Nuclear fusion startup raises $100M to design and build a demo power plant(bloomberg.com)
bloomberg.com
Nuclear fusion startup raises $100M to design and build a demo power plant
https://www.bloomberg.com/news/articles/2019-12-16/bezos-backed-fusion-start-up-raises-100-million-for-demo-system
101 comments
This is their design: https://www.youtube.com/watch?v=k3zcmPmW6dE
One would think that if it were so easy, nobody would bother with magnets:
https://en.wikipedia.org/wiki/ITER
"If ITER becomes operational, it will become the largest magnetic confinement plasma physics experiment in use with a plasma volume of 840 cubic meters,[15] surpassing the Joint European Torus by almost a factor of 10."
I fail to find any hint to a reasonable estimation of viability of General Fusion's concept.
Edit: and I mean a written estimation, not that they will now, with the received money, according to their own words, just "formally launch the program" (note they promise just to formally launch the program, nothing more) "to design, construct, and subsequently operate its Fusion Demonstration Plant." Heh.
https://en.wikipedia.org/wiki/ITER
"If ITER becomes operational, it will become the largest magnetic confinement plasma physics experiment in use with a plasma volume of 840 cubic meters,[15] surpassing the Joint European Torus by almost a factor of 10."
I fail to find any hint to a reasonable estimation of viability of General Fusion's concept.
Edit: and I mean a written estimation, not that they will now, with the received money, according to their own words, just "formally launch the program" (note they promise just to formally launch the program, nothing more) "to design, construct, and subsequently operate its Fusion Demonstration Plant." Heh.
> I fail to find any hint to a reasonable estimation of viability of General Fusion's concept.
And hence the reason they are wanting to build a working prototype.
They have a conceptual model that needs to be tested.
And hence the reason they are wanting to build a working prototype.
They have a conceptual model that needs to be tested.
In fact there is something like a dozen groups working on prototypes to do fusion cheaper than ITER. Obviously, the people running ITER don't think that it can be done cheaper. The race is on!
What I don't understand is why the WX-7 looks nothing like ITER. The people putting together WX-7 evidently thought that these convolutions were required, yet the ITER group does not. The race is not simple!
What I don't understand is why the WX-7 looks nothing like ITER. The people putting together WX-7 evidently thought that these convolutions were required, yet the ITER group does not. The race is not simple!
>The people putting together WX-7 evidently thought that these convolutions were required, yet the ITER group does not...
They're just two different ways to solve the same problem. If you confine a plasma in a symmetric toroidal field, the difference in field strength between the inner and outer edges of the torus cause the electrons and protons in the field to separate. This causes a buildup of huge voltages in the plasma, causing a breakdown in the magnetic field.
A stellarator fixes this by twisting the plasma loop into a figure 8 pattern that causes electrons and protons to twist and loop round the plasma path and roughly cancel out the voltages, not quite, but close. A tokamak confines the particles in a torroidal field, but winds the magnetic field lines round the torus in a helical pattern.
They're just two different ways to solve the same problem. If you confine a plasma in a symmetric toroidal field, the difference in field strength between the inner and outer edges of the torus cause the electrons and protons in the field to separate. This causes a buildup of huge voltages in the plasma, causing a breakdown in the magnetic field.
A stellarator fixes this by twisting the plasma loop into a figure 8 pattern that causes electrons and protons to twist and loop round the plasma path and roughly cancel out the voltages, not quite, but close. A tokamak confines the particles in a torroidal field, but winds the magnetic field lines round the torus in a helical pattern.
WX-7:
"purpose is to advance stellarator technology, though this experimental reactor will not produce electricity, it is used to evaluate the main components of a future fusion power plant"
https://en.wikipedia.org/wiki/Wendelstein_7-X
To compare, even ITER, international nuclear fusion research and engineering megaproject, initiated in 1988 (!) will also not produce any electrical energy:
"ITER will not capture the energy it produces as electricity, but—as first of all fusion experiments in history to produce net energy gain—it will prepare the way for the machine that can."
https://www.iter.org/proj/inafewlines
The net energy "gained" in ITER experiment, if it achieves that much, will be just "vented to the atmosphere." The other experiments don't even expect to have any gain.
https://en.wikipedia.org/wiki/ITER
The smallest possible promise is, of course, that the money received "enables the Company to formally launch the program" as in the "news" here:
https://generalfusion.com/2019/12/general-fusion-closes-65m-...
"purpose is to advance stellarator technology, though this experimental reactor will not produce electricity, it is used to evaluate the main components of a future fusion power plant"
https://en.wikipedia.org/wiki/Wendelstein_7-X
To compare, even ITER, international nuclear fusion research and engineering megaproject, initiated in 1988 (!) will also not produce any electrical energy:
"ITER will not capture the energy it produces as electricity, but—as first of all fusion experiments in history to produce net energy gain—it will prepare the way for the machine that can."
https://www.iter.org/proj/inafewlines
The net energy "gained" in ITER experiment, if it achieves that much, will be just "vented to the atmosphere." The other experiments don't even expect to have any gain.
https://en.wikipedia.org/wiki/ITER
The smallest possible promise is, of course, that the money received "enables the Company to formally launch the program" as in the "news" here:
https://generalfusion.com/2019/12/general-fusion-closes-65m-...
>> Obviously, the people running ITER don't think that it can be done cheaper
That's actually not obvious at all. ITER project was started 12 years ago. By now it's very likely that there are ways to do it cheaper. But what do you do? Abandon the partially built ITER and start over? And what do you do if 5 years from now there are ways to build it cheaper still? So the government bureaucracies are marching on to complete it, which IMO is a sensible thing to do. But it doesn't mean it can't be done cheaper or more simply with 2020 technology.
