The Anhei tokamak is first in the world to generate 100M degrees Celsius | Hacker News Reader

The Anhei tokamak is first in the world to generate 100M degrees Celsius

phys.org

135 pointslelf171 comments

What they never mention in these breathless articles is that your multi-billion-dollar tokamak power-generation system will be bathing itself in high-energy neutron flux, essentially destroying itself over only a few years, leaving a multi-hundred-ton radioactive husk to be somehow disposed of, or at least kept the rain from eroding and leaching radioactive slag into the water table.

Probably they would need to be built underground to begin with, so they would already be buried when they have been used up.

The pB reactor designs that emit mostly charged particles do not suffer from this problem, much, but get overwhelmingly less investment. There is a reason: the main purpose of the tokamak is a jobs creation program for high-neutron-flux physicists, to maintain a population to draw upon for weapons work. There was, and is, no intention ever to actually use tokamaks as an electrical-energy source.

Many involved will not agree with this. It is easy to get caught up in the technical challenge and leave worrying about practicalities and true motivations to others.

Where can I read more about this?

Terms to search for:

1 Neutron Embrittlement

2 Helium Embrittlement

https://www.aps.org/units/fps/newsletters/201610/fusion.cfm

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

https://arxiv.org/abs/1311.5079

https://www.sciencedirect.com/science/article/pii/0022311594...

Might as well add proton embrittlement to that list. Bane of hydrogen economies everywhere.

https://en.m.wikipedia.org/wiki/Hydrogen_embrittlement

The world economy manufactures and uses 50 million tons of hydrogen a year, so I think that problem has been well-solved.

So as someone who follows fusion somewhat I'm embarrassed to admit I'd never heard of this. For reference, pB here means proton-Boron [1].

To expound on what the commenter here has said: neutrons are a big problem for hydrogen-fusion reactors for two reasons:

1. A high-energy neutron represents a loss of a lot of energy, reducing the overall efficiency of the process since that neutron is basically "lost". It obviously has no charge so can't be captured.

2. Additionally, high-energy free neutrons tend to destroy their containers. I don't know if this will make the reactor itself radioactive or not. The commenter seems to think so.

Hence the idea of aneutronic fusion, which is fusion that produces no neutrons or very few. This is part of the attraction of Helium-3 fusion [2].

The neutron problem seemed so fundamental (in that neutrons are required to trigger fusion reactions, which is why you use deuterium and tritium rather than protium (Hydrogen-1) but those neutrons are the very problem that (so far) has made this method impractical. I remain skeptical if this particular problem will ever be solved. Neutrons are fine for stars. Stars are big so that neutrons don't go that far and they're big enough that gravity solves the containment issue.

It's also worth noting that there's no such thing as "free" energy. There is energy where the fuel is free (solar, wind and even fusion) but that still doesn't mean the energy is free. The plant that produces it costs money and takes up space. It must be maintained and it has a shelf-life. Look at the total cost of the plant over its lifetime and divide that into the power it produces and there's your baseline energy cost. So a $50B plant that produces 5MW for 5 years for no fuel cost isn't much use to anyone.

[1] https://en.wikipedia.org/wiki/Aneutronic_fusion#Proton-boron

[2] https://en.wikipedia.org/wiki/Helium-3#Fusion_reactions

I think some proposals on the design include a barrier material around the reactor chamber that would capture the neutrons and thusly convert them to heat, which can be used to drive a turbine.

IIRC the aim was to find a material that would convert to a shortlived radioactive isotope instead of a long lived one, so you can simply remove the barrier and have it sit in a quiet place for a few years, then recycle it.

Of course. Such a blanket is absolutely needed in a DT reactor, to regenerate the tritium that the reactor needs to keep running. But the materials from which that blanket is made, and the first wall separating the blanket from the vacuum vessel, are among the things that would be degraded by neutron exposure.

The "blanket" (pumped molten salt is frequently cited, or more exotic material, many feet thick) is needed to turn fast neutrons into heat, thence to boil water to drive a turbine.

But the equipment to contain the plasma, many, many tons of expensive stuff, has to be inside the blanket, and is destroyed in short order by neutron flux.

The "envelope" that keeps your "blanket" from spilling out all over the floor, a monstrous apparatus of pipes, is also being irradiated, but there are materials for the pipes that can stand up to it for a while.

This envelope is made in hundred-ton sections bolted together so it can be drained periodically and sections replaced. The used ones are radioactive and need to be kept somewhere safe.

This is all hugely expensive, finicky work that is very dangerous to be around, so you need even bigger remote-operated machines to do it.

So what's your opinion of the NIF? Even worse than tokamaks? Or is it actually more realistic as a future energy source?

NIF didn't work. It failed to achieve ignition. The simulation codes were bad.

A project called LIFE, to use NIF results to design an actual fusion reactor, was quietly terminated not too long after NIF failed.

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

Even if NIF had achieved ignition, it would likely, IMO, never have led to workable reactors. The targets are simply too expensive, and there's likely no way to protect the final optics (which have to be in line of sight of the targets) from hundreds of millions of explosions.

https://wci.llnl.gov/facilities/nif I don't think NIF was ever about energy research, just a way for government to spin weapons research as having some energy benefit.

"There was, and is, no intention ever to actually use tokamaks as an electrical-energy source."

I thought that's what DEMO which is planned to come after ITER is for.

I have listened to quite a few people working on fusion (ITER, also the people working on Wendelstein-X) and none of them were as negative as you are. Where do all the things you saying come from?

DEMO can be postponed indefinitely.

Have you heard of any significant investment in maintaining structural integrity of the tokamak itself?

