9 ms·
Progress toward fusion energy gain as measured against the Lawson criteria
- actinium226 1y agoWhy is the last plot basically empty between 2000 and 2020? I understand that NIF was probably being built during that time, but were there no significant tokamak experiments in that time?
- 7thaccount 1y agoI imagine a 20 year gap isn't too crazy for a field like fusion, but you've made me curious as well.
- tomnicholas1 1y agoPresumably because everyone in MCF has been waiting for ITER for decades, and JET is being decommissioned after a last gasp. Every other tokamak is considerably smaller (or similar size like DIII-D or JT-60SA). Much of the interesting tokamak engineering ideas were on small (so low-power) machines or just concepts using high-temperature superconducting magnets.
- moffkalast 1y agoIt's hard to believe that after all of this time, ITER is still almost a decade away from first plasma. There's the common joke that fusion is always 30 years away, but now with the help of ITER, it's always 10 years away instead.
- tomnicholas1 1y agoThe really depressing part is if you plot rate of new delays against real time elapsed, the projected finishing date is even further. This is why much of the fusion research community feel disillusioned with ITER, and so are more interested in these smaller (and supposedly more "agile") machines with high-temperature superconductors instead.
- cyberax 1y agoThe ITER is in development hell. Mind you, it's not useless! It produced a TON of very useful fusion research: neutral beam injectors, divertors, construction techniques for complex vacuum chambers, etc. At this point, I don't think it's going to be complete by the time its competitors arrive. One spinoff of this is high-temperature superconductor research that is now close to producing actually usable high-TC flexible tapes. This might make it possible to have cheaper MRI and NMR machines, and probably a lot of other innovations.
- pfdietz 1y agoITER doesn't use high temperature superconductors. It uses niobium-tin and niobium-titanium low temperature superconductors in its magnets. ITER has been criticized since early days as a dead end, for example because of its enormous size relative to the power produced. A commercial follow-on would not be much better by that power density metric, certainly far worse than a fission reactor. There is basically no chance than a fusion reactor operating in a regime similar to ITER could ever become an economical energy source. And this has been known since the beginning. I call things like ITER "Blazing Saddles" projects. "We have to protect our phony baloney jobs, gentlemen!"
- robocat 1y ago> phony baloney jobs I looked hopefully at the HR report https://www.iter.org/sites/default/files/media/2024-11/rh-2023-okweb.pdf https://www.iter.org/sites/default/files/media/2024-11/rh-20... to see if there was some sort of job categorisation - scientist, engineer, management. Disappointingly scant. PhD heavy. Perhaps the budget would be more insightful. "Execution not ideas" is a common refrain for startups. I wonder how much of the real engineering for ITER is occurring in subcontractors?
- whatshisface 1y agoI wonder why a physics research facility would be PhD-heavy. ;-)
- cyberax 1y ago
- sam 1y agoAuthor here - some other posters have touched on the reasons. Much of the focus on high performing tokamaks shifted to ITER in recent decades, though this is now changing as fusion companies are utilizing new enabling technologies like high-temperature superconductors. Additionally the final plot of scientific gain (Qsci) vs time effectively requires the use of deuterium-tritium fuel to generate the amounts of fusion energy needed for an appreciable level of Qsci. The number of tokamak experiments utilizing deuterium tritium is small.
- CGMthrowaway 1y agoIf ITER is where it's at why are we building commercial scale tokamak? https://en.wikipedia.org/wiki/Commonwealth_Fusion_Systems https://en.wikipedia.org/wiki/Commonwealth_Fusion_Systems
- sam 1y agoCompanies like Commonwealth Fusion Systems are an example of those utilizing high-temperature superconductors which did not exist commercially when ITER was being designed.
- twothreeone 1y agoITER uses HTSs, just not for the coils: > The design operating current of the feeders is 68Ka. High temperature superconductor (HTS) current leads transmit the high-power currents from the room-temperature power supplies to the low-temperature superconducting coils 4K (-269°C) with minimum heat load. Source: https://www.iter.org/machine/magnets https://www.iter.org/machine/magnets
- stshank 1y agoHTS current feeds are a good idea (we also use them at CFS, my employer: https://www.instagram.com/p/DJXInDUuDAK/ https://www.instagram.com/p/DJXInDUuDAK/). It's HTS in the coils (electromagnets) that enables higher magnetic fields and thus a more compact tokamak.
- edran 1y agoThis is a great update! I hope the authors continue publishing new versions of their plots as the community builds up towards facility gain. It's hard to keep track of all the experiments going on around the world, and normalizing all the results into the same plot space (even wrt. just triple product / Lawson criteria) is actually tricky for various reasons and takes dedicated time. Somewhat relevant, folks here might also be interested in a whitepaper we recently put up on arXiv that describes what we are doing at Pacific Fusion: https://arxiv.org/abs/2504.10680 https://arxiv.org/abs/2504.10680 Section 1 in particular gives some extra high-level context that might be useful to have while reading Sam and Scott's update, and the rest of the paper should also be a good introduction to the various subsystems that make up a high-yield fusion demonstration system (albeit focused on pulser-driven inertial fusion).
