MiHoYo, the developer of Genshin Impact, has led a $65m funding round in Shanghai based Energy Singularity which is a company involved in nuclear fusion technology, tokamak devices and operational control systems.

The company plans to build its own Tokamak device by 2024.

https://x.com/ZhugeEX/status/1497957735337443331

I only realized this myself decades after using the term factoid due to pages in highlights for kids.

may or may not be true.

Wikipedia has it as "an item of unreliable information that is repeated so often that it becomes accepted as fact." after the original USofAmerica coinage by Norman Mailer.

In Commonwealth countries (Australia, Canada, UK) two decades past we used it on intelligence forums as the name for atomic snippets of information released by companies via stock exchanges, company reports, PR .. each nugget being an atomic fact like paragraph linked back to a source that asserted that fact to be true, but to be taken as potentially incorrect.

The intended meaning by Norman Mailer never took on in the states.

> In British English a “factoid” is something that looks true but isn't.

I responded that

In British English a “factoid” is something that looks true but may or may not be true.

.. there's a difference.

Jokes aside, what do we actually do in this scenario, when the same word has opposite meanings?

In my opinion, it’s always best to err on caution and use another word if possible (“short fact” instead?).

Because I have seen this factoid discussion before…

Language is the shared meaning between people, so if lots of people understand something the same way… then thats what the word means now

In the same way that if you want to predict which authors will be well known in 400 years, your best bet is on authors that we currently know from 400 years ago. Better to bet on Shakespeare and Aristotle, than e.e.cummings and T.S. Eliot

A word coined in the 1970s won’t be nearly as entrenched in its meaning with the public as an older word.

So, that’s my suspicion. New words are more prone to drift than old words

My first test for Chinese success is "would this have been legal in the US?". I'm not sure who regulates tokamaks but I assume they have a similar risk profile to nuclear reactors (nuclear process releases a vast amount of energy in a tiny space) and so it would be normal if building one commercially was prohibited.

EDIT: If you shot a hole in a fusion reactor, the cold air would immediately quench the plasma down to room temperature.

https://www.fusionindustryassociation.org/nrc-decision-separ...

Supporting letter from Helion Energy: https://www.nrc.gov/docs/ML2224/ML22243A083.pdf

In theory a fusion plant can use the neutrons to irradiate the right chemical element to produce Plutonium-239 or Uranium-233.

  It has been estimated that each 14.1 MeV fusion neutron could be used to produce up to 0.64 plutonium or 233U atoms [4] assuming a TBR of 1.06. This corresponds to 2.85 kg plutonium per MW-year of DT fusion power production, assuming that all of the neutrons are captured in the blanket.

Fusion bombs requires fission bombs as a fuse to have enough heat to explode, fusion reactors wont even come close to that.

Tesla was more than willing to jack up their prices and maximize profit when they could. What drove prices down on Teslas was real competition from the incumbent manufacturers. And inflation cooling people's willingness to blow a bunch of money on expensive cars. And CATL making batteries less expensive. And even then, their cars are only at parity right about now, with a $7500 tax credit. And also only if you are fairly loose about what features you need to consider 'parity' achieved.

OpenPilot works well in limited scenarios, but even the founder George Hotz openly admits Tesla is significantly ahead and has the right approach.

However, because the tech was '50 years away', it never made sense for private sector investors, so most investment was from governments.

However, with solar and wind now far cheaper than nuclear due to no need for massive capital investments in concrete and steel upfront many years before production starts, does it even make sense for governments to go down this route?

The unreliability of solar and wind requires either hot (constantly running and spinning) non-renewable backups or grid-scale power storage (has never been done so ? on cost to build and upkeep) to guarantee reliable voltage and AC frequency. The cost of that should be factored into determine the true cost of these power sources.

The stability of the grid is dependent on the collective physical inertia of the many tens of thousands of huge and heavy spinning turbine-generator sets that make up the majority of the current generating capacity. Most current solar power sources rely on grid-following inverters, which are not stable without a grid stabilized by a preponderance of large spinning turbines. There has been some work on grid-forming inverters that are less impacted by this, but AFAIK there aren't currently any that can replicate the grid stability provided by that physical inertia.

I'm less certain about wind turbines, but I think they have this problem too. I don't think they're controllable enough to be mechanically synced to the grid frequency.