Fission reactors need to maintain the integrity of the coolant pipes and the physical supports for the fuel, all just passive structure. I.e., valves, pumps, etc. are behind shielding.

It's all just basic physics. And basic politics.

Are you saying that all the people working on this this stuff are either idiots or liars? My impression is that there are a ton of problems but they believe they can be solved.

The people working on tokamak are engaged in fascinating technical problems, and generally leave politics and practical engineering problems to others.

They spent many years getting their particle physics degrees, and have no real job prospects besides this, research accelerators, or direct weapons work. You kind of have to feel sorry for them.

There are beginnings of private investment in what might turn out to be practical (i.e. aneutronic) fusion power systems, but they do not seem to need very many physicists.

How do you know all that stuff?

Friend of mine used to work on it. I think, from one of the pub chats we often had, the average number of times each atom in the reactor wall was expected to be knocked out of place by neutron collisions was in the order of 100.

This is why I am down on fusion compared to most advocates. On the other hand, I’m also up compared to most pessimists because the everlasting delay looks like it’s caused by an asymptotic-to-zero funding graph.

I still have silly ideas about how to improve the efficiency of Farnsworth-type designs — one I’ve never had time to simulate was “can star mode be enhanced with a simple magnetic field, and does it happen in the first place because of the magnetic field created by current flowing between inner and outer grids?”. I had that idea 10 years ago, I hope someone here has more time to sim it than I do.

Another thing that's rarely mentioned is that the power density of tokamaks will be very bad.

ITER's power density is 0.05 MW/m^3 (gross fusion power divided by volume of the reactor machinery; plasma volume is smaller). The power density of the MIT's ARC reactor is somewhat better, at 0.5 MW/m^3.

But the power density of a PWR reactor vessel is 20 MW/m^3, a factor of 40x better than ARC and 400x better than ITER.

Given that fusion reactors are much more intricate and use much more sophisticated materials and systems than a PWR reactor vessel, and are also much larger, the fusion reactors cannot help but be much more expensive per unit of thermal power output than fission reactors.

BTW, the main reason p11B fusion gets less investment is that for a given magnetic field the peak fusion rate of a p11B plasma is three orders of magnitude worse than for DT.

Of course one would not burn pB in a tokamak. So, that number is not relevant, although it is always trotted out to justify not diverting money from tokamak.

Practical pB designs rely on colliding beams as in the LHC, or other plasma-dynamic schemes that engage the materials in their own confinement.

Colliding beam schemes for p-11B will not work, as was shown by Rider and Nevins decades ago. This didn't stop TAE from selling such a scheme to investors, even though they were told it didn't work.

MIT's ARC design solves neutron flux by making the inner core of the reactor easily replaceable. The superconducting coils are hinged, so once a year they can just open up the reactor and lift out the core, which is 3D-printed. The core is surrounded by molten FLiBe salt, which functions as coolant and tritium breeder. The new superconductors allow the reactor to be much smaller than ITER for the same power output.

MIT's project has been spun off into the startup Commonwealth Fusion Systems, which has investment from an Italian oil company and Breakthrough Energy Ventures. Neither party has an interest in physicist job creation or weapons work.

There are at several pB efforts and one D-D/D-He3 (Helion, which says only 6% of energy would be released as neutrons) but it's harder to get net power from aneutronic fusion and we don't understand the plasma physics as well for the designs they need, so it's more of a wildcard at the moment.

Thank you, this is informative.

I will say here that I have no knowledge that pB aneutronic fusion can be made to work, but whether it can has no bearing on whether tokamak generators will ever go on line.

MIT's ARC design has an estimated cost of $29/W(e), an order of magnitude higher than PV.

Each 170 MW(e) ARC reactor will use 40% of the world's annual production of beryllium.

The "easily replaceable" in your description is quite a stretch. The replacement will be much more demanding than the replacement of fuel elements in a fission reactor. In the latter, the radioactivity is almost entirely contained inside the fuel elements, and they are simply transfered, as fuel bundles, to a cooling pool.

But the 86 tonne reactor vessel in ARC will have been permeated with tritium, and the tungsten will have been loaded with activation products by the intense neutron bombardment. It will be much larger than the rather compact arrangement of fuel rods that makes up a PWR core (about 165 tonnes of fuel, including structural material, in a typical 1000 MW(e) power reactor, which has nearly six times the power output of the ARC design.) The reactor vessel will take more space to remove. And then it will have to be crushed. The workspace in which this happens will become inaccessible to people, as it will become contaminated with tritium and radioactive tungsten dust. The overall volume inside the reactor building where all this happens will be very large, making the building expensive.

> There is a reason: the main purpose of the tokamak is a jobs creation program for high-neutron-flux physicists, to maintain a population to draw upon for weapons work.

No, that is completely misleading. The reason is that pB fusion requires 10 times higher plasma temperatures which are a much bigger problem then some neutron irradiation.

Neutron irradiation problem can be managed by using materials that don't generate long-lived isotopes on neutron capture and occasionally replacing the embrittled materials. Which are orthogonal solutions to solutions required for the already-difficult plasma containment for D-T fusion.

Translating activation energy, via required relative particle collision speeds, to crazy plasma temperature is a favorite rhetorical device of tokamak promoters. Those who know what they are talking about know that their brethren at LHC routinely achieve collision "temperatures" approaching 10^17 K. (That would be 100 million-billion degrees, or 10+ billion times as "hot" as hoped for a tokamak, if it actually mattered.)

Another way to say "embrittled materials" is "the reactor". And "orthogonal" here means that completely solving plasma confinement would not help at all with the problem that turning it on destroys your power station in a few short months.