- arghandugh 1y ago[flagged]
- fecal_henge 1y agoI see you're in the coolant business
- arghandugh 1y ago[flagged]
- BizarroLand 1y agoReal talk, the point is not that whatever system is first past the post for fusion becomes the gold standard and fills the planet. The issue right now is cracking the code. Once that is done, performance gains and miniaturization can take place. Fusion can work on lots of things. Its possible that a fusion system the size of a car could be made within 25 years of the code being cracked that would power a house, or the size of a small building that could power a city block. The waste product of hydrogen fusion is helium, a valuable resource that will always be in high demand, and it will not be radioactive. And yes, it will need coolant as with hot fusion the system uses the heat to turn a turbine, but that coolant isn't fancy, it's just water. Fusion has the potential to solve more problems than it causes by every metric as long as it is doable without extremely limited source materials, and this is what these big expensive reactors are trying to solve.
- arghandugh 1y agoYou’ve disputed nothing I’ve said and unless a dramatically higher temperature fusion reaction that does not generate a neutron flux is achieved, it will generate radioactive waste as a matter of factual physics. Thank you though!
- BizarroLand 1y agoI mean, yes, you're right, but it's not a permanently radioactive waste. Quote: A fusion power plant produces radioactive waste because the high-energy neutrons produced by fusion activate the walls of the plasma vessel. The intensity and duration of this activation depend on the material impinged on by the neutrons. The walls of the plasma vessel must be temporarily stored after the end of operation. This waste quantity is initially larger than that from nuclear fission plants. However, these are mainly low- and medium-level radioactive materials that pose a much lower risk to the environment and human health than high-level radioactive materials from fission power plants. The radiation from this fusion waste decreases significantly faster than that of high-level radioactive waste from fission power plants. Scientists are researching materials for wall components that allow for further reduction of activation. They are also developing recycling technologies through which all activated components of a fusion reactor can be released after some time or reused in new power plants. Currently, it can be assumed that recycling by remote handling could be started as early as one year after switching off a fusion power plant. Unlike nuclear fission reactors, the long term storage should not be required. https://www.ipp.mpg.de/2769068/faq9 https://www.ipp.mpg.de/2769068/faq9 Basically, whatever containment vessel becomes standard for the whole fusion industry would need probably an annual cycle of vessel replacements, which would be recycled indefinitely and possibly mined for other useful radioactive byproducts in the process.
- deleted 1y ago[deleted]
- CGMthrowaway 1y agoI heard that NIF was never intended to be a power plant, not even a prototype of one. It's primarily a nuclear weapon research program. For a power plant you would need much more efficient lasers, you would need a much larger gain in the capsules, you would need lasers that can do many shots per second, some automated reloading system for the capsules, and you would need a heat to electricity conversion system around the fusion spot (which will have an efficiency of ~1/3 or so). Any truth to that?
- ashoeafoot 1y agoIts a fusion & fission scientist storage facility .
- DennisP 1y agoIt's an experimental facility. Yes, a power plant would need much more efficient lasers, but NIF's lasers date back to the 1990s, equivalent modern lasers are about 40X more efficient, and for an experiment it's easy enough to do a multiplication to see what the net result would have been with modern lasers. Modern lasers can also repeat shots much more quickly. Power gain on the capsules appears to scale faster than linear with the input power, so getting to practical gain might not be as far off as it appears at first glance. These are some of the reasons that various fusion startups are pursuing laser fusion for power plants.
- hinkley 1y agoI was trying to work out a joke about buying better lasers off of alibaba but it seems that despite being 30 years old they're still orders of magnitude beyond off the shelf options.
- trhway 1y agopartially. The very efficient lasers from alibaba don't have short pulse/high power, so they can potentially be used only as the part of the system - the pumping lasers. The final nanosecond-laser is still a one-off build which though seems to be pretty doable even by a small company if they set their mind to it. Btw, NIF achieved those recent results by adding strong magnetic field around the target (penny-shrinkers knew that tech for 20+ years :). There are other things like this around that can potentially be similarly useful. Only if somebody had money and interest ...
- UltraSane 1y agoThe money being spent on fusion should be being spent building next generation fission power plants and liquid salt reactors.
- sneak 1y agoWhat's the ROI on that versus current and near-term expected pricing for solar+storage? Is fission getting safer/cheaper at the same rate that solar and batteries are?
- greenavocado 1y agoI wonder if it would make sense to make ultra heavy spent nuclear fuel into gigantic flywheels for short-term grid energy storage
- myrmidon 1y agoNo. Because flywheels are not limited by material density, they are limited by centrifugal force. High density is actively bad, you want to maximize strength and minimize density for flywheel designs, and this makes you much more likely to end up with low density composites (rather than high density tungsten alloys or somesuch).
- UltraSane 1y agoSolar + days of storage is far more expensive than fission. Grid scale batteries like California has spent billions on only have 4 hour capacity. Fission can also supply heat that is needed for many industrial processes and chemical reactions.
