Can Nuclear Fusion Put the Brakes on Climate Change?
newyorker.com"Can _insert technology we don't have yet and that requires breakthrough_ save use"
Yeah sure, why not
Nuclear is already the answer but people are afraid and even countries lead by "smart people" such as Germany are slowly decommissioning their nuclear power plants...
In the meantime we're using more and more energy while putting all our eggs in the "intermittent energy sources" basket. It might have been fine if we all lived like 1960s era people but I don't see how that would work in today's world
Germany is slowly decommissioning their nuclear power plants because of Nord Stream 2. Gerhard schroeder almost immidietly becomes head of NS2 after he steps down as chancellor.
https://www.bbc.com/news/world-europe-27202794
There are no accidents when it comes to big things like that
For sure it's not an accident, they also have a big anti nuclear movement since the 70s.
I live in Berlin and I don't know any German who is for nuclear power
I live in Berlin and I don't know any German personally who is not for nuclear power.
I used to be so excited about fusion, but then I actually learned more about it. Perhaps I'm missing something, but the benefits over fission seem underwhelming.
It's about the same cost on a per-megawatt basis. Modern fission plants are totally safe. Nuclear waste is basically a non-problem, especially with the most recent technology.
And fission has the huge benefit of being a mature, proven technology.
What's the big benefit of fusion that makes it worth investing so much money?
The only thing I can see is that it doesn't require uranium, which can be abused to make weapons. But does that by itself justify the investment?
Don't you think that the fact that you can use sea water as input and you get hydrogen as output is a huge advantage over fission?
Add to that the fact that there is no fukushima style meltdown in a fusion power plant. If something goes wrong, it just stops.
Finally, contrary to fission, fusion power plants will be able to adjust their power output as fast as gaz power plants. It takes months to turn on or off a fission power plant.
So yes, there is definitely a few benefits to fusion. And take a step back on the numbers. Look at how much we injected in banks in 2008. If it works (and indeed there is a risk they won't make it work and this is probably where the argument should be) the investment would be amortize over thousands of years...
Can you imaging a guy, 3000 years ago in China, complaining about spending money on a kiln to smelt that thing called iron?...
> there is definitely a few benefits to fusion.
Absolutely. But these benefits are vastly outweighed by one benefit shared by fission, solar cells, and wind turbines: those things are real.
Thats the argument of coal plants for solar and at el sources of energy.
Not feasible, too expensive, doesnt work.
And yet here we are.
Fusion isn’t real yet - every technology you listed wasn’t real at some point relatively recently.
The problem with “not real yet” is that it applies equally to things that eventually became real, and to things that never came to pass. We once said the same about both fission power and flying cars, and yet I still drive on the ground to get my groceries.
There does seem to be some movement in fusion technology, but it has also been in the “soon” state for decades now. There is no obvious way to balance these two contending data points
The first fission reactor was in activity 10 000 years ago. Well, probably not even the first.
Wind power was exploited since the 11th century? Or is it 13th? I'm not that clear on that. Solar cell appeared somewhat late in the 19th century.
Fusion is real too, and older than all of those. The issue is the scale.
> The first fission reactor was in activity 10 000 years ago. Well, probably not even the first.
What are you referring to?
Maybe something like this: https://blogs.scientificamerican.com/guest-blog/natures-nucl...
and man will never go to the moon...
>> Add to that the fact that there is no fukushima style meltdown in a fusion power plant. If something goes wrong, it just stops.
Well, so does any gen3 fission reactor. That makes the gen 3.5 EPR "now with core-catcher" an over-engineered, useless and costly project.
>> Finally, contrary to fission, fusion power plants will be able to adjust their power output as fast as gaz power plants. It takes months to turn on or off a fission power plant.
No, it takes up to 6 hours on gen3, depending on design. Some French reactors can go from 100% to 0 in less than an hour, and from >0% to 100% in two (although this is very, very inefficient). A 5% change, in some cases, can be reached in 15s. The issue is that everytime a reactor is not running at 100%, you loose a lot since all the cost stay the same (fuel cost is less than marginal).
The main advantage of fusion is near-infinite available fuel at current energy consumption. That said, with Gen4 and all those new shiny research on surgenerating reactors, the same could be said of fission. I guess the main issue is our appreciation of risk.
> Look at how much we injected in banks in 2008.
If you're talking about the US, those were loans which, simply put, returned a profit to the US within a short number of years.
https://projects.propublica.org/bailout/
$634 billion out, $743 billion in for about $109 billion in profit for the taxpayers in about ten years.
While I agree that major investment into future technology is important, I think comparing it to short term loans that had collateral in the form of bank equity, and which were repaid with a profit to the government, is a poor comparison.
Fission already lets you generate zero-Carbon power from cheap fuel, at the cost of constructing a monumentally expensive plant.
Fusion sort of looks like it will give you that dynamic, only more extreme. Fuel even cheaper, plants even more expensive and time-consuming (and risky, given lack of track-record)
Solving the waste problem is nice, but not climate-relevant (and you will still be generating a bunch of activated metal due to all the fusion neutrons)
I agree with you that humanity wants to be fusing a lot of hydrogen in 100 years. I don't think it's super relevant to the challenges of the next 20, though
Prototypes and early models are extremely expensive but there are encouraging signs that fusion plants could be cheaper. The technology is inherently safer so site-preparation would be cheaper (can be a massive bill for fission), the same consideration could lead to factory-style production of magnets and other similar components, more interest from the public (safe, climate-friendly) and any sea-touching countries (energy-security) would mean more demand pushing economies of scale further, safer means less time passing certification, etc.