But none of this addresses the statement quoted at all.

"Sometimes called an 'artificial sun' for the sheer heat and power it produces" No, it's because the sun is also a fusion reactor.

Very dumb but honest question: How are we certain that stars are fusion reactors and not, say, the other ends of black holes?

I am not an astrophysicist (or a physicist even) but one piece of evidence that may be useful here:

Based on our understanding of the nuclear fusion reactions, starting from hydrogen, we expect to see, for a star of a given light / radiation spectrum (viz. Young stars, old, white dwarfs, super giants, etc ), emit spectra lines indicative of different elements such as H, He, O, C, etc. [1]. Young stars may not have all the "heavier elements", older stars do. Their relative abundance also changes with age.

Our models & predictions of stellar nuclear fusion (afaik) correspond very well with the specific emission spectra we detect for different star types. Which also corresponds very well to the size / lifetime of star, etc.

So, the data is very very consistent with nuclear fusion happening in stars.

Now, it may be possible that they are just the "other ends" of white holes. But if it were so, then the model becomes far mode complex, plus, where are all the black holes? While I do not know if the total number / mass of all extant blackholes is as much as the total stellar mass, I would suspect it's far far lesser. Probably wouldn't add up.

This is just the first explanation that came to my mind. I am certain there are others.

Again, this is a non-physicist's lay analysis. Take it FWIW. :)

[1] https://en.m.wikipedia.org/wiki/Astronomical_spectroscopy

You could also ask if fusion is just energy from other ends of black holes. My point is that scientists can’t be there so see it but they have a very high probability that this is what is powering it based on theories and calculations

There is good evidence on the internal structure of the Sun from helioseismology. The results confirm models of the Sun's structure and temperature to high precision.

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

Because of this data, it was concluded that astrophysical explanations for the Solar Neutrino Problem (which cast doubt on fusion as the Sun's energy source) were not workable, and eventually a particle physics explanation (neutrino oscillations and the MSW effect) was shown to be the solution. The neutrinos are direct evidence that fusion is the Sun's energy source.

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

I am always amazed by the (low) price of those projects, compared to the potential benefits

$890 million for potentially giving a new clean energy source seems incredibly low. I can't see a reason why we don't have at least 10 of those projects being concurrently funded in the US, Europe and China. This is a fraction of a percent of the annual budget of each region.

Whoever gets their hand on that first is going to have a massive economical - and probably military - advantage over the others.

For just 10% of its military budget USA could have 71 of these running.

(I know, I know, of course, US labor is more costly than the Chinese).

>Whoever gets their hand on that first is going to have a massive economical - and probably military - advantage over the others.

If you were China, would you rather fight the US military (not going to work), or fight the US grip on world power via oil? Wow, if China switches us all to batteries and fusion, the petro-dollar and Texas economy are done for. That's far more than any military threat could ever hope to achieve.

Ya, but if China invents fusion power, it's not like it's going to stay in China. Inventing fusion power will (probably) not be a strategic advantage to the country that invents it. The technology will disseminate rapidly to the other major powers. What will happen is the middle east will stop being such a hot geopolitical issue, and will be relegated to the status of other countries that are important only insofar as their humanitarian crises are a source of guilt for richer countries.

This project is part of ITER-- China's contribution to an international effort to make fusion power a reality.

The Texas economy is already done for in terms of oil extraction. Fracking won't be sustainable for more than a decade or two. The benefits of fusion power would actually cement US power through space exploration and colonization more than any other country.

> I am always amazed by the (low) price of those projects, compared to the potential benefits

What would be the potential benefit?

In an optimistic scenario you'd end up with a technology that will likely have very high capital costs for construction and also very high infrastructure costs for transmission lines, because you create a lot of energy in one location.

Even in that best case I don't see such a technology playing a huge role in a future energy system. You end up competing with Wind, Solar and Storage decades into the future (i.e. they'll be much cheaper than they already are today).

Of course there's also the much more likely case: It just won't work.

Given that there are much more pressing needs in energy research (how do we manage storage once we get to higher rates of renewables? how do we decarbonize sectors outside of electricity?) there isn't that much in favor of fusion imho.

I surmise that effective fusion power would completely alter the space race forever, even before we figure out propulsion from this energy source. The scientific benefits from a potential large scale space platform with that kind of energy input would have enormity beyond measure, I'm sure.

Even if we don't leave the planet, the amount of energy that can be produced from a fusion plant would still offer tremendous benefits. You could run massive technological infrastructure directly around such a power source.

While one could say that humans themselves have little use of such a thing, I argue that fusion power could usher in a new age of humanity, despite the cost.

That line of reasoning sounds backwards.

The benefits would be clean, limitless energy and why is it likely that it will have a high capital cost and why wouldn't that be dwarfed by the availability of clean, limitless energy?

Claiming that somehow storage for renewables is a much more useful goal sounds more like ideology than anything.

Take the money currently going into solar and wind and put it to use there instead.

Solar and wind will never provide anything even close to what is needed for the energy needs of future generations or for any kind of progress in ex space exploration.

The high capital cost of fusion follows from some fundamental aspects of fusion reactor engineering.

http://orcutt.net/weblog/wp-content/uploads/2015/08/The-Trou...

“Long touted as an inexhaustible energy source for the next century, fusion as it is now being developed will almost certainly be too expensive and unreliable for commercial use.”

"As it is now being developed"

Lidsky was advocating movement to advanced fuels. Unfortunately, his PhD student Todd Rider shot down most of those schemes (the ones using non-Maxwellian plasmas). After that, Lidsky transitioned to fission and spent the rest of his career working on that.