That's actually not obvious at all. ITER project was started 12 years ago. By now it's very likely that there are ways to do it cheaper. But what do you do? Abandon the partially built ITER and start over? And what do you do if 5 years from now there are ways to build it cheaper still? So the government bureaucracies are marching on to complete it, which IMO is a sensible thing to do. But it doesn't mean it can't be done cheaper or more simply with 2020 technology.
For what it's worth, people have been wondering about fusion with sonoluminescence for about 20 years (that I know of) but probably longer:
https://en.wikipedia.org/wiki/Sonoluminescence
Since fluids are approximately incompressible, they can concentrate a tremendous amount of pressure and heat in a small space when rammed together with no route for escape:
https://en.wikipedia.org/wiki/Water_hammer
Since we know that the hydrogen in water will fuse on its own under enough pressure, we can run the calculation using the water hammer formula;
https://en.wikipedia.org/wiki/Solar_core
If we use a length of 1 meter, and velocity of 1 meter per second, we can see what compression time is required to achieve the pressure at the core of the sun using a water hammer:
So this is the maximum time that the liquid must remain compressed at the center without finding a way out (via quantum tunneling or something, who knows at these extremes) in order to reach the desired pressure. I don’t know if the shape of the bubble needs to be spherical or if any geometry works. I also don’t know how temperature affects it (the temperature will likely be higher than for sonoluminescence since the bubble is bigger). But we do know that the general idea works, because fusion bombs are ignited by a fission bomb compressing hydrogen to the necessary heat and pressure.
The main problem will be with the hydrogen plasma diffusing into the metal. But since pressure falls off gradually from the center, the cross section should be large enough that it may not pose much of an issue. I also wonder if the presence of the metal atoms might create smaller channels through which the hydrogen must pass. That would take advantage of the electromagnetic force holding atoms apart, similarly to how magnetic confinement works in a Tokamak or Farnsworth Fusor, and create pinch points where atoms are more likely to fuse.
The final reactor design should probably use liquid hydrogen because a bigger cross section could fuse, because the P=pLv/t formula is linear. F=ma means that lighter atoms accelerate linearly faster under the same force, but also decrease final pressure linearly. So if my math is right, final pressure should be within the same order of magnitude for all atoms (hopefully someone can check this). For example, liquid hydrogen has a density of 0.07 grams per cubic centimeter, so is 14.29 times less dense than water, so the final V for liquid hydrogen should be about 14.29 times higher than water and 14.28 * 11.4 = 162.9 times higher than lead. But final pressure would be 14.29 and 162.9 times lower respectively so result in nearly the same maximum pressure.
Also they should tune the geometry so that the 1 second firing rate matches the bounce frequency of the liquid.
Thermodynamic efficiency probably won’t be great at first, with the Carnot limit of:
https://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodyna...
Maybe the first reactor design gets 10% of unity, maybe the second one gets 20%. It will be interesting to see the final formula for reactor size vs gain factor (Q), because then we’ll know if it can simply be scaled up by a few orders of magnitude or if something in the physics prevents it from working if it’s smaller than a star. Of course this principle is the same for any fusion reactor. Wouldn’t it be wonderful if they find that all that matters is the strength of the pistons and that the reactor can be scaled down to fit in a shipping container, just running at a higher frequency!
My gut feeling is that the General Fusion reactor design is going to work. It will almost certainly achieve fusion (detect neutrons or excess heat) just like with sonoluminescence. Will it be over unity? Well.. I would wager more money on this design than any others that I’ve seen.
https://en.wikipedia.org/wiki/Sonoluminescence
Since fluids are approximately incompressible, they can concentrate a tremendous amount of pressure and heat in a small space when rammed together with no route for escape:
https://en.wikipedia.org/wiki/Water_hammer
Since we know that the hydrogen in water will fuse on its own under enough pressure, we can run the calculation using the water hammer formula;
maximum pressure = 0.0135 * velocity * length / time
https://en.wikipedia.org/wiki/Solar_core
If we use a length of 1 meter, and velocity of 1 meter per second, we can see what compression time is required to achieve the pressure at the core of the sun using a water hammer:
2.65e16 = 0.0135 * 1 * 1 / time
time = 0.0135 * 1 * 1 / 26.5e15 = 5.09e-19 seconds
time = 0.1539 * 1 * 1 / 26.5e15 = 5.81e-18 seconds
time = 0.1539 * 10 * 10 / 26.5e15 = 5.81e-16 seconds
So this is the maximum time that the liquid must remain compressed at the center without finding a way out (via quantum tunneling or something, who knows at these extremes) in order to reach the desired pressure. I don’t know if the shape of the bubble needs to be spherical or if any geometry works. I also don’t know how temperature affects it (the temperature will likely be higher than for sonoluminescence since the bubble is bigger). But we do know that the general idea works, because fusion bombs are ignited by a fission bomb compressing hydrogen to the necessary heat and pressure.
The main problem will be with the hydrogen plasma diffusing into the metal. But since pressure falls off gradually from the center, the cross section should be large enough that it may not pose much of an issue. I also wonder if the presence of the metal atoms might create smaller channels through which the hydrogen must pass. That would take advantage of the electromagnetic force holding atoms apart, similarly to how magnetic confinement works in a Tokamak or Farnsworth Fusor, and create pinch points where atoms are more likely to fuse.
The final reactor design should probably use liquid hydrogen because a bigger cross section could fuse, because the P=pLv/t formula is linear. F=ma means that lighter atoms accelerate linearly faster under the same force, but also decrease final pressure linearly. So if my math is right, final pressure should be within the same order of magnitude for all atoms (hopefully someone can check this). For example, liquid hydrogen has a density of 0.07 grams per cubic centimeter, so is 14.29 times less dense than water, so the final V for liquid hydrogen should be about 14.29 times higher than water and 14.28 * 11.4 = 162.9 times higher than lead. But final pressure would be 14.29 and 162.9 times lower respectively so result in nearly the same maximum pressure.
