containment chamber becomes
| activated, you just have radioactive steel, not one of the
| many many dangerous heavy metals produced through fission.
| mikro2nd wrote:
| What is the sort of lifetime (ball-park) that one might
| expect before neutron saturation of the reactor walls becomes
| a serious concern and the reactor has to be scrapped?
| eloff wrote:
| I imagine you just replace the shielding on the inner
| walls, not the entire reactor.
| meowkit wrote:
| You can read about stuff like that in some of the ITER
| technical reports. They actually want to use that neutron
| radiation to generate tritium, and feed that back into the
| reactor.
|
| I don't think the reactor would be scrapped, just shutdown
| for maintenance.
| bobsmooth wrote:
| General Fusion's approach doesn't use magnetic confinement.
| Instead, they use liquid metal and pistons to create the
| pressures needed for fusion. The liquid metal then absorbs
| the heat energy which is extracted in the usual way.
| bobsmooth wrote:
| I think General Fusion's approach is one to keep an eye on.
| Instead of magnetic confinement, they use pistons to compress
| liquid metal into which the fuel is injected. The force of the
| collapsing liquid causes the fuel to fuse, releasing energy which
| is captured by the metal and then extracted with a heat
| exchanger.
| Shadonototro wrote:
| so it begins, after lobbying in EU for exiting Nuclear energy,
| specially in France
|
| they are back to sell theirs ;)
|
| i knew it, wrote about it few years ago here
| honkycat wrote:
| IMO, a massive investment and proliferation of fusion reactors is
| humanity's last hope. Assuming it isn't already too late.
| jeffbee wrote:
| We could build the optically-coupled ground stations for the
| gravity-confined fusion power source around which our planet
| orbits at a small cost and within a few years.
| asimpletune wrote:
| Can you explain this more?
| jeffbee wrote:
| It kinda spoils the joke, but OK.
|
| The Sun is a self-sustaining fusion plasma that already
| exists. It is confined by its own gravity. It will continue
| running at a steady state for billions of years. Except for
| melanomas, this source of power is completely harmless to
| human life.
|
| In order to plug this thing into the electric grid, all we
| need to do is capture the free electromagnetic emissions of
| the Sun. We already have this technology, called a
| photovoltaic cell. The production of such cells is an
| industrial engineering problem. There are no technological
| barriers.
|
| Compare to "fusion power", for which the ignition,
| confinement, and exploitation of the energy are all
| _totally unsolved_ technological problems.
| _Microft wrote:
| That's solar power.
| _Microft wrote:
| Are they any faster to build than fission reactors? If not, we
| can as well start building fission reactors instead of having
| to get the technology right and then to build them. (If you
| insist on a type of nuclear power.)
| mchusma wrote:
| I think this makes 3 fusion projects aiming for 2025: SPARC,
| ITER, and this.
| 317070 wrote:
| It is no coincidence. If everything goes to plan, ITER will
| demonstrate first plasma in 2025, which will be a bit of a PR
| nightmare for ITER (as it will not have high Q's, and go out of
| operation for another 10 years after that).
|
| So a lot of alternatives, like SPARC, General Fusion, Lockheed,
| Tokamak Energy, Commonwealth Fusion, ... are all aiming to
| demonstrate in 2025 as well, because it will contrast nicely to
| the ITER approach costing a lot of government money. Anyone
| that will beat the Q of iter in 2025, might see more government
| funding flowing their way between 2025 and 2035, because they
| managed to do the same, but orders of magnitude cheaper.
| boringg wrote:
| 2025 will come and go. 2030 more likely. Hope to be incorrect.
| BitwiseFool wrote:
| Fusion will be available during the Year of the Linux
| Desktop.
| boringg wrote:
| Haha. As someone who works deeply in the energy industry
| timelines and scope creep always happen. Sales/project
| development is so aggressive on timelines and the unknown
| unknown pretty much always blow up timelines. That and
| regulatory issues. Chances of Fusion delivering in 2025 is
| pretty low but I appreciate the optimism. Downvote away
| with your rose colored glasses.
| briffle wrote:
| Don't forget Lockheed Martin, that said they would have one
| about 15 years ago "in 2-3 years"
| [deleted]
| FridayoLeary wrote:
| Amazon Prime Energy. Delivered to your front door (and beyond).
| boringg wrote:
| Why'd they build it in the UK instead of the US? Curious about
| the location.