I'd love to be wrong about this, please prove me so if you can! But I don't often hear these points addressed, and we're not helping anything by ignoring the complexity of the real world.

As more and more intermittent renewables get pushed onto grids, they become more reliable. Most outages are from single points of failure from large generators or transmission. Dealing with highly distributed renewables means that grid ops get used to acting fast, and there's greater redundancy instead of so many SPOF. Kind of how cloud services got reliable by expecting there to be failure and designing it into the system.

Storage is advancing super quickly, is super fast to deploy, and can replace a lot of more expensive things like transmission upgrades.

We have all the tech to replace fossil fuels on the grid with the above. The only question is the final cost. It's likely to be far far lower than using existing "hard" energy, because by the time we can deploy 50 TWhs of storage, it will have gotten so cheap. We don't know when costs will stabilize, but they have a loooong distance to fall.

And we have all sorts of other technologies that will make all this far cheaper: enhanced geothermal, enhanced geothermal with temporal storage based on injection pressure and release, iron air batteries, flow batteries, thermal storage for industrial process heat, etc. etc. etc.

For every area of the energy economy, there are two to three solutions that look promising. Fusion and fission look promising for none. That's not to say that they can't have some serious innovation and start dropping their costs, but nobody currently operating in the field has demonstrated a path. Yet.

Batteries are also much better than gas at frequency regulation, and even at the prices a decade ago, completely took over the market for frequency regulation in the PJM market in the US. But frequency regulation is very very tiny in terms of power needs, it only takes a very small number of grid batteries to completely solve that problem.

The amount of batteries waiting in the interconnection queue completely dwarfs gas. There will be no "firming" coming from new gas turbines, unless old-school corrupt utilities are able to sneak it by PUCs by creating some sort of crisis and tricking them.

At least among the American TSOs, there are zero I know of that plan to do this. Do you have a source for one that does?

Trillions have already been spent on gas. That infrastructure will need to earn its return through the 2040s at the very least, and that precludes running them exclusively for firming. To the extent retrofits are being discussed, it’s as an add-on amidst full peaked functionality.

> Batteries are also much better than gas at frequency regulation

Limiting solar and wind by utility-scale battery capacity means scaling back EV adoption or solar and wind deployment. The math simply doesn’t work. (Again, in America. Without significantly raising rates. Not sure elsewhere.)

> it only takes a very small number of grid batteries to completely solve that problem

Frequency regulation is one component of firming. Batteries are good at some components, marginal at others. (As a system. Technologically, they're fine.)

Apart from de-industrialised grids, a batteries-only approach has been practically abandoned through the 2030s. It's why we're building so many turbines and abandoning nukes.

And also only Powerwalls produced in this quantity would have way lower prices. My point was batteries are getting cheaper every day.

Also the technology required has been around for decades it’s not new and no one’s done it yet.

So again what’s changed because it seems like for now there is no “I have a grid and need something now” solution it’s a “maybe one day”

But the real innovation is communication networks and IC control of the inverter. It's completely possible to create a waveform that modulates and responds to variation in frequency in the same way a large spinning mass would. And if reactive power is for some reason not enough, synchronous condensers are very old technology to solve that.

The problem isnt solar, or wind, or storage ... the problem is the grid. Were running on a system that was never designed to do what were asking of it, and yes its going to be a number of problems to solve. All of those are jobs, economic action and improvements to reliability and quality across the board.

> I don't think they're controllable enough to be mechanically synced to the grid frequency.

Google, there are a number of ways this gets addressed.

> There has been some work on grid-forming inverters

Yes, we know how, and the race to build them is on... this isnt a hard problem it's just a problem.

> grid-scale power storage (has never been done so ?

Already deployed in a few places with battery systems (hati, Australia both have them. Possibly Hawaii too). We're doing quite a bit of this. Again a quick google will give you a sea of sources.

There are now inverters that simulate the rotational inertia. They simlpy shift the phase of the generated waveform just a bit if the frequency starts dropping.

And it doesn't require any expensive additional hardware.

As a though experiment - imagine a 19th century world suddenly getting all of our current digital tech and wind farms and solar power - there would be no point in trying to create a "static" grid where producers and consumers weren't communicating with each other. Every consumer would negotiate power availabity based on momentary price.