Also they should tune the geometry so that the 1 second firing rate matches the bounce frequency of the liquid.
Thermodynamic efficiency probably won’t be great at first, with the Carnot limit of:
https://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodyna...
efficiency = 1 - (cold temperature)/(hot temperature)
Maybe the first reactor design gets 10% of unity, maybe the second one gets 20%. It will be interesting to see the final formula for reactor size vs gain factor (Q), because then we’ll know if it can simply be scaled up by a few orders of magnitude or if something in the physics prevents it from working if it’s smaller than a star. Of course this principle is the same for any fusion reactor. Wouldn’t it be wonderful if they find that all that matters is the strength of the pistons and that the reactor can be scaled down to fit in a shipping container, just running at a higher frequency!
My gut feeling is that the General Fusion reactor design is going to work. It will almost certainly achieve fusion (detect neutrons or excess heat) just like with sonoluminescence. Will it be over unity? Well.. I would wager more money on this design than any others that I’ve seen.
After sleeping on this, I realized that even though liquid hydrogen could be the working fluid for the (water) hammer, there would be no way to limit the reaction, so we'd just end up with a hydrogen bomb. I also forgot to include one other link:
https://en.wikipedia.org/wiki/Bubble_fusion
The liquid metal is sort of like the moderator in fission, except in this case it just limits how much hydrogen can fuse by taking the place of the hydrogen in the center.
Also the Carnot efficiency of a liquid hydrogen heat engine would be terrible because it's so cold. It would also be difficult to contain it if it got too hot and turned to gas.
It looks like the compressibility of water is about 46.4 parts per million for every unit increase in pressure:
https://en.wikipedia.org/wiki/Liquid#Volume
And compressibility is roughly inversely proportional to density:
https://en.wikipedia.org/wiki/Compressibility#cite_note-4
Water is 4.6e-10 Pa^-1 and mercury is 3.7×10–11 Pa^-1 so I would guess that the compressibility of liquid lead is comparable to that of mercury.
If we temporarily ignore the compressibility of hydrogen in the center of the bubble, then to find the maximum pressure we'd need to integrate the compression from outside in, based on the kinetic energy of incoming atoms starting from a certain velocity and exerting pressure on the atoms beneath as they come to rest.
Something similar happens in a type II supernova when a large star runs out of fuel and no longer has the heat energy to hold itself up (think of the hot atoms in the core like the gas in a bubble). When the outer layers collapse inward, they form a fluid hammer where the pressure and temperature are so extreme that a large portion of the center of the star fuses all at once.
https://en.wikipedia.org/wiki/Type_II_supernova
I'm having trouble finding a simple formula for the maximum pressure of a collapsing fluid, but this simulation could probably tell us if the General Fusion reactor would actually work:
https://cs.lbl.gov/assets/CSSSP-Slides/20160623-Nonaka.pdf
https://en.wikipedia.org/wiki/Bubble_fusion
The liquid metal is sort of like the moderator in fission, except in this case it just limits how much hydrogen can fuse by taking the place of the hydrogen in the center.
Also the Carnot efficiency of a liquid hydrogen heat engine would be terrible because it's so cold. It would also be difficult to contain it if it got too hot and turned to gas.
It looks like the compressibility of water is about 46.4 parts per million for every unit increase in pressure:
https://en.wikipedia.org/wiki/Liquid#Volume
And compressibility is roughly inversely proportional to density:
https://en.wikipedia.org/wiki/Compressibility#cite_note-4
Water is 4.6e-10 Pa^-1 and mercury is 3.7×10–11 Pa^-1 so I would guess that the compressibility of liquid lead is comparable to that of mercury.
If we temporarily ignore the compressibility of hydrogen in the center of the bubble, then to find the maximum pressure we'd need to integrate the compression from outside in, based on the kinetic energy of incoming atoms starting from a certain velocity and exerting pressure on the atoms beneath as they come to rest.
Something similar happens in a type II supernova when a large star runs out of fuel and no longer has the heat energy to hold itself up (think of the hot atoms in the core like the gas in a bubble). When the outer layers collapse inward, they form a fluid hammer where the pressure and temperature are so extreme that a large portion of the center of the star fuses all at once.
https://en.wikipedia.org/wiki/Type_II_supernova
I'm having trouble finding a simple formula for the maximum pressure of a collapsing fluid, but this simulation could probably tell us if the General Fusion reactor would actually work:
https://cs.lbl.gov/assets/CSSSP-Slides/20160623-Nonaka.pdf
I always had the wrong assumption with General Fusion being privately funded, it was partly owned and invested by General Electric.
Turns out they dont have anything in common apart from the name.
Turns out they dont have anything in common apart from the name.
You will be amazed to learn of the existence of General Motors, General Dynamics (and General Atomics) and General Mills, then, all of which are unrelated to GE.
General Magic, also unrelated to GE: https://en.wikipedia.org/wiki/General_Magic
There's also General Technics, yet to be formed. A nod to whoever remembers that company.
The founder of General Fusion was somebody who lived in the same small island community as me. He's a true hacker. Very eccentric. If I recall correctly, he bought the old gas station which was on the main street of the island and that's where he brought his prototype to life. I think people were surprised to learn that the eccentric mad scientist was working on nuclear experiments next to their homes :)
Which island is it?
according to https://en.wikipedia.org/wiki/Michel_Laberge it is British Columbia.
British Columbia is not an island. The website for General Fusion [0] notes that the island in question is Bowen Island.
[0] https://generalfusion.com/2014/07/from-the-archives-general-...
[0] https://generalfusion.com/2014/07/from-the-archives-general-...