| danpalmer wrote:
| They're extending an existing team/experiment/project called
| JET. https://ccfe.ukaea.uk/research/joint-european-torus/
| fanf2 wrote:
| Culham also hosts the MAST reactor, and has been a fusion
| research site since the 1960s
|
| https://en.wikipedia.org/wiki/Culham_Centre_for_Fusion_Energ.
| ..
| twic wrote:
| And Tokamak Energy is about five miles away:
|
| https://www.tokamakenergy.co.uk/
| andruc wrote:
| Given it's a collaboration between a Canadian company and a UK
| research program, I'm not sure why the US would be considered.
| boringg wrote:
| US private investment - more opportunity for fusion reactors
| in US if progress is indeed proved out. Collab between the
| two does justify the reason though.
| buggeryorkshire wrote:
| According to the BBC there was a large consideration paid for
| by the UK Government.
|
| This isn't a criticism of them btw - it's exactly the sort of
| thing we should be subsidising - but it may explain it.
| boringg wrote:
| Makes sense - looks like UK is trying to building on being a
| specialist in fusion tech.
| ClumsyPilot wrote:
| I would rather have UK gov invest in the company than
| "subsidise" - it is not clear why it is fair to subsidise
| this company as opposed to other start-ups in this space.
| nomoreplease wrote:
| > It won't generate power, but will be 70% the size of a
| commercial reactor.
|
| That surprised me. At 70% of the size for $400M, I wonder why
| they didn't just try to build a commercial reactor in one go
|
| Is this the a mid-step between a small demo and a full reactor?
| What do they do with the building after they've tested it?
| thinkcontext wrote:
| Yes, its a mid-step.
|
| They don't know exactly how to build a commercial reactor yet.
| The scale they've worked at so far tests the basic design but
| it can't break even (no fusion reactor has yet) or function
| continuously. They are going to build the minimum size that
| they think will achieve these goals but it will also have to be
| capable of testing to be able to fine tune operation. A
| commercial reactor wouldn't be built like that.
|
| Also, keep in mind that cost doesn't scale linearly. Likely
| cost goes up with the cube of the size or higher.
| mullingitover wrote:
| I honestly don't understand why there's so much focus on fusion.
| It's an inferior method of producing energy - extremely fussy,
| still produces nuclear waste, still capable of producing nuclear
| weapons material, and has yet to deliver a net surplus of
| energy[1]. When I was younger I never saw a peep about the
| nuclear waste and nuclear proliferation problems with fusion - it
| was just pitched as this miracle technology that was ten years
| away. I was really excited about it, but the more I learn about
| fusion the more it appears to be a giant money bonfire.
|
| We'd be better off just coming up with good fast breeder reactor
| designs that have good safety measures. A breeder reactor can
| burn its fuel completely, it's a tried and true technology and
| it's our best shot at eliminating fossil fuels.
|
| The fusion research is important science, and I completely
| support researching it, but it's not a technology that's going to
| be commercially useful in our lifetimes and it's not better or
| cleaner technology than modern fission reactor designs.
|
| [1] https://thebulletin.org/2017/04/fusion-reactors-not-what-
| the...
| MisterTea wrote:
| > still produces nuclear waste,
|
| Yes but you only have to worry about radioactive reactor parts
| and other structural materials, not spent fuel.
|
| > still capable of producing nuclear weapons material,
|
| I don't get this argument at all. A fusion reactor does not
| generate heavy elements such as uranium or plutonium. However,
| the fusion reaction can be a neutron source which could be used
| to convert heavy elements such as thorium or uranium into
| fissile material. But by no means would this be part of any
| power generation station. This leads us to...
|
| > We'd be better off just coming up with good fast breeder
| reactor designs
|
| So this neutron source is somehow more clean and secure than
| the other one you just dismissed?
| a1371 wrote:
| It's a pretty big logical jump to say fusion has proliferation
| problem because it creates a neutron stream. It will be as if
| they build the Hadron collider to warm up soup. It's unrelated
| to the plant operation, unlike fission.
|
| I think this highlights the bias in the article you shared.
| Moreover, it solely focuses on ITER which is not a great
| example any more.
|
| Fusion doesn't really have the problems of fission. Because
| fusion has been extremely underfunded, the money is being spent
| extra carefully on ITER. But MIT SPARC is using new super
| conductors to get much smaller reactors.