An operator in Australia has seen massive success and profits over the past few years using batteries to out-compete other grid stabilization. IIRC, they have already made enough to pay off the upfront costs. Even better, Australian government was super against the change, but now most places are positive on them because of the obvious success.

I am however optimistic about grid-scale storage. There is a long term trend of rapidly dropping battery prices, and with recent developments in sodium ion batteries there is no fundamental reason this won´t continue. Another enabler could be advancements in lifespan. This could allow storage being installed inside or near wind and PV, cutting down on space and installation costs. Even then however, grid improvements would be needed.

Some problems still need to be solved indeed, but in my (mostly uneducated) opinion, they seem easier than achieving economically viable fusion. But they do still require large investments in R&D and manufacturing capability.

Wind turbines are designed to run on unstable wind speed -- this meant it have to somehow decouple from the main grid

They do not spin at 50/60hz, they are deployed with frequency converters to match optimum generation to the grid and spin at whatever speed they can achieve.

They're essentially another type of solar plant.

This is out of date. Grid scale battery storage has recently become economic in lots of cases and is ramping up quickly.

Being economic and being cheapest are worlds apart.

Solar or wind + utility-scale storage come in at 46 to 102 and 42 to 114 $/MWh, respectively, in terms of LCOE [1]. That does not include grid firming costs [2], which could raise the upper end of those figures to $120 or more, and is based on current storage prices; if everyone tries to build at once, it rises. (On the other hand, there are further economies of scale to be realised.)

Fission clocks in around 141 to 221 $/MWh, which is why we aren’t building it, but $31 at the margin, which is why closing working plants is stupid. SMR focus on lowering capital costs through economies of scale. Fusion by reducing compliance costs. In all likelihood, the solution is fusion SMRs baseloading solar, wind and geothermal energy with peaker industrial processes running during the day. (Hydro can come too.)

[1] https://www.lazard.com/media/2ozoovyg/lazards-lcoeplus-april... slide 2

[2] https://www.gevernova.com/gas-power/applications/grid-firmin...

This all definitely sounds like a great way to meet all our energy needs without carbon emissions ... in like 30 years? maybe 20?

We haven't invented "fusion SMRs" yet, let alone commercialized and scaled them. We're still in the extremely early stages of commercializing geothermal at scale. I'm curious what "peaker industrial processes" you're thinking of that can be profitable while running only during high power supply periods?

I think if we build a bunch of batteries, and then they turn out to no longer be useful after all this other stuff scales up, that's totally fine, far worse things have happened!

For instance, I just the other day came across an article about how in the first wave of electrifying the textile industry, they replaced big centralized steam engines with big centralized motors. But then they realized that motors made it possible to mass produce small machines and put one at each station, and they turned out to be an advantage.

I think there are a number of specific reasons to be skeptical of SMRs, but I don't think the entire concept is per se flawed.

A grid scale lithium ion battery, even completely burned up and vaporized into the atmosphere, is not dangerous in a comparable way.

For past 50 years, we had ["fusion never" level of funding](https://imgur.com/u-s-historical-fusion-budget-vs-1976-erda-...). Because of climate change, there is a sleuth of nuclear startups.

I wouldn't hold my breath for any of the startups. None of them (at least non-state backed ones) seem to have realistic way to the goal.

I remember reading a post from one of startups after rejection from NRC. It read like a blog post after being dumped by a girlfriend written at 3 AM, drunk.

On the other hand, it's not like nuclear is going away, e.g. Uganda and Kenya are planning on nuclear reactors. Maybe we should have a better option to offer than the light water reactors.

I encourage anyone curious to look up videos on SPARC on YouTube. It’s very encouraging! It seems honestly very reasonable that they will see sustained net energy gain for their entire power plant before 2030 (tho SPARC is still a demonstrator not designed for continuous service, so “sustained” means like one minute).

Here’s some videos:

8 years ago:

https://youtu.be/KkpqA8yG9T4

2 years ago:

https://youtu.be/KkpqA8yG9T4

Latest update posted yesterday:

https://youtu.be/w3Giq6NuPYs

That's a good plan, but ultimately, it's going to be a state backed (that's why I have "non-state backed ones" qualifier). CF is going to have a reactor with fusion with Q>1, but commercial product?