I am not familiar with the area, but according to Google “Bowen Island is Municipality in British Columbia, Canada” .
Forget the power, 1.5GWt plant of this design could make almost 5 party balloons per hour worth of helium!
mev_per_fusion = 17.59e6
mev_per_j = 1.602e-19
pwr_thermal = 1.5e9
j_per_fusion = mev_per_fusion * mev_per_j
fusions_per_second = pwr_thermal/j_per_fusion
l_He_per_second = 22.4 * fusions_per_second / 6.02e23
l_per_ballon = 14.1
ballons_per_hr = (l_He_per_second * 60 * 60)/l_per_ballon
mev_per_fusion = 17.59e6
mev_per_j = 1.602e-19
pwr_thermal = 1.5e9
j_per_fusion = mev_per_fusion * mev_per_j
fusions_per_second = pwr_thermal/j_per_fusion
l_He_per_second = 22.4 * fusions_per_second / 6.02e23
l_per_ballon = 14.1
ballons_per_hr = (l_He_per_second * 60 * 60)/l_per_ballon
I remember my dad saying about ten years ago that we should flatout stop selling helium to the average consumer until we've really cracked fusion. His reasoning was that helium is used in medicine and quantum computing, which has a whole slew of uses, vs a balloon that some kid is going to lose in five minutes anyway.
It would be pretty neat if we made helium a renewable resource, even if it is slow.
It would be pretty neat if we made helium a renewable resource, even if it is slow.
I'd say more helium is generated in the Earth crust than the potential fusion reactors powering all of humanity. Probably by several orders of magnitude.
Just distill it out of the atmosphere before it escapes into space - it'll be only a small order of magnitude more expensive than today's helium.
Just distill it out of the atmosphere before it escapes into space - it'll be only a small order of magnitude more expensive than today's helium.
Forgive me for some ignorance here, since I know almost nothing about nuclear physics or chemistry, but from what I understood, doesn't helium escape out into space? Would there even be any to extract outta the atmosphere?
There is helium in the atmosphere. It is on its way from being created in the crust to escaping into space. But as long as it is in the atmosphere, it could be extracted.
You can make helium with fission, too - in fact that's where almost all of the helium on Earth comes from. Alpha radiation is just a helium nucleus, after all!
I know next to nothing about this. What material is being broken down to create helium?
There are lots of elements that decay by spitting out an alpha particle -- just another name for a helium nucleus.
I am reliably informed that spitting out an He+2 and turning into something chemically other is not fission. Apparently those unstable nuclei that split this way actually had a He nucleus bouncing around in there, and it tunneled out "honestly".
I am reliably informed that spitting out an He+2 and turning into something chemically other is not fission. Apparently those unstable nuclei that split this way actually had a He nucleus bouncing around in there, and it tunneled out "honestly".
I believe two hydrogens are fused together to create a helium.
Isn't it 4 hydrogens? And one of the cool things that happens is 2 of those protons turn into neutrons + positrons.
Fusing 4 protons into helium definitely happens in the sun, where protons are the most common hydrogen isotope. Most fusion on Earth is done using the deuterium-tritium reaction, which produces helium and a neutron. The reason is that it's an easier reaction to do: Obtaining the special hydrogen isotopes is much less of a pain than trying to design a reactor that uses the 4 proton reaction.
No, if I remember correctly the most probable fusion path are deuterium + tritium and deuterium + deuterium.
In both case there are only 2 hydrogen isotopes fusing together, not 4.
ITER has been working on this problem for almost a decade now, and with more money available to them. What are the odds some startup can beat them to the punch?
> ITER has been working on this problem for almost a decade now
ITER has been working on one implementation of magnetic confinement. It's an international effort, bringing to the battle the advantages of scale and disadvantages of multilateral bureaucracy.
Since ITER was formed in 2007 [1], the bleeding edge has advanced beyond Tokomaks. Advanced computational methods birthed the Wendelstein 7-X [2]. Improved superconducting magnets are compacting designs, reducing costs--and thus accessibility to start-ups--through mass reduction.
It's almost likely a start-up beats ITER. And that's fine! I don't know if any of these designs would be where they are if ITER hadn't been funded.
[1] https://en.wikipedia.org/wiki/ITER#Organization_history
[2] https://en.wikipedia.org/wiki/Wendelstein_7-X
ITER has been working on one implementation of magnetic confinement. It's an international effort, bringing to the battle the advantages of scale and disadvantages of multilateral bureaucracy.
Since ITER was formed in 2007 [1], the bleeding edge has advanced beyond Tokomaks. Advanced computational methods birthed the Wendelstein 7-X [2]. Improved superconducting magnets are compacting designs, reducing costs--and thus accessibility to start-ups--through mass reduction.
It's almost likely a start-up beats ITER. And that's fine! I don't know if any of these designs would be where they are if ITER hadn't been funded.
[1] https://en.wikipedia.org/wiki/ITER#Organization_history
[2] https://en.wikipedia.org/wiki/Wendelstein_7-X
You're right about better superconductors leading to more compact and cheaper reactor designs, but many, if not most, of those designs are still tokamaks. To say that the bleeding edge has moved beyond tokamaks is just wrong.
To take your example of Wendelstein 7-X, the only sources I can find give an expected Q factor of 0.1. JET was getting 0.75 ages ago. ITER will hopefully hit 10. While I'm excited about stellarators because they're very interesting to research, they probably won't be catching up to tokamaks any time soon.
To take your example of Wendelstein 7-X, the only sources I can find give an expected Q factor of 0.1. JET was getting 0.75 ages ago. ITER will hopefully hit 10. While I'm excited about stellarators because they're very interesting to research, they probably won't be catching up to tokamaks any time soon.
>ITER will hopefully hit 10.