|
| Reactors will produce some low level waste, but once we get a
| handle of the confinement, that issue can be eliminated with
| hydrogen isotope mixes. Also, Tokamak is only one fusion
| design, there may be better ways to capture the neutron stream.
| mullingitover wrote:
| These are all valid points, and I'm not saying we shouldn't
| do research on fusion. It certainly has promise. However, I
| don't think it has a serious chance of pulling a _deus ex
| machina_ move and saving us from climate change in our
| lifetimes. A solid energy source a century from now? Sure.
| Fission on the other hand has a good chance of uprooting the
| fossil fuel industry, and combined with other renewables is
| our best chance of getting carbon emissions to a place where
| civilization _might_ not go into a bronze age-style collapse
| from climate change.
| willis936 wrote:
| As an industry insider: everyone knows this. Fusion isn't
| the technology that saves mankind in this century, but it
| _is_ the technology that mankind needs to have working by
| the next century if we want to stay on our current
| industrial track. The march of progress might halt if we
| run out of ever-increasing access to free energy.
| jkelleyrtp wrote:
| > nuclear proliferation problems with fusion
|
| We already have fusion bombs. Building fusion reactors wouldn't
| impact nuclear proliferation at all. I really can't think of a
| single fusion reactor design that produces "nuclear weapons
| material." If fusion designs made nuclear material, then we'd
| probably already have nuclear-material-producing fusion
| reactors.
|
| I find it strange that you think breeder reactors are the way
| to go. Fusion's challenges are rooted in engineering - creating
| magnetic fields, heating plasma, breeding tritium. Fission's
| challenges are in public sentiment, exuberant costs, and
| dealing with extremely toxic metals.
|
| > it's not better or cleaner technology than modern fission
| reactor designs
|
| The "nasty ingredients" in fusion are deuterium, tritium,
| lithium, and irradiated confinement metal (think eutectic
| materials like stainless steel). The "nasty ingredients" for
| fission are much, much worse - both in products and required
| inputs.
|
| Fusion promises energy generation without the high atomic
| count; this makes the inputs easier to acquire, the risk of
| catastrophe much lower, and allows more flexibility in design
| (scale, cost, efficiency targets).
| jabl wrote:
| > Building fusion reactors wouldn't impact nuclear
| proliferation at all. I really can't think of a single fusion
| reactor design that produces "nuclear weapons material."
|
| Since a fusion reactor would produce an intense neutron
| field, it doesn't take a genius to figure out that if you
| line the reactor vessel with natural uranium, you have a
| device for producing plutonium. That is by no means a
| showstopper, but it means fusion plants will need 24/7
| security, IAEA inspections, worries when/if suspicious tinpot
| dictator states decide that they will need their own fusion
| power plants, etc. etc. Even if we'd magically solve the
| technical challenges in fusion, we won't be seeing things
| like dinky fusion-powered ships sailing around the oceans
| (for larger ships, one could envision some kind of IAEA
| monitoring system for those).
|
| Of course, if someone figures out aneutronic fusion (pB11 or
| such), these proliferation concerns would evaporate. That's a
| pretty big if, though.
|
| > dealing with extremely toxic metals.
|
| Spent fuel, in particular, is certainly radiotoxic, but
| chemically, no, not _that_ big of a worry. Society routinely
| deals with other toxic heavy metals like lead as well, not to
| mention all kinds of other extremely toxic compounds.
| jkelleyrtp wrote:
| Fusion power plants are certainly not the only thing we
| have that makes neutrons. You can buy neutron sources
| suitable for irradiating fissile material without having to
| build a fusion power plant.
|
| Fusion power plants would also be a terrible place to
| irradiate uranium. Getting material in and out would be a
| total hassle and you wouldn't necessarily be able to
| control the reaction.
| mullingitover wrote:
| > Fission's challenges are in public sentiment, exuberant
| costs, and dealing with extremely toxic metals.
|
| I'd argue that a lot of the public sentiment problems with
| nuclear were PR'd into existence by the insanely powerful and
| wealthy fossil fuel industry to which fission is a very real
| existential threat. If we're talking about exuberant costs,
| fusion beats fusion hands down and has yet to deliver a
| single net watt of power. The waste disposal is more of a
| political problem than a technical one.
