If we do the fusion in zero g then we have solved the confinement issue. The problem is creating conditions for fusion in zero g. The simplest way would probably be aggregating enough material to a single spot that gravity itself creates conditions for fusion. But then the power plant becomes too energetic for earth so it has to be at an enormous distance away to be safe. And with that of course you have the problem of transmitting the power back to earth. But I think photons could be gathered at a safe distance from this fusion, to harvest it without having to be so close.
The issue with that is how to direct the energy back to Earth, and then collect it. If you can’t direct it and it radiates in all directions then only a tiny fraction of the produced photons will reach Earth. Then you need to collect those photons in order to do useful work, otherwise they will just heat the earth. If the distance needed to remain safe is greater or less than geosynchronous orbit, you’ll need collectors all over the Earth as they won’t have constant line of sight towards the source and experience a “nighttime” of sorts. There is also the issue of atmospheric effects, such as high densities of moisture, absorbing or scattering the photons, reducing the efficiency of the collectors. So it could work, but the effective maximum capacity will always be quite limited and the overall process highly inefficient relative to the total fusion energy produced.
Actually you don't want the transmission process to be 100% efficient. If you really captured all the fusion energy transmitted (or even just the small part of it reaching Earth), all sorts of people would complain, trust me! But fortunately that fusion reactor has more than enough power to go around...
Maybe we can use the excess photons in another way? We could bio-engineer sunlight collection devices that would take in sunlight and use it to break apart CO2 and produce other useful materials. We could then spread them around the planet to use the excess photons in a productive way. We gain valuable complex molecules and break down CO2 so a win win!
There may also be a side business selling skin products to protect people who may be exposed to the radiation from this new reactor. Possibly people may even choose to vacation in areas of elevated radation, as it is likely to be warmer. Interesting...
If you only have one of them then the photons would only be available on that side of the earth at any given time and the other side wouldn't have power, but two of them would confuse the animals and disrupt everyone's circadian rhythm and then you'd have to deal with the three-body problem. Even the reactor-facing side would also have issues with the photons not getting through when it's cloudy.
The photons will also create heat and that heat can be used for useful work at any time, even when there are no photons hitting that side of the earth. For example it will evaporate water which will later condense into rivers, where you can put turbines. So it's a kind of fusion power, but less direct. Pure science fiction, of course.
It looks like ultimate goal of this is creating a self-sustaining fusion reactor approximately 1AU away from earth (for safety) and using photovoltaic arrays to absorb the energy... Ingenious!
That's what OP was implying. Energy (..and its derivative global warming ) is just infrastructure and finance problem now onwards. Balancing grid, Moving power from sunshine area to non-sunshine area, storing some power at night, handling fluctuation all are more or less solved problem. Fusion is just research subject ( ..or for may be powering colony on mars ? ).
.....
saying that, I hope our collective curiosity for fusion will take us to new inventions and space opportunities.
…is this an elaborate joke about solar power? And by extension, virtually all the energy that’s accumulated on the earth over the eons? It took me a minute :)
I did some back of the envelope calculations for this and it turns out that almost all life will eventually evolve to have reasonable protection against it. Except in Australia.
You'd have to stick it in a lagrange point 1.5M km away though since just in orbit is not true zero G.
Microwave energy transfer should work. That's what I like about the Helion fusion reactor design they don't use steam to power generators it's direct power no water or steam.
> This was a 25% improvement on the previous record time achieved with EAST, in China, a few weeks previously
I applaud this nuclear arms race. 22 minutes is really impressive for a technology that’s always been “20 years away”. I think I will do a deep dive on the technical challenges of fusion.
Not to downplay it, but it's still only half as hot as would be required of a commercial reactor. Also this reactor had no mechanisms to recover energy or neutrons to breed tritium. Still impressive and encouraging.
Right but that's what ITER is for. This type of research is to validate control systems which can be transferred to that project (i.e. prove you can do it, then prove its not machine-dependent).