As a layman, is it right to think that this would mean viable fusion has arrived at that point? I mean, 10x energy out/in is a victory, no? Is there another factor that stops ITER from being immediately used and replicated for energy generation?
As a layman, is it right to think that this would mean viable fusion has arrived at that point? I mean, 10x energy out/in is a victory, no? Is there another factor that stops ITER from being immediately used and replicated for energy generation?
Yes and no.
ITER will be first device to produce more heat energy than put in, but it won't be generating any electricity. [1] It will instead be used to make research on, so we can plan the next project, codenamed DEMO.
DEMO will produce net energy, but still be experimental, for designing final version of a commercial fusion power plant. And that commercial plant is aimed to be working by 2050. [2]
ITER is rather looked upon as risk-free and certain way to fusion, whereas startups... are startups. IMHO, we need both approaches.
Also there are many more fusion startups than General Fusion, here are some to follow:
- Tokamak Energy: https://www.youtube.com/channel/UCuSlFJbBUIj1zfJLRnGXSow - LPP Fusion: https://www.youtube.com/channel/UCiBditpj7sdROMYz02qoCMQ - TAE Technologies: https://www.youtube.com/channel/UC-LHpK7z8vjMq2-pt4wG4ug - Commonwealth Fusion Systems: https://cfs.energy - First Light Fusion: https://firstlightfusion.com
1: https://www.iter.org/proj/inafewlines 2: https://www.iter.org/mag/3/22
ITER will be first device to produce more heat energy than put in, but it won't be generating any electricity. [1] It will instead be used to make research on, so we can plan the next project, codenamed DEMO.
DEMO will produce net energy, but still be experimental, for designing final version of a commercial fusion power plant. And that commercial plant is aimed to be working by 2050. [2]
ITER is rather looked upon as risk-free and certain way to fusion, whereas startups... are startups. IMHO, we need both approaches.
Also there are many more fusion startups than General Fusion, here are some to follow:
- Tokamak Energy: https://www.youtube.com/channel/UCuSlFJbBUIj1zfJLRnGXSow - LPP Fusion: https://www.youtube.com/channel/UCiBditpj7sdROMYz02qoCMQ - TAE Technologies: https://www.youtube.com/channel/UC-LHpK7z8vjMq2-pt4wG4ug - Commonwealth Fusion Systems: https://cfs.energy - First Light Fusion: https://firstlightfusion.com
1: https://www.iter.org/proj/inafewlines 2: https://www.iter.org/mag/3/22
Well, DEMO, the demonstration power station to follow ITER is estimated to have a Q of 25 and output of 2GW. Whether that's viable will then be less about the physics and more about the cost that they can get subsequent designs down to when they have to compete with high capacity factor offshore wind, battery firmed utility solar, pumped hydro, etc. in 2040. It'll be a fascinating engineering challenge. I hope they can make it happen, but I doubt it.
The next big problem after hitting positive energy production will be sustainability. My understanding is that the walls of the reactor get hit with enough stray neutrons that they degrade (often in radioactive ways). Unlike in fission reactors where you can put in a lot of absorptive shielding (like lead), in a fusion reactor you have to keep the magnets close to what they are working on.
Note, I am not talking about really long term radioactive waste here, more like things that are dangerous for less than 100 years. Still problematic, but not for millions of years like fission.
Note, I am not talking about really long term radioactive waste here, more like things that are dangerous for less than 100 years. Still problematic, but not for millions of years like fission.
No. The notion that achieving a certain plasma physics performance means viable fusion has arrived is a very common misconception. It's quite possible that even if the plasma physics problems are well solved, fusion could end up never being viable, for engineering/economic reasons.
As odd as it counts ITER is not about efficiency, it’s more about research into construction and operations.
We could have built a fusion reactor in the 90’s simply scaling up JET, but the amount of power that would be produced was not worth the investment. For example we lack the tritium production to keep up with even a single 1GW fusion reactor let alone a large scale deployment. So, we need to be able to produce it or get by with mostly DD reactions.
That’s just one of thousands of issues being investigated.
We could have built a fusion reactor in the 90’s simply scaling up JET, but the amount of power that would be produced was not worth the investment. For example we lack the tritium production to keep up with even a single 1GW fusion reactor let alone a large scale deployment. So, we need to be able to produce it or get by with mostly DD reactions.
That’s just one of thousands of issues being investigated.
For General Fusion they have a completely different approach. It's not a Tokamak like ITER. It remains to be seen if it works at scale though.
Commonwealth Fusion also thinks they can move faster than ITER with a Tokamak reactor, by utilising new and better superconductors. I suppose the design of ITER was locked down before those became available in large quantities.
Commonwealth Fusion also thinks they can move faster than ITER with a Tokamak reactor, by utilising new and better superconductors. I suppose the design of ITER was locked down before those became available in large quantities.
ITER is taking the safest approach, and being a giant international cooperation makes them probably as flexible and nimble as a boulder. A startup betting on a novel, cheaper approach could beat them as long as they accept a much higher risk of failure. And while a government wouldn't invest $100M in something with say 10% chance of success, compared to $6B for ITER that's a worthwile bet for everyone else
"Safest" here being the approach that physics and enfineering say is most likely to succeed: project risk, not actual safety risk.
(Ironically it was so large that until it shaken up, the project nearly sank for the usual "megaproject drama" reasons)
(Ironically it was so large that until it shaken up, the project nearly sank for the usual "megaproject drama" reasons)
> And while a government wouldn't invest $100M in something with say 10% chance of success, compared to $6B for ITER that's a worthwile bet for everyone else
Maybe governments should. That’s doesn’t seem like a large amount of money in the scheme of things and I’d rather the tech not belong to a startup.
Maybe governments should. That’s doesn’t seem like a large amount of money in the scheme of things and I’d rather the tech not belong to a startup.