|
| Overall, the problems with fusion are hard technical
| problems, and the problems with fission are self-imposed
| political ones pushed by the fossil fuel extraction industry
| that fission could very realistically replace.
| heimdall wrote:
| Unfortunately, we live in a world where public opinion
| (skewed by fossil fuel companies or otherwise) is a huge
| driving force. We can lament what the world would be like
| if only people were more knowledgeable, but at the end of
| the day it's the ecosystem we have to operate in.
|
| Fusion power has indeed had high R&D costs, but so has any
| significant project before the ROI starts to kick in.
| Fusion power (especially the types that don't generate a
| neutron flux) is safer and more productive in principle
| compared to fission, and I have high confidence I will live
| to see a commercial fusion reactor come online in my
| lifetime.
| Retric wrote:
| While it would last a long time at current levels, the
| supply of fission materials is quite limited when you're
| looking into interstellar travel etc. That's really the
| promise of fusion it's an unimaginably vast energy source
| for the future.
|
| As to more sort term concerns, fission has a lot of very
| expensive requirements like 24/7/365 security which make it
| difficult to integrate with vastly cheaper renewables.
| Baseline power sources like nuclear and coal wind are at a
| massive disadvantage when integrating with significantly
| cheaper wind and solar. They lose significant amounts of
| money during part of the day and need much higher premiums
| the rest of the day to make up for it.
|
| In today's energy market there is definitely a place for
| fission. However, with a 50 year payback period you need to
| project into future energy markers with even cheaper solar,
| wind, and batteries. That's why electricity companies
| generally view it as a dead end. Fusion is a larger
| unknown, it's probably not going to be cost effective but
| it's also the kind of long shot that might just pay off.
| jabl wrote:
| > the supply of fission materials is quite limited when
| you're looking into interstellar travel etc
|
| Yeah, sure, if we're gonna get a big spaceship to even a
| small fraction of light speed, that would require
| absolutely stupendous amounts of energy.
|
| But lets worry about that after we avoid cooking
| ourselves with GHG emissions? We might or might not have
| enough fission fuel for large-scale interstellar travel,
| but certainly more than enough to get rid of fossil
| fuels.
|
| > fission has a lot of very expensive requirements like
| 24/7/365 security
|
| So will fusion, unfortunately, unless someone figures out
| aneutronic fusion, which is a much longer shot than D-T
| fusion most efforts are concentrating on.
|
| I'm all for spending a lot more on fusion R&D though; the
| potential win is just so enormously large that it makes
| sense to bet some amount of resources on it, just in case
| it works out.
| fastball wrote:
| Working on fusion doesn't mean we're not working on better
| fission. We should do both. I think both fusion/fission are
| great but your comment is misleading at best.
|
| - Fusion produces much less radioactive waste byproducts then
| fission. It's not zero, but it's a significant difference.
|
| - The problems with nuclear weapons proliferation are _much_
| easier to handle with fusion. For starters, you 're not
| transporting enriched uranium fuel around. Also you don't end
| up with fun transuranics like plutonium which can be readily
| used to make weapons, unlike any key byproducts of fusion.
| Hell, the main byproduct of our fusion reactors is gonna be
| Helium, which we actually need more of because it is a very
| useful element that experiences shortages due to not being
| contained in the atmosphere and not being super prevalent in
| the earth's crust.
|
| - "Extremely fussy" is a selling point. Extremely fussy means
| that if something goes wrong you don't have a runaway chain
| reaction that makes everything go boom. It's impossible to
| design a fusion reactor that can melt down. Meanwhile, melting
| down is the default mode for fission reactors and needs to be
| carefully designed around.
|
| - Fusion is the only viable energy source for long-term space
| travel/colonization.
|
| - The point about net energy surplus is kinda nonsensical. Of
| course we're not there yet, that's why it's a problem we're
| actively working on and not something we've already solved.
| Your point is literally "we shouldn't develop this technology
| because we haven't developed this technology yet".
|
| Also not sure how we can simultaneously need to "come up" with
| a good fast breeder reactor design while at the same time it's
| apparently "tried and true technology".
| mullingitover wrote:
| > - "Extremely fussy" is a selling point. Extremely fussy
| means that if something goes wrong you don't have a runaway
| chain reaction that makes everything go boom.
|
| Sorry, I should've elaborated a bit on this point. I'm
| talking about the expensive containment system which will be
| subject to extreme conditions and have a short lifetime[1].