If fusion is to have a glimmer of hope, it's D-3He (which produces maybe 5% of the neutrons of DT). But 3He is very difficult to get. Mining the moon for it is probably impractical, because the concentration of 3He in the regolith is too low (and the moon could only power Earth for about 1000 years even if it could be mined).

The future is a long time. Most breakthrough technologies are based on often decades or even centuries of research.

Perhaps. On the other hand, there are many more technologies than there are market niches for them to fill, so most technologies will be losers.

I see nothing that tells me fusion won't be a loser. The attachment some people have to it is bizarre. It's like they were told when they were young and naive that fusion was going to be the future, and are unable to revise their programmed opinions in light of contrary evidence.

Well I can tell you for sure that wind and solar are loosers.

So unless you have a better idea I have a hard time understanding what your point is.

How can you tell that wind and solar are losers? Their market shares are expanding rapidly across the world. They seem to be winning in the marketplace, not losing.

They provide less than 1% of the worlds energy needs and even if you project up to 2040 they are still only going to be providing around 3% of the worlds energy needs. How is that winning?

So perhaps you are the one who's been too tied to one specific narrative that's not holding up to reality.

In the magical world in which your argument there would be correct, technologies jump from 0 to dominant market share in a single discontinuous leap.

But we do not live in that cartoon universe. Here in real world, market share increases nearly continuously. On the way from 0 to 100, it passes near all the intermediate points.

What distinguishes a losing technology is not that it ever had a low market share -- all winning technologies did at some point -- but that they stop growing, and start losing market share. That describes nuclear, not renewables.

The potential benefit is lots of electricity, which may be abundant that when amortized over the "high capital costs" could be much more cost effective than wind, solar, and storage, or may not be. We have to invest in these relatively small projects to figure that out.

Furthermore, the highly geographically concentrated energy production from fusion power could work really well for energy consumers with a similarly localized nature. I'm thinking large scale carbon capture, energy intensive materials manufacturing or processing, or large scale ocean water desalination.

No, actually fusion is likely to be even more expensive than fission, and fission already cannot compete with wind and solar. Fusion takes the biggest problem of fission, high capital cost, and makes it worse, while reducing fuel costs, which are only a minor part of the cost of fission. It's bass-ackwards engineering.

Isn't the reason we don't have these cheap fusion projects because they don't produce usable fusion? Otherwise why would ITER have cost $20B?

Per the article..."Wu Songtao, a top Chinese engineer with ITER, conceded that China's technical capabilities on fusion still lag behind more developed countries, and that US and Japanese tokamaks have achieved more valuable overall results"

"I can't see a reason why we don't have at least 10 of those projects being concurrently funded in the US, Europe and China. "

I think it's the same reason why scaling up a dev team by 10x doesn't produce much more output in the same time. There are a lot of open questions in fusion that need to be worked out. Until one day someone will be able to put all partial solutions together into a working system. In the end it just takes time to try things, fail a few times and learn from others' failures.

There are several potential routes to fusion, the tokamak design is just one of them. We could pursue all options simultaneously.

Isn’t that’s what’s happening? ITER is a tokamak, Germany has built a stellarator. Other countries have smaller experiments. Right now nobody has a clear path to a commercial plant so they all try things and see which one works best in reality.

Tokamak research gets almost all the funding.

“Unlike fission, fusion emits no greenhouse gases”

Fission emits greenhouse gases?

They're probably taking the whole fuel lifecycle into account.

https://www.nirs.org/wp-content/uploads/climate/background/s...

Wouldnt then our “green renewables” also not be green due to their production lifecycle as well? Plastics, batteries, fiberglass, rare earth metals, cobalt, etc

To a small extent, yes. It's a matter of degree. Nuclear and renewables still have a much lower footprint than coal. It's just not zero.

We don't know the full lifecycle costs of fusion plants, but at least the fuel part won't involve open pit mining, unlike uranium ore, so it hopefully will be better than fission.

Nuclear have a much lower fooprint than renewables, requires much less space, last longer, is more robust, doesn't require rare earth materials or support from ex coal (like wind and solar often end up doing) as a base component.

Solar and wind is not even close to being in competition with nuclear when it comes to what is cleanest.

This LCA study shows wind, large hydro and 4Gen nuclear to be in the same range. With solar pv being higher.

https://www.mdpi.com/1996-1073/11/12/3452/htm

Still that is only greenhouse gasses and not full environmental impact. Renewables take up a lot of space.

Yes, but that space may well be someone's roof.

Not for anything substantial plus there are plenty of solar and (all wind) that doesn't sit on someone's roof.

Define substantial. Domestic PV installations reliably produce a significant percentage of domestic consumption - even in countries like Germany and the UK, which aren't known for bright sun.

Countries that do have bright sun typically skip straight to passive solar water heating systems, which can do an excellent job of eliminating water heating costs.

It's not like the world is running out of space anytime soon.

But maybe we don’t want to pave the Earth with PV panels...

The world is bathed in 100,000 TW of sunlight.

Current world primary energy consumption is 20 TW, 1/5000th of that amount.

In contrast, 11% of the Earth's land area is under cultivation for crops. Add pastureland and that increases to 37%.

Why the outrage over PV land use, when it will be just a pimple on agriculture's land use butt?

Well, taking PV array efficiency and land vs. sea area into account, that’s probably closer to 0.5% of Earth’s land area that would have to be covered with panels. Obviously not a huge amount relative to agricultural land but we’re still probably talking about a butt pimple around the size of California.

Primary energy use, though, is energy content of sources before they go through thermal cycles to get work. So one should also take into account the heat rejected in the latter. Nearly 80% of the energy content of gasoline, for example, goes out the tailpipe and radiator as heat.