In an ideal world, government would invest in many more low-probability/high-impact engineering projects. But this doesn't align well with political incentives - 100M on a bet that will return 50X 10% of the time is great for a private investor, but a politician won't get 50X the votes from a successful project as an unsuccessful one, instead there's a 90% chance the project will be portrayed as a boondoggle.
The problem with investing in a lot of low probability things is that when, say, 100 of them all fail, how do you know whether that's because they were low probability, or zero probability? Unfortunately, there's no limit to the number of very low probability things you can invest in, so nobody has the budget for them all.
it's also not ideal for government to make those sorts of bets, because they is no reasonable incentive structure for the government to 1) find the talent to make correct bets about those sorts of things and 2) to be accountable in case the person making those bets is just an garden variety idiot, or, worse, taking the government for a ride.
Also, those relatively small investments of $100M will add up to a lot over time. At some point people are going to get a bit sour on the idea of acting like an angle investor with tax dollars.
Why does it matter if the tech belongs to a startup? If any of these projects ever actually works, 1) they're still going to be very capital-intensive, and 2) it's still going to be a private company that builds the production plants. Patent exclusivity only lasts a couple of decades anyway, so personally I'd rather go with whatever approach gets us commercial fusion power in my lifetime.
I’m a firm believer that any sort of fundamental research and their outcomes should be owned by the public. We may have to contract a company to build the thing, but the knowledge should be free for all.
Then what incentive is there for investment into R&D if it doesn’t give a competitive advantage? Patents are designed to encourage investment by providing a monopoly for an exclusive time only - we can debate how long that should be - but the fundamental fact is that without patents innovation slows greatly
I agree. I wonder though how these kinds of funding decisions could be made without too much money just funneled to friends of the reviewers pet projects. Its not like you can just put out a bid for cheap fusion and award the lowest bidder.
I think another factor is that it is much harder to defend high risk investment from corruption and cronyism.
I'll link to the NAS report on fusion findings. US benefits from ITER partnerships work both ways. But also recommends investments in smaller, less expensive, more innovative (and therefore competitive) designs.
http://www8.nationalacademies.org/onpinews/newsitem.aspx?Rec...
Just to put things in perspective. ITER budget is estimated ~$25B. Seeking to produce >500MW with a 12T magnetic field. Massive radius. Twice any previous tokamak size. Just look at the pictures ;)
JET budget was ~$5B total. And achieved 25MW with a 5T coil. But without actually "burning plasma" (Max Q < 1.0)
Princeton Plasma Physics Lab run by DoE budget is >$100M per annum. So this represents a significant challenge, and not just in fund raising.
The most promising space might be in the design of "mini-magnets"
https://nationalmaglab.org/news-events/news/lbc-project-worl...
http://www8.nationalacademies.org/onpinews/newsitem.aspx?Rec...
Just to put things in perspective. ITER budget is estimated ~$25B. Seeking to produce >500MW with a 12T magnetic field. Massive radius. Twice any previous tokamak size. Just look at the pictures ;)
JET budget was ~$5B total. And achieved 25MW with a 5T coil. But without actually "burning plasma" (Max Q < 1.0)
Princeton Plasma Physics Lab run by DoE budget is >$100M per annum. So this represents a significant challenge, and not just in fund raising.
The most promising space might be in the design of "mini-magnets"
https://nationalmaglab.org/news-events/news/lbc-project-worl...
How can one presume that the multi-national, highly political, very long term ITER program is the definitive source of truth?
technically, they are persuing a completely different mechanism. In my opinion it's totally bonkers, but in principle there is no reason why the spend/return should be correlated.
Happens all the time with other kinds of startups. The main thing with this is having a good skillset and a good idea.
A good skillset and a good idea is the "main thing" if you want to make a software product.
What you need with fusion is fundamentally new science, not just an idea to pound into shape. That's rather a taller order than a disruptive crowd-scale gig play in the power industry.
What you need with fusion is fundamentally new science, not just an idea to pound into shape. That's rather a taller order than a disruptive crowd-scale gig play in the power industry.
Well, GF is using a liquid metal liner to compress their plasma: https://www.youtube.com/watch?time_continue=77&v=k3zcmPmW6dE...
Oddly, I remember a UFO TV show describing the alien powerplant as relying on liquid metal in some way. No idea if that is meaningful.
Oddly, I remember a UFO TV show describing the alien powerplant as relying on liquid metal in some way. No idea if that is meaningful.
I used to have a favorable impression of what General Fusion was doing.
Their approach addressed one of the big engineering problems facing fusion: have materials that can withstand the power/area across the surface of the reactor, and particularly stand up to neutron and energetic charged particle bombardment of the reactor structure.
Their first approach involved putting a plasmoid (spheromak, as I recall) in a cavity in a bath of liquid metal (lithium say), then launching a focused shock wave inward to compress the cavity and the plasma to very high density. There would be no solid reactor component exposed to the radiation from the plasma (a thick layer of liquid lithium would be interposed in all directions), and the peak pressure could be much higher than structural materials could withstand (because the compression and reaction would occur on time scale short compared to the time required for a sound wave to propagate across the liquid.)
But it turned out this approach was fatally flawed.
While they had trouble with confinement, the big problem is that to get that fast a reaction, very high density, and therefore very strong magnetic fields (magnetic pressure goes as magnetic field squared) would be required. Peak fields in their first approach would be as high as 700 T. But this would imply very large currents would be flowing in the liquid metal compressing the magnetized plasma. Beyond ~100 T, these current would be so strong that the surface of the metal would be vaporized, and non-conducting metal vapor would flow into and quench the plasma. Game over.