|
| > Under reactor-relevant conditions, the following are the
| most serious damaging mechanisms: thermally induced defects
| such as cracking and melting of the plasma-facing material
| (PFM); thermal fatigue damage of the joints between the PFM
| and the heat sink; hydrogen-induced blistering; helium-
| generated formation of nanosized clusters; and neutron-
| induced degradation of the wall armor via reduction of the
| thermal conductivity, embrittlement, transmutation, and
| activation.
|
| > Further serious lifetime-limiting PWI processes are caused
| by material irradiation with hydrogen isotope ions (D+ and
| T+) and impurities that--depending on their impact energy--
| will sputter the wall material. The eroded species will be
| deposited elsewhere, for example, on unshielded parts of the
| vacuum vessel, on blanket modules, or on less severely
| exposed divertor targets (outside the separatrix strike
| zone). Implantation of hydrogen isotopes into the surface of
| the PFM will result in severe embrittlement of the wall. This
| also has a strong impact on its cracking resistance, in
| particular during short transient thermal loads (i.e., ELMs).
| Helium will also be implanted into the surface of the wall
| armor or buried in redeposited surface layers. Implanted
| helium tends to migrate (depending on the prevailing
| temperature) and to form tiny bubbles that again can interact
| with implanted hydrogen. In several fusion-relevant PFMs
| (e.g., tungsten) helium can initiate rather substantial
| changes in surface morphology, such as the growth of tiny
| tendrils or "fuzz" on the surface of the PFM.12 These layers
| can easily reach several micrometers in thickness. These
| effects need to be considered as a potential source for the
| release of dust particles and contamination of the burning
| fusion plasma.
|
| So I'm not talking about the fail-safe nature but rather the
| extreme cost and technical difficulty of containing the
| reaction for the amount of time that would be needed for
| fusion to be a viable commercial energy source.
|
| [1] https://aip.scitation.org/doi/10.1063/1.5090100
| phs2501 wrote:
| I think one of the advantages of the General Fusion
| approach is that both what the heat gets transferred to and
| what bears most of the neutron flux (and hence gets
| irradiated) is the liquid metal, which is presumably easily
| replaced (and could presumably even be done incrementally
| while the reactor is live, since it's going to be flowing
| through a heat exchanger anyway)?
| k__ wrote:
| Shouldn't (at least) the USA have enough sub tropical geography
| for solar panels?
| mullingitover wrote:
| We definitely do! However the rate that solar can be added is
| nowhere near fast enough to replace fossil fuels in a
| timeframe that meets our climate goals and prevents
| environmental catastrophe[1].
|
| > Solar and wind power alone can't scale up fast enough to
| generate the vast amounts of electricity that will be needed
| by midcentury, especially as we convert car engines and the
| like from fossil fuels to carbon-free energy sources. Even
| Germany's concerted recent effort to add renewables--the most
| ambitious national effort so far--was nowhere near fast
| enough. A global increase in renewables at a rate matching
| Germany's peak success would add about 0.7 trillion kilowatt-
| hours of clean electricity every year. That's just over a
| fifth of the necessary 3.3 trillion annual target.
|
| > To put it another way, even if the world were as
| enthusiastic and technically capable as Germany at the height
| of its renewables buildup--and neither of these is even close
| to true in the great majority of countries--decarbonizing the
| world at that rate would take nearly 150 years.
|
| [1] https://www.wsj.com/articles/only-nuclear-energy-can-
| save-th...
| 7952 wrote:
| It seems unfair to compare a hypothetical nuclear build
| rate to a real one in renewables. We just don't know if a
| nuclear industry could get anywhere near the deployment
| rate required.
| mullingitover wrote:
| You're right, and I'm not saying we should slow down on
| solar, but based on the numbers, solar alone is not going
| to get us where we need to be, so we should be pushing
| the nuclear industry to find out how fast they can deploy
| and bulldozing a path for them while we also push for
| faster deployment of solar.
| westoncb wrote:
| > However the rate that solar can be added is nowhere near
| fast enough ...
|
| Any idea what the bottleneck(s) is/are?
| 7952 wrote:
| In the UK substation capacity is a constraint. Rural
| connection points tend to have limited capacity to export
| to the wider grid.
| thehappypm wrote:
| You don't even need sub tropical.