I'm glad the bear case includes the "will never be economically practical" which is my core criticism of fusion, even with "high funding".
I also didn't see anything about vessel irradiation, which also never seems to be discussed. I get it probably isn't as big a problem as solid fuel rod fission in terms of waste creation, and tritium breeding may help, but it still will be kind of the same problem with LFTRs: a reactor design will fundamentally need an ongoing reconstruction/replacement strategy due to the vessel irradiation and transmutation from high energy neutrons.
Feel free to correct me if this isn't as big a problem as I think it is.
No, it's not. It's just a legit illustration of somethings state of development on fundamental levels. It simply means "we have no f**ing clue how we can do this, but future..". This is different from something we have already solved, and you just need to throw money on it to scale it to whichever level you need it.
> Cracking natural language comprehension with digital computers is an example from our field and it’s here.
That's the point, everything in research is always x0 years away, until the breakthrough happens and it's finished.
> Triple product (efficiency ) has increased faster than moors law for the last 50 years
Fusion research progress is underappreciated. But Moore's Law is for an existing industry. Prior to that, it took 10 ^ 6+ improvements in various technologies to make computing possible.
Not sure what you mean by that. There was a bunch of computing technology long before photolithography or even transistors. And mores law was coined in 1965 when individual chips had far less than 10^6 transistors while the first one was made by hand.
Moore's law is self propagating: improvements in compute beget improvements in compute by improving the computers used to design compute devices. fusion, while in an impressive bootstrapping phase, does not get that acceleration until commercial break-even.
moore's law is just the observation that chips are 2d: linear shrinks produce exponential benefit.
I can't see anything like a linear/square relation in fusion reactor design (even accepting that ML's premise of shrinks being linear in time is not a law, just something that sometimes happened, and sometimes didn't...)
Specifically they were able to maintain a tokamak plasma (presumably at fusion temperatures) for 1337 seconds, using two megawatts of heating. 1337 is not a joke; presumably the "leet" reading is coincidental.
With China spying around, you probably don't want to reveal the full potential of your technologies before you are sure that you will have permanent lead.
>> In the H-mode, a calm edge without turbulence reduces how much heat and how many charged particles the plasma loses. This leads to a sharp increase in pressure across the entire volume of the plasma, including the core where the conditions that can lead to fusion occur. The reduced energy and particle losses also minimize damage to the material surfaces surrounding the plasma.
Neutrons and photons pass through magnetic fields, so they always escape the plasma and provide heat that can be turned into steam. Keeping the plasma ions better confined doesn't impair energy recovery.
One issue I see for applying prediction markets to things like “there is a commercially successful fusion power plant before the year 2070” is the long time until resolution. Now, of course, one can hope to sell your shares in “yes” or “no” 5 years from now, but there may not be enough liquidity?
Suppose we had one prediction market M_1 for “On January 1st 2070, resolves ‘yes’ if there has been a commercially successful nuclear fusion power plant, and otherwise resolves ‘no’”, and then another market M_2 that, maybe it resolves in 5 years as ‘yes’ if the price of M_1’s ‘yes’ is greater than 30%? Or… hm, that seems problematic because people could just buy a bunch of M_1’s “yes” right before M_2 resolves? Or maybe that’s a self-correcting problem because people could… no, still seems like a problem..
Well, what if instead of a prediction market about the future value of another prediction market, it was futures contracts for the shares in a prediction market? Like, the right to buy or sell shares in “yes” or “no” at a particular price?
So like, if you’re confident that the prediction market will assign probability p or higher on a particular day 5 years from now, then if you bought futures which, on that day each of the futures could be used to sell a share in “no” at the price (1-p), then…
well, if the probability assigned to “yes” on that day is indeed p or higher, then the price of “no” would be (1-p) or lower, so one buy a share in “no” at a price less than (1-p) and then sell it at (1-p)..
Hm, issue there is one still needs to buy the “no” in order to sell it, so that doesn’t seem to really fix the “what if there is no liquidity in 5 years?” issue?