So, they've gone to a slow scheme. The implosion is now subsonic, and also there's a metal post running down the center of the chamber to increase stability. But this ruins the main attractive feature of their concept. That metal post will be subject to orders of magnitude higher average neutron flux than the walls of typical fusion concepts, and will also be crushed with magnetic pressure from 100 T magnetic fields. The engineering to make this work would be beyond heroic. The subsonic compression also means the entire reactor vessel will experience very high pressures, even if the rest of it is shielded from the radiation.
Their approach addressed one of the big engineering problems facing fusion: have materials that can withstand the power/area across the surface of the reactor, and particularly stand up to neutron and energetic charged particle bombardment of the reactor structure.
Their first approach involved putting a plasmoid (spheromak, as I recall) in a cavity in a bath of liquid metal (lithium say), then launching a focused shock wave inward to compress the cavity and the plasma to very high density. There would be no solid reactor component exposed to the radiation from the plasma (a thick layer of liquid lithium would be interposed in all directions), and the peak pressure could be much higher than structural materials could withstand (because the compression and reaction would occur on time scale short compared to the time required for a sound wave to propagate across the liquid.)
But it turned out this approach was fatally flawed.
While they had trouble with confinement, the big problem is that to get that fast a reaction, very high density, and therefore very strong magnetic fields (magnetic pressure goes as magnetic field squared) would be required. Peak fields in their first approach would be as high as 700 T. But this would imply very large currents would be flowing in the liquid metal compressing the magnetized plasma. Beyond ~100 T, these current would be so strong that the surface of the metal would be vaporized, and non-conducting metal vapor would flow into and quench the plasma. Game over.
So, they've gone to a slow scheme. The implosion is now subsonic, and also there's a metal post running down the center of the chamber to increase stability. But this ruins the main attractive feature of their concept. That metal post will be subject to orders of magnitude higher average neutron flux than the walls of typical fusion concepts, and will also be crushed with magnetic pressure from 100 T magnetic fields. The engineering to make this work would be beyond heroic. The subsonic compression also means the entire reactor vessel will experience very high pressures, even if the rest of it is shielded from the radiation.
It will be interesting to see where this is based, and I am wondering if it will partly be in Singapore. Singapore sovereign wealth fund Temasek led the funding, and Prime Minister Lee Hsien Loong’s wife Ho Ching serves as the chief executive.
General Fusion is based in British Columbia.
Given the size of Singapore, I think you are far better off with the research facility safely nestled in some corner of British Columbia rather than in your back yard.
Fusion reactors should be fairly safe, no chance of an explosion or meltdown or whatever AFAIK.
During testing I suppose things could go wrong, but they’d probably be barking up the wrong tree then.
During testing I suppose things could go wrong, but they’d probably be barking up the wrong tree then.
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Given $b investment opportunities, $m investment makes me think this remains long-range, high risk research. I don't see this as evidence "fusion on earth for power is now real"
Whats real, is that a lot of money is sloshing around in the hands of people who are more motivated to put it into this kind of venture, than before. Space sucked up some of it, but now space is proven to be a viable investment choice, higher risk money has to look somewhere else.
Whats real, is that a lot of money is sloshing around in the hands of people who are more motivated to put it into this kind of venture, than before. Space sucked up some of it, but now space is proven to be a viable investment choice, higher risk money has to look somewhere else.
How do people think nuclear fusion will affect renewable energies when it comes to maturity? Does this technology make solar and wind some what redundant?
Fusion is more expensive to construct reactors for, but once we have figured out how to do it, the cost will go down rapidly. The fuel for reactors is abundant and cheap, it would effectively end producing power by digging up minerals of any type.
Renewable energies will probably survive for a while but eventually it'll be all fusion. In my opinion, the production of fusion energy will be so cheap that it would be more cost effective to just dump the energy, hence the spikes in power consumption can be compensated by running more reactors and dumping the excess.
Renewable energies will probably survive for a while but eventually it'll be all fusion. In my opinion, the production of fusion energy will be so cheap that it would be more cost effective to just dump the energy, hence the spikes in power consumption can be compensated by running more reactors and dumping the excess.
Why do you think the cost will go down rapidly? Fusion reactors are going to be very big, much bigger than fission reactors of the same power output, and also much more complex. Where does this expectation of them being cheap come from?
They are big and expensive now. If they prove themselves then the economics of scale apply and the price goes down. And of course a lot more funding in the sciences to figure out how to make them cheaper because there is more economic interest.
The problem is, the exact same argument can be applied to all the things fusion would be competing against. In engineering, unlike children in Lake Woebegone, it's not possible for all competitors to come out on top.
To put it another way, the same argument you're making could be applied to (say) making computers from vacuum tubes, or balloons out of lead, or any of a myriad of approaches to solving problems that are losers regardless of effort expended. Why are we assuming fusion isn't also similarly a loser?
To put it another way, the same argument you're making could be applied to (say) making computers from vacuum tubes, or balloons out of lead, or any of a myriad of approaches to solving problems that are losers regardless of effort expended. Why are we assuming fusion isn't also similarly a loser?
There is a stark difference; the fuel for fusion reactors is the most common element in the universe. And literally every other energy source derives it's energy from fusion byproducts.
But this is no argument either. It's like arguing "vacuum tube computers have the advantage that they have no moving parts. And all other computer technologies use the electrons that are manipulated in vacuum tubes."
All that could be true, and fusion could still be hopelessly uncompetitive. The problem is the complexity, difficulty, and size of fusion reactors. Free fuel doesn't make up for that. All the long term beyond-fossil fuel competitors fusion has to beat are also only loosely constrained by fuel availability.
All that could be true, and fusion could still be hopelessly uncompetitive. The problem is the complexity, difficulty, and size of fusion reactors. Free fuel doesn't make up for that. All the long term beyond-fossil fuel competitors fusion has to beat are also only loosely constrained by fuel availability.