- Calwestjobs 1y agoit is not in most us areas. only problem is area covered, NOT price of technology. solar with 12 hour of storage was lower price than fission before covid hit. TCO, not one time nonsense. fission has relatively low temperature heat, i.e. no metal reduction, no "concrete" production. you can cook hot dogs with it. also electrification of heat can provide lower losses stemming from regulation or lack thereof. with electricity you can say i need 293.5 degrees C and you just type it somewhere and you get it for almost free (regulation).
- dale_glass 1y agoIt should be noted that "breakeven" is often misleading. There's "breakeven" as in "the reaction produces more energy than put into it", and there's breakeven as in "the entire reactor system produces more energy than put into it", which isn't quite the same thing.
- analog31 1y agoIn the laser business, the latter is called "wall plug efficiency," which is laser power out per electrical power in.
- westurner 1y ago"Uptime Percentage", "Operational Availability" (OA), "Duty Cycle" Availability (reliability engineering) https://en.wikipedia.org/wiki/Availability https://en.wikipedia.org/wiki/Availability Terms from other types of work: kilowatt/hour (kWh), Weight per rep, number of reps, Total Time Under Tension
- kristianp 1y agoThe article uses the term "scientific breakeven" which I assume is the first one you've stated.
- gosub100 1y agoEspecially since steam turbines are in the 30-40% efficiency range
- russdill 1y agoIt's always confused me a bit. It's not like if you put 10kWh into the reactor, that 10kWh goes away. You still lose a significant fraction of it in inefficiency of the cycle but it still goes towards heat which can be used to heat steam and turn a turbine. iirc, you can get about 4kWh back. On the other side of the coin, if you put 10kWh in and get 10kWh of fusion out, that's 20kWh to run a steam turbine, which nets you about 8kWh. So really you need to be producing 15kWh of heat from fusion for every 10kWh you put in to break even.
- NervousRing 1y agoI've heard of q-plasma and q-total. What is q-science?
- sam 1y agoIt’s the ratio of fusion energy released to heating energy crossing the vacuum vessel boundary.
- gene-h 1y agoThis will probably need to be updated soon. There are rumors NIF recently achieved a gain of ~4.4 and ~10% fuel burn up. Being able to ignite more fuel is notable in and of itself.
- Calwestjobs 1y agowhat "gain" means.
- gene-h 1y agoEnergy out/energy into capsule
- sam 1y agoIn the context implied above it is the ratio of fusion energy released to laser energy on target or the laser energy crossing the vacuum vessel boundary (they are the same in this case). So it would have been more precise to say "target gain" or "scientific gain".
- damnitbuilds 1y agoHmm. How much of this progress is really progress to actual useful fusion power ? I want to believe, but this does not make that easier.
- stshank 1y agoProgress toward net fusion energy is critical for delivering fusion power on the grid. It's not the only progress required — the rest of the machine has to be economical to build and operate. Most of the fusion machines in this paper are scientific projects, but as commercialization progresses, fusion machines with power plant needs in mind should arrive. (I work for one startup in the field, Commonwealth Fusion Systems. We're building our SPARC tokamak now to demonstrate net energy gain in a commercially relevant design.)
- damnitbuilds 1y agoI wish you luck !
- jamiek88 1y agoI’m excited about the new Squids design from the max Planck institute, it’s a design using the lessons learned from the existing stellarator the W7x.
- londons_explore 1y agoAre there any betting odds on "On-Earth Fusion makes up more than 1% of the world energy supply by 2100?"
- sien 1y agoMetaculus sort of does this. The mean prediction is 2046. https://www.metaculus.com/questions/9464/nuclear-fusion-power-01-of-global-energy/ https://www.metaculus.com/questions/9464/nuclear-fusion-powe...
- 0xbadcafebee 1y agoAmazing! Commercial fusion energy is only 30 years away. (it's been 30 years away for 50 years already, but as long as I'm not dead 30 years from now, it's still a good investment...)
- tim333 1y agoOr maybe 10 https://news.mit.edu/2024/commonwealth-fusion-systems-unveils-worlds-first-fusion-power-plant-1217 https://news.mit.edu/2024/commonwealth-fusion-systems-unveil...
- deadbabe 1y agoIf you don’t need a mobile power plant why bother with fusion power instead of something like geothermal? At the end of the day we’re just turning water into steam.
- Calwestjobs 1y agono variant of fusion power is smaller than current coal plant.
- User23 1y agoFusion race vs space race is rather interesting.
- mapt 1y agoAnyone have any idea where First Light Fusion's third machine fits into this? The idea of using literal guns (gunpowder, then light gas gun, then coil gun) to impact projectiles against each other seemed like it was probably ludicrous, but I haven't seen any critical media or numbers yet.
- chuckleMuscle 1y agoFLF's own numbers on this are given in a white paper [1, fig 7.]. Note the "fusion measured" datapoint used a gas gun, rather than Machine-3, as the driver... [1] https://firstlightfusion.com/wp-content/uploads/2024/08/first_light_fusion_triple_product_white_paper.pdf https://firstlightfusion.com/wp-content/uploads/2024/08/firs...
- wonderwonder 1y agoSo much happening in energy right now. If I was to do it again I would have focused on this industry.