I guess one could spend 1 to create a share of “yes” and a share of “no”, and then sell the “no”, and be left with the share in “yes” which is ostensibly worth at least p, and then like, sell it a bit later when there’s more liquidity or something?
I probably don’t know what I’m talking about about this.
You should look into options - you're describing various forms of options contract.
None of them solve this problem, though:
> Now, of course, one can hope to sell your shares in “yes” or “no” 5 years from now, but there may not be enough liquidity?
In general, if there isn't liquidity in the primary market you should expect the derivative markets to be even worse. You would use options not to find extra liquidity - and binary options on illiquid markets like you describe are indeed particularly prone to market manipulation - but to express very particular views.
> another market M_2 that, maybe it resolves in 5 years as ‘yes’ if the price of M_1’s ‘yes’ is greater than 30%?
Like this one - you should buy this contract if you really do want to make a bet the price will be over 30%, and you don't care much about getting a big payday if the price is 90 or keeping most of your money if the price is 29.
The future value could be shared with the entire humanity.
For example, Bill Gates is going to die like everyone else and give most of the money away, like Warren Buffet.
They can spend a significant amount of money in life if they see nuclear fusion is possible, even if they do not recover the costs.
The only thing that is needed for this to happen is investors being confident that the money is not going to be wasted.
I personally know rich people that are betting a significant part of their wealth in fusion(millions USD) even when they know there is a risk that they will never recover the money.
Poor Bill Gates wants to give his money away, but he hasn’t gotten around to it yet. Why are we still pretending he is a philanthropist and not one of the biggest oligarchs of our time?
I don't think a long pay-off horizon is a problem for this market. It the same as for shares in companies that don't pay dividends. What creates a price for Berkshire Hathaway (BRK/A) if owning the share never gives you anything in the form of dividend? It's because in the far future, you can be confident they'll have enough money in the bank that they will pay out. Maybe not in your lifetime, but you can sell to someone, who'll sell to someone, etc. who will eventually collect a dividend. The market is so abstract that that pay-off time could be infinity years in the future and still, the share still has market value today.
How would you define "commercially successful"? The first fusion power plants will only get built with huge government subsides. Some governments like China look at this as a strategic, existential issue and will pay whatever it costs to make it work. They don't like being dependent on foreign fossil fuel supplies that the USA could easily interdict.
I’m in the USA and don’t like being dependent on foreign fuel supplies!
I think there was (maybe still possible?) a real missed opportunity to pitch green energy in a national security or America First way. I don’t think the average republican voter wants us to be as tied to OPEC the way we are.
We could still product as much—or more!—oil in Texas while reducing our care for anything in the Middle East.
Speculation with positive expected return is a good thing. So the question is, does fusion have positive expected return?
The world spends 10% of global GDP on energy, about $10 trillion per year. The world will spend something like a quadrillion dollars on energy this century, possibly more as the world gets wealthier and per capita energy use increases. A billion dollar investment is just one part in a million of that. Fusion doesn't have to be very likely to succeed to make such speculation worthwhile.
It’s not that I want to bet, but that I want a good probability estimate about whether commercially viable fusion power will be around by such and such date.
The location they have that's "well into construction" is SPARC, which is not intended to be a net power production facility. It will host their net gain demonstrator that they intend to have first plasma in next year and target a net gain demonstration in 2027.
ARC which they announced siting for and is intended to be their first grid-attached net power provider only just had the location selected so I don't believe its got much construction going on yet. The goal for that plant to be producing power is "early 2030s".
Ah, maybe not well into construction. But a friend of mine works with exotic materials and they are purchasing lots of things for ARC. Though I imagine these materials have a long lead time.
For people more aware of the fusion industry, what is it that stopped the plasma at 22 minutes (or lower times in alternate tests)? Did they just stop injecting power to maintain the heat as they achieved their benchmark?