Well, I would disagree, the computer comparison doesn't really hold since normal computers don't have a limited and localized supply of electrons (unless they are a laptop). It's more like arguing that a modern 4U Server has more performance than a laptop, really. Which is true.
Fusion reactors might be complex and difficult to figure out, but once it has been figured out the free market will inevitably make it cheaper.
Fuel availability is indeed a problem, IIRC the uranium reserves will hold us out for another 200 years before running out. At current energy demands. So realistically more like 100 years. Coal and oil will inevitably run out too. Sun and Wind don't produce a lot of power compared to Fusion when considering the rare earths required for the components. Fusion is just a lot more efficient and energy rich.
Fusion reactors might be complex and difficult to figure out, but once it has been figured out the free market will inevitably make it cheaper.
Fuel availability is indeed a problem, IIRC the uranium reserves will hold us out for another 200 years before running out. At current energy demands. So realistically more like 100 years. Coal and oil will inevitably run out too. Sun and Wind don't produce a lot of power compared to Fusion when considering the rare earths required for the components. Fusion is just a lot more efficient and energy rich.
The analogy of course wasn't exact, but it fits the structure of your argument, so it shows your argument was wrong.
Fuel availability is NOT a problem. There is no shortage of sunlight, or wind, or uranium (if used in breeder reactors, and why are fusion reactors, which are breeders, allowed but fission breeders are not?) The 200 year figure for uranium assumes a once-through cycle. In breeders, ores with 50-100x less uranium per unit mass of ore would be usable, because breeder get so much more energy out of each unit of uranium mined.
Oh, and please don't repeat the Rare Earth canard. Solar doesn't use rare earths, and wind doesn't have to. I think you're just repeating talking points you haven't bothered to understand.
Fuel availability is NOT a problem. There is no shortage of sunlight, or wind, or uranium (if used in breeder reactors, and why are fusion reactors, which are breeders, allowed but fission breeders are not?) The 200 year figure for uranium assumes a once-through cycle. In breeders, ores with 50-100x less uranium per unit mass of ore would be usable, because breeder get so much more energy out of each unit of uranium mined.
Oh, and please don't repeat the Rare Earth canard. Solar doesn't use rare earths, and wind doesn't have to. I think you're just repeating talking points you haven't bothered to understand.
Nah, the excess will be used for desalination; especially in parts of the world where potable water is less abundant
Fusion will have no effect whatsoever, even if it is made to "work". The cost will be exorbitant.
It it's cheap, sure.
It's probably not going to be that cheap, so it will instead replace all that fossil power.
Renewables are also quick to scale out, and low impact to decommission, so there's no loss in keeping on accelerating wind farm deployment.
It's probably not going to be that cheap, so it will instead replace all that fossil power.
Renewables are also quick to scale out, and low impact to decommission, so there's no loss in keeping on accelerating wind farm deployment.
Fusion will probably be more expensive, but provide a consistent base supply.
I hope they can get $100M of power out of it before they have to decommision and bury the whole thing.
Doesn't seem likely, though.
Doesn't seem likely, though.
Offtopic, sorry: How does everyone read these paywalled articles? Surely you all dont subscribe to bloomberg?
Disable javascript or use a browser that doesn't run it. I am an emacs user so its browser, eww, works for me.
NoScript is a great addition to Firefox. I kept reading recommendations for it and when I finally installed it I wondered why I'd waited so long.
In iOS you can make use of Reader mode, just click on the Hamburger-like icon to the left side of the URL.
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A very well timed press of the escape key, between when the text has started booting and the paywall has started booting. You do it earlier than you'd think.
They really need to get one giant paywall, It doesn't make sense to subscribe to 15 different sources for $300/month
I don't understand why they need to raise money if it's backed by Bezos?
Lots of companies are backed by billionaires and still have many investors.
Sounds like a great way to make disillusioned physicists for the financial industry.
So, a win then. It's like using a fusor[0] not for energy (it can't produce excess energy) but for neutrons. But instead of a physical process, it's an education process. And instead of producing happy physicists it might produce well-paid quants. Awesome!
“If it sounds too good to be true, it’s probably a scam.”
- src: My cooperation’s IT scam awareness flyers
To underscore how challenging magnetic fusion is, here is a thought experiment: imagine you have a ring collider system that collides d with t at the energy which maximizes the probability of fusion. Assume the ions circulate with 0 energy loss except by colliding with the other species of ions. When an ion loses energy in this way, assume its kinetic energy is immediately restored with perfect efficiency. Assume fusion energy is recovered with 100% efficiency. Even with this super idealized head-on collision setup you wouldn't recover enough fusion energy to power the accelerator.
That doesn't really help me understand how challenging it is.
You say that a ring collider would be useless as a fusion energy source. I've never heard of a proposal to use a ring collider to create fusion energy, they're for investigating particle physics.
So I'm left none the wiser - what am I missing?
You say that a ring collider would be useless as a fusion energy source. I've never heard of a proposal to use a ring collider to create fusion energy, they're for investigating particle physics.
So I'm left none the wiser - what am I missing?
> imagine you have a ring collider system
I'm pretty sure you already lost most people here that isn't a physicist.
I'm pretty sure you already lost most people here that isn't a physicist.
Imagine you have a giant magnet and using it makes you lose money.
Where are you losing power from then, bremsstrahlung?
This assumess brem from the ring itself is negligible. Energy loss is from any interaction between ions that doesnt result in fusion. This includes stuff that would scatter ions out of the beam in reality, but in the charitable model its assumed their momenta are immediately reset to the most desirable value with perfect efficiency. In reality this would not be possible due to phase space considerations (Liouville theorem)
The whole article is just about this press release:
https://generalfusion.com/2019/12/general-fusion-closes-65m-...
“General Fusion Closes $65M of Series E Financing“