China is working on MSR. It has employs something like 700 Phds and 700 support personel for over a decade and has only recently made a research reactor. That's what I consider a serious effort (and that's for far simpler technology).

In my opinion, people underestimate how brutally hard it is to make new technology to work reliably. E.g. Superphenix, sodium cooled reactor had a capacity factor of 7.9% over a decade of production. That was after they had a demo reactor Phoenix with capacity factor 65%.

If we would like to stop polluting the air, the future of maritime shipping is nuclear (fusion or fission). China understands that, and invests in R&D necessary to make it happen.

Plus, on ships, there's no competition with solar or wind. And nuclear will actually be quite cheaper than bunker oil, if executed correctly.

Cargo generally isnt a target in the same way

Even putting aside exceptional situations like with the Houthis, we tend to get one or two highly public ship accidents per year. It would not be nice to have an incident like that involving a nuke ship every few years.

I feel like the solution for decarbonizing shipping would be carbon capture. Have the ships store the combustion products rather than exhaust them out, then reprocess them back into fuel on land using some other energy source (say, nuclear).

Now ask yourself this: do I want vessels flagged in the countries with the least regulations and the most corruption to be run by a for profit maritime shipping company that skimps on maintenance budgets and crew costs to be running nuclear reactors with highly enriched uranium (weapons grade) anywhere they want around the world, even through pirate territory?

Fuck No I don’t. I barely trust the nukes running them in the USN!

Biofuels is also severely limited in supply and will in the future most likely be reserved for aviation, which is a lot more constrained than shipping etc. when it comes to which fuel options can be retrofitted on existing systems.

Realistic fuels that are being used now: 1. Methanol. 2. Liquid methane.

If you have spare electricity (from any source), it's easy. Just capture some CO2 and react it with hydrogen with specific catalysts and at a high pressure. You can get methanol directly this way.

It's more expensive than fossil fuels at the current prices, so nobody cares.

Methanol is slightly preferred because methane can leak, and it's a more potent greenhouse gas than CO2. However, even most of the CH4 leaks happen near the drilling wells, and in pipelines. It's unlikely that synthetic CH4 will have to be transported over long distances.

Ammonia fueling infrastructure does not exist, and its failure scenarios are just not going to be acceptable. Meanwhile, LNG fueling infrastructure is rapidly getting built out.

What's worse, ammonia is also produced from natural gas, it's used for process heat and as a hydrogen source. There's pretty much no "green ammonia". So instead of round-tripping through ammonia production, it's easier to just burn the LNG directly.

In future, we can switch to green ammonia, but then we also can use power-to-gas or power-to-methanol instead. Both are more efficient than ammonia synthesis.

Methanol production, in particular, can potentially scale down to very small facilities. In theory, large utility-scale solar or wind farms can have a methanol synthesizer unit, that will produce it when there's more electricity when needed. It can then be transported by regular tanker trucks.

Proliferation will always be a risk with nuclear reactors. We will never have nuclear powered civilian ships, as long as there exist pirates out there. Sure, Russia operates nuclear powered ice-breakers, but there are no pirates in the Arctic Ocean, plus, for Russia the distinction between civilian and military is not all that clear.

As for hydrogen, I think ships are the killer app. High pressure tanks or cryogenic tanks benefit from the square-cube law. If you want them to be economical, they need to be really large. They will never make sense for cars, or even trucks, but they can make sense for trains, and certainly for ships.

Wasn't one of the promises of thorium reactors a much lower risk of non-proliferation? (Here's a fun question, can one make a pebble bed reactor design with pebbles designed such that if a ship sank, could a special magnetic sphere of a 'correct' size pull in the pebbles but keep a safe distance? IDK but trying to think outside the box here...)

I think it's worth remembering that for the sake of many ships, we do not need the power-density of an SXX or even an AXX per-se.

> As for hydrogen, I think ships are the killer app. High pressure tanks or cryogenic tanks benefit from the square-cube law. If you want them to be economical, they need to be really large. They will never make sense for cars, or even trucks, but they can make sense for trains, and certainly for ships.

The bigger the tank, the more rigorous the inspection has to be to avoid risks due to hydrogen embrittlement.