PV would deliver energy in high quality form, electrical power, not as heat. So less than 20 TW, probably much less, would be needed to be equivalent to today's energy usage (although precisely how much would depend on details.)

Energy use will be increasing though, as the world gets wealthier. Still, this will also put pressure on agriculture to increase production, as demand for meat increases. Land constraints in the future will come from that, not from PV.

Because the energy density is extremely low compared to ex nuclear. And that it's not just about land use it's also about rare earth materials, the actual production of that many, the installation and maintanance plus no plans for decommision and it still needs ex coal to back it up because it's unrealiable.

Solar doesn't use rare earth elements, although that's a favorite fake talking point of the anti-renewable astroturfers.

What do you call indium, dysprosium, praseodymium, neodymium and terbium, if not rare earth metals?

I call them things that are not used in silicon solar panels.

Also, indium is not a rare earth element.

So this is wrong?:

https://motherboard.vice.com/en_us/article/a3mavb/we-dont-mi...

Yes, it is wrong. Rare earth elements are not used in solar panels.

Understand, there's been this obnoxious effort by anti-renewable propagandists to spread the lie that PV is dirty because of rare earths. Shellenberger was spreading this falsehood. But it has no basis in reality.

vice is pro renewables, so that make no sense. Can you provide som evidence that rare earth metals are not needed?

Vice is just mistaken, not lying. I will charitably assume the same is true of you.

Are you REALLY asking me to prove a negative? Tell me, what purpose do you imagine rare earths serve in silicon PV cells? They are not used as dopants (that's boron and phosphorus). There are no magnets. The glass doesn't require them, nor do the structural metals.

So they cut down the rainforest for fun? Didn't know that.

Is this supposed to be some kind of joke? I can think of many reasons why the rainforest is cut down but lack of space for PV isn't one of them. Just think about it. Cutting down trees costs a lot of money in terms of acres. You need expensive machinery, trained workers and a lot of time. In other words people who cut down the rainforest do it with the intention to make a profit selling the wood they cut down. People who "care" about the land itself first burn down the trees because it is faster/cheaper and second because the ash acts as fertilizer in the short term. The rain forest is also rich in a fertile soil called humus which again acts as a fertilizer. But this layer of humus is quickly depleted because it is no longer protected by trees and simply gets washed away. The end result is infertile land and the farmers have to burn down the rainforest again. It's not like this is unexpected. The similar things happen on regular farms which is why we use artificial fertilizer, so in other words: people destroy the rainforest because they want to make a quick buck. If they really cared about the land they wouldn't abandon it as soon as it becomes unprofitable.

I don't think it makes sense to assume that there is an energy technology that doesn't produce environmental harm. Nuclear power plants increase the temperature of rivers and they are pretty good fish killing machines.

Doesent take entire chain into account. Also keep in mind wind and solar needs backup powers thats often coal. Nuclear is by far the grenest.

Coal is terrible in terms of load following. What are you even talking about? If anything, coal plants are economically unsustainable. They don't respond to short term changes in electricity prices and therefore still produce electricity even when they are losing money.

Yet they are used as a backup for both wind and solar because those are unreliable energy sources. That's what I am talking about.

Coal isn't economically unsustainable I don't know where you have that from.

Wind and solar covers less than 1% of the worlds energy needs even push forward to 2040 and it might do around 3%.

It's not even close to being a serious contender for humans energy needs.

> wind and solar because those are unreliable energy sources

They are unreliable but not unpredictable. Weather forecast provides adequate production estimates 48 hours, and precise ones 12 hours into the future (especially when averaged over large areas). Enough time to fire up standby power generation.

Also while wind and solar are unreliable by themselves, they become a lot more reliable once you combine them. That is because when there is little wind, it is usually sunny, and when there is little sunshine it is usually windy. At night, when there is neither, the power consumption is low.

The major problem that needs to be addressed with substantial amounts of energy storage is overcast winter days with no wind, when power consumption is high.

> Coal isn't economically unsustainable I don't know where you have that from.

According to a 2018 report[1] of the German Environment Agency (UBA), the economic cost (health and environment) of coal power is an additional 0,19 €/kWh over the generation cost. This makes it unsustainable compared to other energy sources and only profitable because the public bears this cost.

> Wind and solar covers less than 1% of the worlds energy needs even push forward to 2040 and it might do around 3%.

Someone should tell the Chinese, because they are already at 5% from wind alone.

[1] https://www.umweltbundesamt.de/publikationen/coal-fired-powe...

Being predictable doesn't really matter. Denmark had a great summer in 2018, that meant the wind didn't blow which means they had to import energy from Germany. Germany has plenty of solar yet they ended up using coal to provide that energy. The weather was amazing in Germany too yet they didn't actually provide Denmark with solar energy.

I don't think you done any serious research into this to be quite honest.

Then there is capacity factor wich is a whole other problem (look it up)

To claim that coal isn't economically sustainable is absurd. It's more or less the cheapest we have.

With regards to China thats 5% electricity NOT energy. Again I don't believe you actually did any fundamental research here or you wouldn't throw out these numbers that does not support your position.

In a decarbonized economy, burning no fossil fuels, why should PV emit any CO2?

Nuclear, on the other hand, is going to still have lots of concrete, and making concrete emits CO2 even if the energy to calcine the limestone comes from non-fossil sources.

Yes, one could capture and sequester the CO2 from concrete manufacture. But then one could also capture and sequester putative CO2 from PV manufacture. So if sequestration is on the table, the CO2 argument being made against PV in favor of nuclear just collapses anyway.