|
| Massachusetts, in the Northeast, is showing a real-world
| strategy for solar.
|
| Massachusetts incentivizes homeowners to have their own solar
| installs. My house, for example, has solar, as do many houses
| in my town. Yesterday it produced about 50 kWh, meaning I was
| sending energy into the grid.
|
| You might ask, what's the point of solar if there's no
| storage? Going 100% renewable would be amazing, but reducing
| CO2 is a win. If electric load declines because more and more
| homes can produce their own electric, that's a huge reduction
| in total CO2 that needs to be produced at the power plants.
| It doesn't mean we can throw away the gas plants, but they
| can be run at lower capacity. Storage isn't really discussed
| yet, but maybe one day we'll get there.
|
| We're also investing in a huge offshore wind farm.
| StreamBright wrote:
| Finally something mildly interesting coming from Bezos. I guess
| he is bored out of his mind at this stage.
| wpasc wrote:
| I agree, if capitalism and the free market is to produce
| individuals who have fuck-you-money^2 then it would be great if
| they did interesting/innovative things that the market as a
| collective may pass on as being too risky and/or researchers
| can't get the funding for bc there's not enough money or the
| grant seems too risky.
| [deleted]
| merpnderp wrote:
| If Bezos is paying for it, then by definition the market is
| investing in it. Unless you think Bezos's money exists
| somehow outside of the market.
|
| When I invest in an ice cream cone, that ice cream is about
| to be destroyed and my investment will soon be down the
| toilet, but I was certainly participating in the market. If
| Bezos's reactor blows up, it will be little bits of the free
| market raining down. And if it powers the world with endless
| green energy, there will be little green energy free market
| electrons pumped across the world.
| [deleted]
| adrianN wrote:
| Very cool. I like that we spend money on alternative routes to
| fusion. Funding has been so sparse in the last decades that
| tokamaks essentially sucked up all of it. Maybe other approaches
| can be built smaller and cheaper.
| ben_w wrote:
| > Hundreds of pneumatic pistons are then used to compress the
| plasma until the atoms fuse, generating massive amounts of heat.
|
| _Pneumatic pistons_? How is air pressure even close to enough
| force to make the slightest difference to a fusion reaction?
| lumost wrote:
| It's a question of relative scale. If you have big enough
| pistons squeezing a small/light enough amount of plasma then
| you could make the pressure work.
|
| It's great to see non-tokamak designs being developed
| mikeyouse wrote:
| See "Compressed Gas Drivers" here for their description..
|
| https://generalfusion.com/technology-magnetized-target-fusio...
|
| There's a longer video on that page as well with more details.
| DennisP wrote:
| I have no idea how much compression they get, but I do know
| they're targeting a middle range between magnetic fusion (low
| density, long confinement) and inertial fusion (high density,
| short confinement).
| kwhitefoot wrote:
| It's not air pressure, it's a shock wave in liquid metal.
|
| The BBC article is simplified a bit too far for anyone with a
| technical background but I doubt if a more accurate version
| would be much more meaningful to most people.
|
| There is a patent on it:
| https://patents.google.com/patent/US9424955B2/en
|
| ----Quote:
|
| 2. Description of the Related Art Various systems for heating
| and compressing plasmas to high temperatures and densities have
| been described. One approach for accomplishing plasma heating
| and compression by spherical focusing of a large amplitude
| acoustic pressure wave in a liquid medium is described in U.S.
| Patent Publica tion No. 2006/0198486, published Sep. 7, 2006,
| entitled "Pressure Wave Generator and Controller for Generating
| a Pressure Wave in a Fusion Reactor", which is hereby incor
| porated by reference herein in its entirety. In certain embodi
| ments of this approach, a plurality of pistons is arranged
| around a substantially spherical vessel containing a liquid
| medium. A vortex or cavity is created in the liquid medium. The
| pistons are accelerated and strike the outer wall of the vessel
| generating an acoustic wave. The acoustic wave generated in the
| liquid medium converges and envelopes a plasma that is
| introduced into the Vortex, thereby heating and compressing the
| plasma.
|
| ----end quote
| hellgas00 wrote:
| They mention steam in their demo video drives the primary
| pistons, which in turn drives a 2nd set of pistons that contour
| a liquid metal chamber, which in turn compresses the fuel
| mixture.
| rob_c wrote:
| How and when did general fusion become a Besosian company ?!...