I'll admit, I'm -less- worried about that property on a train than a ship, but on a ship I think we'd first need to see good evidence we can maintain things of such size on ground safely.

We might actually get more "nuclear powered" civilian ships, in a way. The reactors will be on land, where they can be properly guarded. And the heat and power will be used to manufacture carbon-neutral liquid fuel.

We gotta remember what a lot of the Marine world really looks like, under the covers.

That is, lots of them will use HFO aka Residual Fuel oil or 'bunker fuel'.

Switching to Biodiesel? Probably the 'cheapest' of the options, not sure what if any implications exist from the switch (lots of ships will stop burning HFO in ports and switch to more common diesel/etc, however not sure if there is a difference in some engines with doing so long term)

Hydrogen Fuel cells are likely as much of a 'refit' from a labor standpoint as switching over to a nuclear reactor; Also the general issues of hydrogen embrittelment and the like have not yet been solved AFAIK especially for the volumes needed for large ships, also not sure if there have been a lot of studies as to whether the hydrogen embrittlement problem could lead to larger structural integrity issues on such a vessel.

Nuclear, OTOH, has had at least a few 'non-military' ships (mostly nuclear icebreakers) with good success.

The current 'whitewashing' strategy of cruise lines is LNG, for whatever -that- is worth...

Edit: finger slipped and hit post too early, so a bit was added, apologies!

Some shipping companies are experimenting with other ways to use wind. You can deploy kites to pull the ship, but that brings some operational challenges. The more promising idea are probably flettner rotors [1]. Those look like big spinning columns and work on the Magnus effect (how wind puts a 90 degree force on spinning objects). Their limited footprint makes them easy to integrate into existing designs, and since all they do is spin they are easy to use with the small crews of todays ships.

All of those modern ideas are mostly for reducing fuel consumption though, not replacing the engine entirely.

1: https://en.wikipedia.org/wiki/Rotor_ship

Huge kilometer square kites would be pretty cheap compared to the fuel budget of a ship, and clever routing and control systems can probably mean they reduce fuel consumption 80% for the same travel speed.

Not KM but 822m seems pretty close. I think you’re grossly overestimating the benefit from the kite. Seating’s current website says:

> A 1000m² sail surface to harness the power of the wind and tow ships. Based on modelling and preliminary land-based tests, Airseas estimates that the Seawing system can reduce fuel consumption and greenhouse gas emissions by an average of 20%.

I don’t think better routing will increase that to 80% even if you combine it with next gen tech that knows wave patterns and when a slot will be available to minimize speed and energy loss.

We need a path to remove fossil fuels from ships (& planes). There’s also industrial applications that need high heat that solar can’t really accomplish. Finally, solar & wind need insane battery capacity which when included pushes the economics strongly back in favor of fission and fusion.

We won't see discussions on that until we're serious about cutting fossil fuels.

It certainly does. The higher the pressure, the worse it gets. And it absolutely applies to storage.

There are companies that sell various technologies for hydrogen-resistant coatings for pipes, for example.

A fusion reactor is an extremely intense source of neutrons. The neutrons can be used to transmute elements, e.g. to transmute cheap natural uranium or depleted uranium into plutonium 239, which can be separated easily (in comparison with enriching uranium) and it can be used to make nuclear bombs.

Besides producing plutonium for nuclear bombs, it is also easy to use a fusion reactor to produce any kind of dangerous radioactive isotopes that could be used in terrorist activities.

So no, a fusion reactor that uses the fusion reactions that are possible today will not be any safer than a fission reactor, from the point of view of the proliferation risks.

If this works without the sun shining then, yes, it makes sense. It is always good to have multiple sources of energy even if only as a form of redundancy. Our world depends on power.

HVDC lines are already mature enough that the cheapest route is to just wrap the Earth with them to form a planetary grid.

The sun always shines somewhere.

Perhaps you're just talking about the Eurasian continent? What do the people of Western Europe do? Connect to the US?

Even then, we've seen with the recent Russia-Ukraine war that control of energy is a useful geopolitical tool with Europe being softer on Russia because of their reliance on their gas.

... and nuclear fuel and fuel rods from Russia. Which are still not being sanctioned btw. It's peanuts compared to the natural gas, admittedly, on the order of 700 million Euro per year.