There will not be a decarbonized economy running on wind an and solar. It's less than 1% of the worlds energy consumption and won't be more than 3% in 2040.

Nuclear doesn't us "lots of concrete" in any meaningful way especially not when you start factoring in the energy density.

Wind and solar require huge areas, lots of rare earth metals and there is no plan for how to decommission plus, wind and solar are unreliable which means they still need backup from something else like coal, nuclear or oil.

In other words there will be no decarbonized economy without nuclear or fusion or thorium.

I have no idea where your figures come from, but they appear to be wildly inaccurate.

https://www.iea.org/renewables2018/

No they are quite accurate. You are conflating electricity with energy. Energy is much more than just electricity.

Furthermore, when you hear countries like Denmark and Germany talk about x amount of percentage being wind or solar you need to remember a few very very important things.

1) They are talking about what that specific country produces, not what it consumes. 2) What it consumes includes what it imports. 3) Wind and solar only produce electricity which is only part of our energy consumption 4) You also have to factor in the capacity factor which for wind and solar is between 20-40% and nuclear is more or less 100%.

In other words, those high numbers only come from ignoring the entirety of energy needs. The renewable energy sector and its proponents are very disingenuous when they present their "success".

Your 3% prediction for wind/solar for 2040 seems dubious.

Here's BP projection:

https://www.instituteforenergyresearch.org/uncategorized/sna...

They have renewables (excluding hydro) supply about 15% of world primary energy demand (not just electric energy demand) in 2040 (although that also includes biomass, waste, and geothermal).

The other consideration is what the wind/solar displaces. 1 joule of wind or solar displaces several joules of primary fossil fuel energy, if the latter were being used for electric power generation. No one benefits from the fraction of fossil primary energy that gets dissipated as waste heat.

Where does this 3% projection come from?

I assume they meant to say it creates no radioactive byproducts.

Article seems to have been very poorly edited.

Most fission reactors that have been built so far use lots of concrete.

And there are utility scale mounting systems for PV that use no concrete at all, just steel earth anchors.

Looks like the article has been edited to fix this:

> Fusion emits no greenhouse gases. Unlike fission, fusion carries less risk of accidents or the theft of atomic material.

I like how they converted the number to Fahrenheit for the American readers - like that helps grasping this in any way. :) the comparison to the sun's core is much more helpful in this regard, but I still just cannot process how we're able to do this in a controlled fashion. If this technology really ever reaches production quality I'll be truly amazed.

But they did it wrong. The correct number is 180M degrees Fahrenheit. Sigh.

If 100C == 212F then 100 million C == 212 million F. DUH. Just like 0 C == 0 F. Simple math, man. High quality article all around here.

100M C to F => 100M*(9/5)+35 = 180,000,000 + 35 = 180,000,035.

...whoa

you mean 32?

Lol, yup. I just realized furgoo was being sarcastical (I hope)

Well, and they did it right, too. In the image caption,

> The Anhei tokamak is the first facility in the world to generate 100 million degrees Celsius (212 million Fahrenheit)

In article body,

> Most recently in November, it became the first facility in the world to generate 100 million degrees Celsius (180 million Fahrenheit)

> But sustaining the high temperatures and other unstable conditions necessary is both extremely difficult and prohibitively expensive—the total cost of ITER is estimated at 20 billion euros ($22.5 billion)

Sadly, this maybe 3-5% of the annual US defense budget? Shows where our priorities are that it's considered "prohibitively expensive".

Check to see if your House rep or either of your senators is on an appropriations committee. If so, tell them how you would like to see the appropriations for the Department of Energy, DoD, and other departments change in Fiscal Year 2020. (The FY 2020 bills could start getting passed in the next couple months.)

Are there examples of direct representation actually working this way? I try not to be too cynical, but I havent seen good examples of a Congress member’s constituency being able to significantly influence their behavior outside of their reelection campaign.

Bang a drum about China over taking the US and making it into a third world country. That's how Nasa got funded.

Yeah, it's pretty sad how even the international community combined can't come up with that money while they piss away multiples of that with weapons purchases and subsidies to already filthy rich companies and people

It is not only sad; it is a political call to arms.

If you want to stop the waste of blood and treasure, actively participate. Complaining is free, yet wildly ineffective.

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

Tax payers have paid billions for this over decades and while no doubt physics has benefited there's nothing to show for it in terms of a practical large scale application to generate energy from fusion. Why do you think merely throwing money at this project will do the trick after all this time? Politicians can of course use your argument to score over opponents in the realm where details don't count.

Not all funding is equal. For example compare investments in the Space Launch System vs. Falcon Heavy.

Investments in ITER are also fairly inefficient due to the political strings attached. Countries get concessions in exchange for funding, which makes it logistically far from optimal. It's also a slow-moving behemoth which makes it difficult to incorporate newer technologies as they appear, e.g. improved superconductors.

I think it would at least be a good idea to throw some more money at smaller projects that can iterate faster than ITER.

Also, past funding is not necessarily equal to current-day funding. Materials sciences and computing have advanced, so we can build on technologies that simply didn't exist back then. One example is simulation of plasma instabilities.

There has been a lot of progress. Lots of hurdles were overcome. If you put the chance of success st 5% if we invest another 50 billion, we should do it. In the long run, it will ensure our future.

If da Vinci had 50 billion, he still wouldn’t have achieved flight. There were things he just didn’t know, and until those things were learned, all of his efforts were in vain.

We’re still learning too.. and there’s no telling if we know enough to achieve fusion. It may require physics that we won’t learn for another 100 years. Until it’s invented, we don’t know what’s required.