| ClumsyPilot wrote:
| The article should be featuring Dr. Michel Laberge who actually
| funded the company, or other scientists, not Besos.
|
| Perspective given in the article belittles great strides made by
| fusion pioneers and poisons discussion on public policy:
|
| Fusion has advanced faster than Moore's law - and unlike the holy
| grail of computing, true AI, it's now clearly within reach.
| https://www.reddit.com/r/pics/comments/hsmge/moores_law_for_...
|
| >"Frustrated by the slow progress, private companies [innovate]"
|
| This is not about frustration, it's about opportunity:
|
| After decades and billions spent on research and engineering, all
| "open source", and training a generation of plasma scientists,
| venture capital can hire these people into profitable ventures.
| I'd like to ensure these people are given proper credit, and
| actually make some money off their great contribution to
| humanity.
|
| I fear that all we will do to reward greatest minds is give them
| mediocre jobs.
| StreamBright wrote:
| "A billionaire gambles with an insignificant portion of his
| wealth" the real title.
| bobsmooth wrote:
| Why so pessimistic? GF has a novel approach to fusion and I'm
| ecstatic that they're actually building a proof of concept.
| bla3 wrote:
| > it's now clearly within reach that graph ends more than 20
| years ago and implies that some important threshold should've
| been crossed 15 years ago. Did that happen?
| [deleted]
| phreeza wrote:
| "Fusion Energy: Research at the Crossroads - ScienceDirect" h
| ttps://www.sciencedirect.com/science/article/pii/S254243511..
| .
|
| Figure 1 has an update showing that the exponential
| trajectory has stalled.
| [deleted]
| JumpCrisscross wrote:
| > _article should be featuring Dr. Michel Laberge_
|
| Low chance it would have made the Hacker News front page if it
| did. Unfortunate as it is, the newsworthy component is Bezos's
| endorsement. Otherwise, it's another fusion start-up.
| foobarian wrote:
| It's not like fusion start-ups don't routinely make the HN
| front page :)
| phreeza wrote:
| While interesting, the figure you linked is from 2003. Is there
| an updated version that includes the last 2 decades?
|
| Edit:
| https://www.sciencedirect.com/science/article/pii/S254243511...
|
| Figure 1 has an updated version, and it is rather bleak.
| rcpt wrote:
| Reading the article doesn't leave me with the impression that
| this is "bleak"
| ClumsyPilot wrote:
| You can't expect exponential progress to continue forever in
| the world of atoms, so I disagree with your characterisation
| of "bleak". After all, that doesn't happen in any other non-
| software industry
|
| I don't have the knowledge to judge how much of this slowdown
| is due to the ITER project being international and difficult
| to manage, and how much of it is due to us approaching the
| limits of what is physically possible.
|
| However it's good to keep in mind that our level of funding
| for fusion is pathetic and scientists themselves have
| categorised it as "fusion never"
|
| https://upload.wikimedia.org/wikipedia/commons/a/ab/U.S._his.
| ..
| zamalek wrote:
| > You can't expect exponential progress to continue forever
| in the world of atoms,
|
| Fusion is usually more about electromagnetism, though.
| 7952 wrote:
| An amazing scientific achievement can be bleak in terms of
| actually applying the technology to real world problems.
| jessriedel wrote:
| I don't think the atoms point is right. Silicon
| semiconductors are made of atoms. Also, we get Moore's law
| like behavior in lots of very physical industries, e.g.,
| the cost of solar panels.
|
| A pretty simple model that accounts for the data is that
| Moore's law, and many other exponential growth examples,
| require ever larger capital expenditures. This worked for
| Moore's law because at ever step of improvement the devices
| produced were highly economically valuable. For fusion, on
| the other hand, you can have an exponentially improving
| triple product, but it has zero economic value until you
| cross the net-positive threshold. That basically means that
| the exponentially increasing development funding needs to
| be provided by the government, philanthropy, or some other
| non-profit source. If you're exponentially improving, with
| exponential costs, and you hit the ceiling of what the
| government and philanthropists are willing to provide, your
| progress can come to an abrupt halt without it necessarily
| meaning the basic exponential engineering curve you were
| following stops.
| ClumsyPilot wrote:
| I think the parallel between cost of semiconductor fabs
| increasing and costs of fusion reactors increasing is
| quite apt.