A 2.5GW undersea HVDC line costs $2.5mln/km.

The cheapest nuclear power plant in Europe is the Ostrovets power plant in Belarus, the cost of which was $11bln for a 2.4GW plant.

For that money you could buy a 2.5GW HVDC line spanning the entire EU.

I think if we develop the technology we will find a use for it and be grateful that we have it, even if it’s hard to predict today what those uses will be.

While plasma confinement is currently done via supercooling of electromagnets(from last time I was looking into fusion) that's the major resource sink that I can see. We have massive fusion chambers, but I know some universities have built much smaller scale chambers. And we also can address the helium shortage if we solve fusion.

I'm not sure if fusion will ever get solved or if we will she commercial adoption. I also don't know what the life cycle of a fusion plant would be but its got to be cheaper than the big turbine blades, and more ecofriendly the photovoltaic cells.

They are not cheaper. They produce very low-quality electricity. If you want them to provide any supply guarantees, their price skyrockets.

1kWh of solar delivered midday, when there is 20% penetration? easy peasy.

1kWh of solar delivered at 2AM, when there is 65% penetration? much much more difficult.

These types of price comparisons are always unfair, always apples and oranges, because they always compare a 2AM kWh of nuclear with a midday kWh of solar, and of course solar wins that comparison.

2) it isn't. Modern reactors are designed to do load following. The French do that nationwide on a daily basis.

You also have hydro but it's a fairly limited (there are only so many valleys you can flood and so much water you can capture - plus historically it's the source of energy that killed the most people).

But if you truly decarbonise, and in absence of an economical way to store vast amounts of energy for a long time (wind can be down to pretty much zero for weeks on a typical year), and I don't see any such facility being built at scale, I am not sure what else than nuclear you can use to compensate for the volatility of wind. And because nuclear costs the same whether you use it or not, you then might as well save yourself the construction of a wind farm.

That's why I don't understand why we are spending billions building those gigantic wind farms. They only make sense if the intention is to keep using carbon. Otherwise they should spend that money on nuclear.

Cheaper per watts generated, which aren't constant. Cheaper for a constant output? Reliable to actually power a full grid through downturns such as storms, winters, etc? No, not really. There are exactly zero currently available widely usable grid scale (being able to have enough capacity to power the grid for up to days at a time) solutions. Pumped up hydro is the only one coming close, but it's expensive and it requires specific geography. Just saying "batteries" or "supply and demand by load shedding" doesn't magically solve this problem.

I don't know how much steel we need per square meter of PV (e.g. frames can be made from wood), but I do know the area we need for the current global electrical demand of 2 TW even after accounting for capacity factor and not just cell efficiency, and that our current production in each year is sufficient to put a contiguous 2 mm layer behind all of it:

http://www.wolframalpha.com/input/?i=%281.9e9%20tons%20%2F%2...

Given the panels are supposed to last 25 years, even at steady-state replacement rates, and assuming zero growth in the steel sector, and assuming none of that steel gets recycled when the cells themselves need refurbishment or replacement, that doesn't seem to be a real problem to me.

https://en.m.wikipedia.org/wiki/Earth%27s_crust

However this chart shows that iron represents more than 94% of all metals mined. That is, iron (used to make steel) is the most commonly mined metal by far. So actually more common materials can’t be used as no more common metal exists.

Also, very dumb question but the plasma means that fusion is actually occuring, right?

And does anyone know how this one collects the heat and converts it into electricity or whatever?

Or any other fusion device, how does it actually collect or output energy from the fusion. And how much do they make, and how far off is that from matching the input power?

Maybe it was some protons escaping from the plasma and hearing something external or something.

2. I don't think plasma == fusion. You can get plasma just by heating a gas beyond a certain point. Plasma cutters, for instance, operate on super heated air, no fusion anywhere nearby.

3. I think the wall of the reaction chamber heats up because they're being bombarded by radiation.

Most of the radiation incident on the reaction chamber walls is infrared, radiated from the hot plasma, but there are also more exotic things like stray neutrons also crash into the sides of the thing. These cause the metal to deteriorate over time (and become somewhat hazardous), but they also they impart additional heat energy.

So you have to have two cooling systems, one to keep the magnets actually cold so they they remain superconducting, and another to keep the housing below the point where it melts. It's this second one that let's you pull heat away from the hot metal donut that is a tokomak and use it to make electricity.