I wouldn't bet against it, 50 billion in 1500 would be about 50% of the GDP of the largest economy of the time (China). It's Apollo program funding level.

http://www.newgeography.com/content/005050-500-years-gdp-a-t...

>It may require physics that we won’t learn for another 100 years

It may require physics that we won’t learn without another 50 billion

Apart from the initial cost construction and maintenance. Are there cost of Fusion in terms of cost/W? Or do we get Free, limitless Energy?

Wouldn't the first country achieve this be in huge / leap forward advantage? Especially for a country like China with lots of Production and Exports.

Running a fusion reactor will still cost significant money. It's a very complex machine.

And it can’t be built everywhere where energy is needed, due the its complexity.

I assume you mean cost/J or cost/MWh. Construction and maintenance will be most of that. Most credible fusion reactor designs product a lot of neutrons, and neutrons get absorbed by most materials and degrade them. (And turn some materials radioactive — avoiding long term radioactivity is an important design considerations.)

There will also be staffing costs, fuel costs (small, but still — deuterium and tritium aren’t free), and even costs associated with obtaining cooling water.

The big benefits of fusion over fission, as I see it, are that the fuels are safe and plentiful, the byproducts are harmless (if neutron activation is well managed), and the reactor itself isn’t full of extremely dangerous materials. If you turn a fusion reactor off, it’s off, and there’s no risk that it accidentally keeps reacting.

Does it also reduce proliferation concerns?

You can not make a bomb with fusion materials alone. Hydronuclear bombs use fission materials (uranium, plutonium) to start the fusion reaction.

However, maybe a fusion reactor may be used for fission bomb research, but I'm not sure how.

Looks like fuel costs are really low, but maintenance and replacement component cost might be pretty significant: https://www.sciencedirect.com/science/article/pii/S036054421...

It will have a renewables-like cost structure in that it will be really expensive to build, with a finite lifetime, and modest operational costs.

No doubt some time in the first few years there will be some unforseen new kinds of maintenance requirements and failure modes to discover.

It will be much more expensive than renewables, so saying it has a "renewable-like cost structure" is not accurate.

Given complexity and high material stresses, fusion reactors will also likely have very high operating costs. DT reactors, in particular, will require replacement of major structural elements every few years due to neutron damage.

If the gross fusion power output of ITER were converted to electricity at 40% efficiency, and you ignored the power needed to run the reactor, and also ignored the cost of the breeding blanket, turbines, and generators (which ITER doesn't have) then the capital cost would be about $100/W(e).

In contrast, the cost of installed utility scale PV is around $1/W.

Would a run away reaction turn earth into a sun?

Seems unlikely - once the magnetic bottle collapses the reaction stops, its very hard to keep it going. Its not like fission where the reaction cascades and causes a melt down. Some localised melting is perhaps possible if things go astray.

2050 :'(

That's 180M degrees Fahrenheit, for those of us who are American, Liberian, or Burmese.

"EAST's main reactor stands within a concrete structure, with pipes and cables spread outward like spokes that connect to a jumble of censors and other equipment encircling the core."

Even reactors are not exempt from censorship!

Maybe the energy it generates will power the censors?

I tried building a fusion reactor once, but now I see my main failure was only using one censor. She couldn't possibly catch all of my 'mistakes', so I just removed her, but that didn't help too much. It's clear now that when things aren't working properly, the answer isn't to eliminate censors, it's actually to add an increasing number until things start snapping into place. Next time I'll use a jumble.

Entertaining typo/correction for "censer", I suppose?

sensor probably?

I would assume no incense burning (censer) in there.

Yay English!

A censer censor sensor is something that detects someone who covers up the existence of incense burning things.

Not to be confused with a censer sensor censor, who censors the censer sensor's central censer detections.

Two comments ago, I knew what all those words mean. Now I'm not sure...

Sensor, probably :)

This may be how China wins. While the West has capitulated to the hippies in moving to renewables and conservation, China is investing in increasing energy production capacity through nuclear. (Not just research into fusion, they’ve got 20 fission reactors under construction right now.) More energy means more economic capabilities and more war making capabilities.

If you read the article you'd realize they're still late compared to western nuclear technology. It's great that they invest a lot in the technology but that's both wrong and premature to award them any achievement.

Sure we’re ahead. But we’ve stopped trying, and diverted our resources to dead end technology.

Nuclear is dead end tech. Renewables are cheaper than nuclear without the PR problems or risks, and getting cheaper all the time. The future is solar, wind, and hydro with a lot of energy storage and long distance transmission.

Renewables will, at best, allow us to maintain our current energy expenditures in a more sustainable manner. (If that.) But they are incredibly space inefficient. Nuclear is the only avenue for increasing our energy production by an order of magnitude or more. (Not to mention, there is no such thing is a solar powered attack submarine or aircraft carrier.)

I call bullshit. 12 million acres of solar panels could power the whole of the US. We already lease twice that amount to oil and gas and twice that too just growing corn for ethanol. Solar would actually be a more efficient usage of land than the status quo just in terms of energy production.

The competition isn’t oil and gas, it’s fission and fusion.

Fission and fusion have already lost. As Amory Lovins has pointed out, just the non-nuclear part of a fusion power plant would make it too expensive to compete. The reactor itself would have to cost negative dollars for the whole power plant to be competitive, and that's unlikely.

https://www.forbes.com/sites/amorylovins/2014/09/07/fusion-p...

While this seems an unpopular opinion here, it's correct. The economics are such that fission is out of the game, and fusion is out before it even got a chance. Now maybe one day we're using so much land area for solar and wind that it changes the calculus. But at least for this century renewables are going to dominate.