|
| But we don't actually have exponential improvement in any
| physical object, that's not to do with information
| processing - a solar panel or battery made today is not
| 10x better than one made 10 years ago.
|
| It's not even true of all semiconductors - power
| electronics, radio, etc.
| Judgmentality wrote:
| > But we don't actually have exponential improvement in
| any physical object, that's not to do with information
| processing - a solar panel or battery made today is not
| 10x better than one made 10 years ago.
|
| Do you understand how differently that reads from your
| original comment?
|
| > Fusion has advanced faster than Moore's law - and
| unlike the holy grail of computing, true AI, it's now
| clearly within reach.
|
| You made the claim it's advancing at a rapid rate and
| almost here, and when someone pulled up the data it
| wildly disagreed with you. Now you're just moving the
| goalposts.
| Animats wrote:
| _" Hundreds of pneumatic pistons are then used to compress the
| plasma until the atoms fuse, generating massive amounts of
| heat."_
|
| Huh? Pneumatic pistons?
| nickparker wrote:
| In the original General Fusion plan: Pneumatic pistons which
| strike anvils in the chamber wall creating a shockwave which
| implodes the liquid wall with fusion-igniting pressures.
|
| I think they may have moved away from that in favor of big
| pneumatic pistons pushing tiny piston heads directly into the
| liquid though. Mechanical advantage is the area ratio, which
| you can easily make quite large.
| DubiousPusher wrote:
| Question from a total ignoramus here.
|
| TLDR: Despite recent progress, is it possible that fusion will
| reach efficiency where it is net positive in energy output but
| still too expensive to be useful?
|
| Long Version: When I first heard about fusion, the idea was that
| this immense energy could be harvested taking advantage the the
| conversion of matter into energy. Everything I heard was that the
| quantities are so great that if we could just nail the sustained
| fusion reaction we could harvest potentially limitless energy.
|
| As I've come to understand it however, it is not so simple. The
| big question is in how long you can sustain the reaction and how
| much energy it costs to start it in the first place. It seems to
| me the strides that have been made over the last few decades are
| to bring the cost down enough and extend the reaction long enough
| that the net energy loss is lower, then break even and now
| possibly a net gain. I've seen some articles imply that this turn
| of events means fusion is definitely on the table as a near
| future abundant energy source.
|
| My question is this. Is it a forgone conclusion that the current
| trends will continue? Because if not, doesn't that mean fusion
| could still get stuck somewhere where there is a net energy gain
| but it's still too expensive to be useful?
| twanvl wrote:
| I don't expect building a fusion power plant to become cheaper
| than a gas power plant. Both need steam turbines, cooling
| pipes, a big building, etc.. So that would be a lower bound on
| the construction cost.
|
| If solar+batteries can outcompete fossil fuel plants (while
| ignoring fuel costs), then fusion likely wouldn't be viable
| commercially. And if you look at [the data](https://en.wikipedi
| a.org/wiki/Cost_of_electricity_by_source#...), we are already
| close to this point.
| spartanatreyu wrote:
| Yes and no.
|
| The first generation of fusion reactors will be expensive and
| monolithic, but we will learn a lot from them and it will prove
| their fundamental functionality.
|
| The second generation reactors will likely be using better
| fuels and squeezing plasma into different shapes to keep them
| running as long as possible.
|
| Even if other renewable energy sources continue to get cheaper
| and become prolific, they still have the problem of energy
| storage. Simply put, we don't have anywhere near the resources
| required to build all that storage. So what we need instead is
| a solid mainline energy source (nuclear and fusion).
|
| In the case of a massive breakthrough in energy storage, at
| best it will just delay fusion power. We will still need to use
| fusion off planet.
| hutzlibu wrote:
| "we don't have anywhere near the resources required to build
| all that storage."
|
| Sources?
|
| There are lithiumfree batteries, made from cheap metals.
| Saltwater batteries for example.
|
| Airpressure as energy storage.
|
| Hydrogen or more processed into methanol ....
|
| Etc., etc. all working technology as of today. And sure,
| sure, storage comes with lower efficency, but there is no
| reason, we cannot transform the various deserts into big
| solarplants.
|
| Fusion would be awesome to have. But I see no indication,
| that it will be ready anytime soon, when we need it, to
| produce clean energy at scale. And if it is ready, we
| probably still need resources, like Helium-3. Ready to mine
| the moon?
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