Is this something where it's on the precipice and small tweaks bridges from 22 minutes to basically indefinitely?
Tokamaks need the central solenoid to have a current ramp, so at some point you run out of voltage. You can turn that way down, but you get less plasma performance. You're traditionally limited by heat rejection capabilities of the vacuum vessel.
These are science machines to learn about plasma and increase performance of future machines. A real reactor involves a lot of engineering to handle the heat rejection problem (and turn it into a revenue stream if you're clever). In terms of the pulsed nature: not really a problem if you keep the duty cycle high enough and maintain sufficient buffers in your coolant to keep the turbines happily turning away.
I learned recently that another limit to plasma duration is contamination. As fusion occurs and high energy particles that escape magnetic confinement blast the toroid wall, ions of metal get mixed into the plasma and degrade performance.
I've seen photos of what the inside of experimental tokamaks look like after many cycles. Metal is eroded away and deposited around the chamber in interesting patterns. Unfortunately a image search isn't surfacing the images I have in mind.
Readit News
‘Simpler’: move earth to where the energy goes: https://en.wikipedia.org/wiki/Dyson_sphere
Dead Comment
Space solar is an old idea and the Soviets/Russians have worked on it since the 70's; and nowadays, like most other Russian inventions the Chinese are commercializing it. https://www.ft.com/content/2d43ed21-9f9d-4e90-a18b-ad46f0a47...
If me move the reactor close enough to the center of the earth, eventually we can get to zero g. We then also solved the confinement problem.
Microwave energy transfer should work. That's what I like about the Helion fusion reactor design they don't use steam to power generators it's direct power no water or steam.
Deleted Comment
I applaud this nuclear arms race. 22 minutes is really impressive for a technology that’s always been “20 years away”. I think I will do a deep dive on the technical challenges of fusion.
I also didn't see anything about vessel irradiation, which also never seems to be discussed. I get it probably isn't as big a problem as solid fuel rod fission in terms of waste creation, and tritium breeding may help, but it still will be kind of the same problem with LFTRs: a reactor design will fundamentally need an ongoing reconstruction/replacement strategy due to the vessel irradiation and transmutation from high energy neutrons.
Feel free to correct me if this isn't as big a problem as I think it is.
Cracking natural language comprehension with digital computers is an example from our field and it’s here.
No, it's not. It's just a legit illustration of somethings state of development on fundamental levels. It simply means "we have no f**ing clue how we can do this, but future..". This is different from something we have already solved, and you just need to throw money on it to scale it to whichever level you need it.
> Cracking natural language comprehension with digital computers is an example from our field and it’s here.
That's the point, everything in research is always x0 years away, until the breakthrough happens and it's finished.
Not that it's not impressive, but LLMs do not "comprehend", for a start.
Exactly, there are experts in the field less than a decade a way who said 50+ years easily. And there we are.
Still people make jokes about fusion research, some things just take time.
I recommend this excellent review of the even more excellent book „The future of fusion energy“
https://www.astralcodexten.com/p/your-book-review-the-future...
Fusion research progress is underappreciated. But Moore's Law is for an existing industry. Prior to that, it took 10 ^ 6+ improvements in various technologies to make computing possible.
I can't see anything like a linear/square relation in fusion reactor design (even accepting that ML's premise of shrinks being linear in time is not a law, just something that sometimes happened, and sometimes didn't...)
That makes it less impressive; any fluorescent-light tube can maintain a stable plasma for years, after all, without even magnetic confinement.
https://www.energy.gov/science/articles/science-close-develo...
>> In the H-mode, a calm edge without turbulence reduces how much heat and how many charged particles the plasma loses. This leads to a sharp increase in pressure across the entire volume of the plasma, including the core where the conditions that can lead to fusion occur. The reduced energy and particle losses also minimize damage to the material surfaces surrounding the plasma.