Why should we want to increase our energy production by an order of magnitude?

Maybe a new generation needs to read E. F. Schumacher.

Building a fully electric transportation network, supporting a greater population, advanced weapons like rail guns, etc. You know, progress. The future. Maintaining our technological supremacy.

China, Russia, etc., aren’t going to be reading E.F. Schumacher. Energy production equals economic, military, and political power. Whoever figures out how to break past the fossil fuel bottleneck is going to own the future.

And for space exploration. Nuclear propulsion would enable humans to reach Alpha Centauri within a lifetime.

No, fusion could not allow humans to reach Alpha Centauri in a lifetime, unless you mean they flew through the Alpha Centauri system without stopping.

If you want human interstellar travel, that probably means beamed power propulsion. That's a better solution anyway, since it allows higher power density at the vehicle. There is no need for fusion for that.

Let's restrict it to travel within the solar system. We'll need fusion to power all of those beams.

Why is fusion needed to power the beams? Sunlight would work just fine.

There is a cap on potential solar power generation. Compare the amount of power generated per square meter for a solar panel versus a nuclear power station. Nuclear reactors can be stacked vertically or located underground. Also it is ugly to have vast areas of the natural landscape covered in panels. Ugly waste of space.

We're talking here about solar collectors IN SPACE, where the beam sources would be placed. The cap there is the entire output of the Sun.

So we can take over the galaxy.

What exactly is dead end tech here? Dye sensitized solar?

If you read the article even closer, you'd see that it's part of an international collaboration that includes nearly all of the advanced industrial nations, including the US. The entire point of ITER is to be a stepping-stone to commercial fusion power in the next few decades. As always it is certainly interesting news when Chinese mega-experiments are on parity with the US or Europe, but so far big fusion reactors are like Top-500 supercomputers in that respect - dual use technologies whose economic value is marginal at best.

The Chinese government can afford it.

If you want nuclear here in the US, the government has to kick in the lion's share of the funds for it. That's just the situation we're in. Even with no regulation and taxes at all, nuclear is just enormously expensive compared to just continuing to use coal, or just slapping up some windmills someplace.

People have to be willing to take the tax hit, one way or the other, to get nuclear. Witness Vogtie. Where the government has come to the rescue and made a law forbidding residents from buying the cheaper wind or coal power. Literally. No one can switch from using Vogtie power. That's the sort of assistance that nuclear needs. (Yes, I know that Vogtie is late and still over budget despite the unprecedented government assistance. But that only reinforces my point really. Even Vogtie, which now has guaranteed captive customers, still needs semi trailers full of cash to make it work.)

> Even with no regulation and taxes at all, nuclear is just enormously expensive compared to just continuing to use coal

Given access to enriched uranium and no regulation, a nuclear reactor is basically a high school science fair project.

In practice you're going to want a larger scale than that and a design from a team of professional engineers rather than a high school student, but it should still cost an order of magnitude less than it currently does, with the difference attributable primarily to regulatory compliance costs.

Some of those regulations are obviously important, but many of them are purposely designed to increase costs, lobbied for by competitors who want nuclear to be uneconomical.

Even a simple change like having the rules a plant is constructed under be the ones in effect when construction begins rather than when it ends would be a significant cost reduction, because as it is one of the major costs is that the rules for "new plants" often change after the relevant portion of the plant has already been constructed.

> People have to be willing to take the tax hit, one way or the other, to get nuclear.

Maybe we could just start by leveling the playing field. Renewables and fossil fuels are already directly and indirectly subsidized, either eliminate those or apply them equally to nuclear. We need to price carbon. Use the same standards for radioactive emissions for coal and nuclear. If you're going to require nuclear to pay up front for decommissioning and price in various other things then do the same for everything else etc.

These are excellent points. If everyone was forced to pay the true cost of their energy consumption, including not just fuel and up-front capital costs but long-term environmental remediation, accident insurance, and so on, how expensive would the various technologies be?

In complete fairness here, wind does have to pay "not just ... up-front capital costs but long-term environmental remediation, accident insurance, and so on". Farmers and the various states' departments of natural resources don't just hand over their land for free with no strings attached, and insurance on those windmills is not cheap.

Even so, it still comes in orders of magnitude cheaper than nuclear.

People keep saying nuclear is really expensive.

https://www.instituteforenergyresearch.org/renewable/electri...

https://www.energy.gov/sites/prod/files/2015/08/f25/LCOE.pdf

Moreover, "orders of magnitude cheaper" means hundreds of times cheaper. You would have to be doing something silly like comparing one 3MW wind turbine to one 3000MW nuclear reactor.

If you look at what nuclear power plants actually end up costing, they are very expensive. Paper studies that promise us otherwise don't make up for that. It's been the consistent history of nuclear power that those promises aren't worth the paper they're printed on.

Nuclear proponents: This should be cost effective.

Nuclear opponents: [Change laws/rules during construction to drive up costs on purpose; cost is now more than projected but still less than coal]

Nuclear opponents: Look at all these cost overruns. It now costs more than solar would if we solved the nighttime problem with hypothetical cheaper storage technology that doesn't currently exist, therefore nuclear is unviable and we should never attempt it again.

No, what actually happened was the nuclear vendors lowballed their bids, confident they could either reduce costs or get the customers to pony up more later. Regulation is just the excuse they gave when the inevitable happened.

That also happens, but that part happens with all construction projects from bridges to fiber rollouts -- including the construction of other types of power plants:

http://schlissel-technical.com/docs/reports_35.pdf

Utility scale PV typically comes in within 10% of estimates.

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