Between the magnet coolant and the chamber coolant and the reacting plasma you have some of the steepest thermal gradients anywhere in the known universe.

I would hazard to guess that no - they did not achieve fusion. They achieved plasma which is a precursor to fusion. Controlled plasma, at a high enough temperature, is an environment in which fusion can occur. All this article says is they created controlled plasma. Crucially, they did so with high temperature magnets which is fairly novel.

https://en.wikipedia.org/wiki/Fusion_energy_gain_factor You might also be interested in reading this. Q factor is what's used to discuss whether a fusion device is generating net positive energy.

> plasma is never "caused by" fusion

Which do you suppose comes first in a gravitational confinement scenario, plasma or fusion? It sorta seems like a chicken/egg scenario. I mean you gotta get those electrons out of the way, but where does he heat come from to do that, if not fusion?

https://en.wikipedia.org/wiki/Star_formation

No, since creating and maintaining the magnetic field in principle consumes no energy. All the energy put into a superconducting magnet (1/2 L I^2) can be recovered.

What is needed from a physics point of view is for fusion energy production to comfortably exceed the energy put into the plasma. And there's also a whole host of engineering and economic issues beyond that.

Energy is recovered from DT fusion by stopping the neutrons in a blanket, converting their energy to heat, and taking that heat away in a fluid.

As mentioned plasma is just another state of matter[1], where a significant portion of the electrons and ions a separate rather than combined as atoms.

Fusion happens when you overcome the electrostatic repulsion of nuclei, bringing them close enough together so they can fuse[2]. Typically, in reactors like this, that means you confine (compress) a sufficient amount of material ("fuel") to a small volume and heat it up sufficiently. Both are needed to make it possible for the nuclei to come close enough to fuse. The heat required is so great the material will turn into a plasma.

> And does anyone know how this one collects the heat and converts it into electricity or whatever?

This depends somewhat on reactor design, including fuel used. However they're all fancy steam generators in the end, so not unlike a traditional nuclear power plant in that regard.

From what I know, typically the "surplus heat" of a fusion reactor comes in the form of energetic neutron radiation[3]. This radiation is ionizing and as such shielding is required, and this shielding will heat up as it slows down those energetic neutrons.

In the ARC reactor[4] for example, a liquid shielding "blanket" surrounds the fusion chamber. As the neutrons heats up the liquid, the liquid gets pumped through a heat exchanger to produce steam to run a steam turbine.

edit: I found this talk[5] from one of the folks behind ARC to be very illuminating in how fusion power works and the challenges involved. It's from 2017, but the basics haven't changed.

[1]: https://en.wikipedia.org/wiki/Plasma_(physics)

[2]: https://en.wikipedia.org/wiki/Nuclear_fusion#Requirements

[3]: https://en.wikipedia.org/wiki/Neutron_radiation

[4]: https://en.wikipedia.org/wiki/ARC_fusion_reactor

[5]: https://www.youtube.com/watch?v=L0KuAx1COEk

No. Plasma simply means a specific state of a matter. E.g. the fluorescent lamps (the long tubular lights that flicker on start) have a plasma inside when it produces light

Or maybe it can go in the outside. I guess it's like, you need a huge amount of electricity to make the magnetic field strong enough, right? So the question is, how do you collect enough heat without melting key components?

You would pump water through the reactor and use a heat exchanger to a secondary water loop which powers the turbine. Maybe you can do without the secondary loop altogether, not sure; this ITER document suggests only one loop, but it's super vague: https://www.iter.org/sci/MakingitWork

Another reason why fusion is always 50 years away. It’s really hard (outside of a nuclear bomb or star, anyway).

The difference between energy harvested and the energy necessary to maintain confinement is the difference in denominators of Qscientific and Qengineering. Q is power out / power in.

Qscientific is a figure of merit used to know close to a burning plasma a machine is (how many fusion reactions it can do vs. how many it would need to do to be a working reactor).