Suppose we had one prediction market M_1 for “On January 1st 2070, resolves ‘yes’ if there has been a commercially successful nuclear fusion power plant, and otherwise resolves ‘no’”, and then another market M_2 that, maybe it resolves in 5 years as ‘yes’ if the price of M_1’s ‘yes’ is greater than 30%? Or… hm, that seems problematic because people could just buy a bunch of M_1’s “yes” right before M_2 resolves? Or maybe that’s a self-correcting problem because people could… no, still seems like a problem..
Well, what if instead of a prediction market about the future value of another prediction market, it was futures contracts for the shares in a prediction market? Like, the right to buy or sell shares in “yes” or “no” at a particular price?
So like, if you’re confident that the prediction market will assign probability p or higher on a particular day 5 years from now, then if you bought futures which, on that day each of the futures could be used to sell a share in “no” at the price (1-p), then… well, if the probability assigned to “yes” on that day is indeed p or higher, then the price of “no” would be (1-p) or lower, so one buy a share in “no” at a price less than (1-p) and then sell it at (1-p)..
Hm, issue there is one still needs to buy the “no” in order to sell it, so that doesn’t seem to really fix the “what if there is no liquidity in 5 years?” issue?
I guess one could spend 1 to create a share of “yes” and a share of “no”, and then sell the “no”, and be left with the share in “yes” which is ostensibly worth at least p, and then like, sell it a bit later when there’s more liquidity or something?
I probably don’t know what I’m talking about about this.
None of them solve this problem, though:
> Now, of course, one can hope to sell your shares in “yes” or “no” 5 years from now, but there may not be enough liquidity?
In general, if there isn't liquidity in the primary market you should expect the derivative markets to be even worse. You would use options not to find extra liquidity - and binary options on illiquid markets like you describe are indeed particularly prone to market manipulation - but to express very particular views.
> another market M_2 that, maybe it resolves in 5 years as ‘yes’ if the price of M_1’s ‘yes’ is greater than 30%?
Like this one - you should buy this contract if you really do want to make a bet the price will be over 30%, and you don't care much about getting a big payday if the price is 90 or keeping most of your money if the price is 29.
For example, Bill Gates is going to die like everyone else and give most of the money away, like Warren Buffet.
They can spend a significant amount of money in life if they see nuclear fusion is possible, even if they do not recover the costs.
The only thing that is needed for this to happen is investors being confident that the money is not going to be wasted.
I personally know rich people that are betting a significant part of their wealth in fusion(millions USD) even when they know there is a risk that they will never recover the money.
I think there was (maybe still possible?) a real missed opportunity to pitch green energy in a national security or America First way. I don’t think the average republican voter wants us to be as tied to OPEC the way we are.
We could still product as much—or more!—oil in Texas while reducing our care for anything in the Middle East.
This is true of every energy system ever.
The world spends 10% of global GDP on energy, about $10 trillion per year. The world will spend something like a quadrillion dollars on energy this century, possibly more as the world gets wealthier and per capita energy use increases. A billion dollar investment is just one part in a million of that. Fusion doesn't have to be very likely to succeed to make such speculation worthwhile.
I'm not sure how this works, how are they confident enough that they can make it produce net power?
ARC which they announced siting for and is intended to be their first grid-attached net power provider only just had the location selected so I don't believe its got much construction going on yet. The goal for that plant to be producing power is "early 2030s".
They haven't even gotten to Q>1, let alone building a real power plant.
Is this something where it's on the precipice and small tweaks bridges from 22 minutes to basically indefinitely?
These are science machines to learn about plasma and increase performance of future machines. A real reactor involves a lot of engineering to handle the heat rejection problem (and turn it into a revenue stream if you're clever). In terms of the pulsed nature: not really a problem if you keep the duty cycle high enough and maintain sufficient buffers in your coolant to keep the turbines happily turning away.
I've seen photos of what the inside of experimental tokamaks look like after many cycles. Metal is eroded away and deposited around the chamber in interesting patterns. Unfortunately a image search isn't surfacing the images I have in mind.