Qengineering is power put on the grid / parasitic power needed to keep the machine running. Every electrical power source has an analogous concept (keep the lights on, fuel pumped, inverters operating, etc.) There are some noisy non-experts who claim that focusing on Qplasma is deceitful, but it's akin to complaining that engineers are focusing on engine efficiency instead of car efficiency before the engineers have finished making the engine. At the end of the day the scale of parasitic loads scales much less than the power output of a reactor, so the reactor size chosen will be at the economic minimum between "bigger machine is more expensive to make" and "smaller machine produces less power / lower Qengineering / other difficult scaling law things like neutron bombardment on plasma facing components (maintenance schedule)".

https://x.com/JB_Fusion/status/1506964692627034118

Yes, to have a real measure of Q you need to be doing fusion. In many research cases not a lot of fusion is happening and the neutrons are not actively being measured. What is typically done is to measure plasma performance metrics with protium or deuterium then say what the Q would have been if they used deuterium-tritium based on known plasma-performance to Q conversions (Lawson criterion).

https://en.wikipedia.org/wiki/Lawson_criterion

https://x.com/swurzel/status/1534556521744457731

Heat collection is done via neutrons. In D-T fusion 80% of the energy is released as a 14.1 MeV (17% speed of light, like a bat out of hell). The remaining 20% of energy is an acceleration of a He4 nucleus (fused byproduct). This He4 nucleus is a charged particle, so it stays in magnetic confinement and imparts its energy on fuel via collisions, helping to self sustain the reaction. The neutron has no charge so it flys straight out of the machine. You can model this as a small ring on the innermost core of the donut shooting neutrons in all directions. So you wrap a neutron-absorbing blanket around the vacuum vessel to slow these neutrons down via collision and heat up coolant in the blanket. You run this coolant through a heat exchanger to make pressurized steam to spin a turbine to... you get the idea.

https://en.wikipedia.org/w/index.php?title=Deuterium%E2%80%9...

If it displaced all remaining coal and natural gas burning, temperatures would stabilize.

Also, this is kinda like SpaceX getting a Falcon 9 to orbit the first time but in fusion land.

This company's ultimate goal is commercial fusion power, which has never been done. SpaceX's goal is landing people on Mars, which has never been done. The milestones being discussed are just stepping stones.

Cheap, frequent flights on reüsable rockets would seem to be space’s commercial fusion power threshold. Colonising Mars is like fusion SMRs at a fraction of solar’s cost.

Wouldn't the Sputnik moment require actual energy generation? It doesn't sound like they're any closer than we are.

Yes. Commonwealth Fusion and MIT are building a superconducting fusion reactor at Devens, Massachusetts right now. It's called SPARC and the site has been under construction since 2021. The plan expects to achieve first plasma sometime in 2026.

IP theft is a thing and yet China can't make Nvidia GPUs and I can bet $10 it won't be able to in 2030. I don't see why the west could 'just' copy a Chinese energy-positive tokamak even if it had all the plans. (Yes I know this one isn't that.)

The wake up call is for the west to be able to do that at the very least.

Now they are finding that actually its going to take a decade to reproduce what the chip fabs in Taiwan have built even with their help.

There's a reason that the wise engineers who built our only working fusion reactor put it about 1 AU away from us. Much cheaper and easier to just catch the energy it sends us.

TBH I would judge the world if they just went ahead and 'stole' it vs RAND licensing...

At the same time, I can see it being one hell of a hypothetical 'carrot' for lots of things, and of the current major powers, China is the only one with enough overall (political+humanpower+etc) will (at this time, anyway) to possibly make Fusion happen sooner than ITER can.

Strategically speaking, it would 'make sense' for them to pursue... Would the European union force NL's hand, to make ASML sell machines for whatever comes after EUV, in exchange for Fusion tech? Or all sorts of other fun things for the right Q factor?

Things become murkier.

HH70: major radius: 0.75 m, magnetic field 0.6 T SPARK: major radius: 1.85 m, magnetic field 12.2 T

HH70 has the advantage of actually existing and working, but to my completely layman eyes, it doesn't seem that using high temperature superconducting magnets brought expected increase in parameters.

I wish them best of luck and China speed. It doesn't matter who develops the technology, in either case it's a win for humanity. 7 out of 8 billion people are not in the "west".

The thing it, inertial confinement seems to be a dead end and has been for quite a while. At least rest of the world has decided to fund magnetic confinement (plus few oddballs with z-pinch), so I assume it's more promising approach.