>Add to that the fact that there is no fukushima style meltdown in a fusion power plant. If something goes wrong, it just stops.
That's already the case with the CANDU reactors. They also don't need upgraded uranium, and can use uranium from decommissioned nuclear weapons.
> If something goes wrong, it just stops.
That's not true actually. A fusion plant can leak highly radioactive tritium, poisoning anyone in the plant or relatively near. A magnetic containment plant can lose plasma containment and get a pretty giant explosion, definitely destroying the extremely expensive machinery, and likely also killing many inside the plant. This explosion would also throw parts of the radioactive reactor all around.
It's definitely nowhere near Chernobyl risks, but "if anything goes wrong it just stops" is not as guaranteed as is often made out.
>Don't you think that the fact that you can use sea water as input and you get hydrogen as output is a huge advantage over fission?
If it reduces the cost. But it doesn't seem to.
>Add to that the fact that there is no fukushima style meltdown in a fusion power plant. If something goes wrong, it just stops.
Same as the most recent fission plants.
> Same as the most recent fission plants.
How are these 2 things the same?
On one hand, you rely on a good design and execution to achieve an automatic stop. History has shown time and again that there will always be something that goes wrong: from the cracking rods of Chernobyl to the backup power at Fukushima.
On the other, if you don't design and execute perfectly, nothing works, so there is nothing to shut down. This is the definition of "fail safe".
It's like saying both a meteorite and a rocket will reach 500km/h in the atmosphere, but me it's pretty obvious one is much more likely to do so.
It is not worth investing money in, because it will never supply grid power: http://progressive.org/op-eds/let-cut-our-losses-on-fusion-e...
Here is another physicist warning about the hype just a few days ago: http://backreaction.blogspot.com/2021/10/how-close-is-nuclea...
It receives a pretty small level of funding, so I'm not quite sure there are many losses to cut.
$2.2bn over 5 years is about $1.50 per person per year. It's comparable to the funding for the CPB.
It’s not much compared with some other budget items, you’re right. But a billion here, a billion there, and soon you’re talking about real money.
ITER will cost about the same as the Manhattan project, around $21bn in 2021 $, and that's just one project. Total investment in Fusion globally is huge and the problem is at the moment there are multiple different feasible ways forward, and it's not clear which will pan out. There's huge risk of wasting large amounts of resources and time, even if we do eventually figure it out.
Creating conditions to split a heavy nucleus for 1 microsecond is much easier to do than fusing light nuclei steady state.
Yes of course, I know that. I’m not even saying the investment in fusion is a bad idea. I’m just pointing out that actually our investment in it is enormous and very risky.
> Modern fission plants are totally safe. Nuclear waste is basically a non-problem
Just removing that as part of the rhetoric around the tech makes fusion invaluable.
That is true actually. Seems silly but it's actually a serious benefit! The main issue with fission is that people have become irrational about it. Maybe we get a fresh start with fusion.
Unfortunately, a lot of the same environmental interest groups that halted the scaling up of fission also hate fusion.
It's best to think of fusion as a way to generate effectively unlimited amounts of energy, kicking in 50-100 years from today. This could be super useful for the long-term ambitions of human civilization - energy has been such a hard constraint for so long that people have barely thought about the amazing stuff we could do with an effectively unlimited energy supply.
For addressing climate change, it's likely to be too-little-too-late to bank on. But a century from now it'll be nice for cheap fresh water / agriculture / climate control anywhere on this planet, space elevators, interplanetary/interstellar travel, terraforming, cheap fresh water / agriculture / climate control on other planets, etc. This sort of stuff is incredibly energy-hungry and it's unlikely that renewables will be able to supply the requirements alone.
(It'd be awesome if one of the private fusion start-ups gets us there a lot faster, but this is what I'm projecting for now!)
> generate effectively unlimited amounts of energy
I don't understand where this concept is coming from. The best ever fusion power experiments so far have not even produced 1 miliwatt net electrical power. ITER, if it succeeds in its 30 year timeline, will not be even close to engineering breakeven (net power generation) - they estimate 0.57 output power/input power ratio - with DEMO hoping to break even 20 years later.
Why is there this bizarre idea that we'll jump from <massive effort to get even one miliwatt> to <unlimited power> with fusion?
It’s not unlimited power, it’s unlimited fuel.
The hype is coming from REBCO tape magnets which aren’t in ITER. Many consider ITER to already be obsolete.
This is like how computers used to take up whole rooms in the 50s but later could sit in the corner. Fusion takes up whole buildings (ITER) but the MIT ppl proved a magnet so that it can fit in just a room.
As our magnets get stronger the tokamaks can get smaller. Room sized tokamak is manageable for commercialization. Commonwealth Fusion Systems has a pretty clear path it seems.
There's a nearby fusion reactor that generates quite a lot of power. You may have heard of it.
Jokes aside, fusion would provide way more energy per fuel mass than any other source if we could only contain sufficiently hot plasma. Better magnets may be the key, as the other comment alludes.
But it's not true. Fusion power plants produce a steady stream of radioactive waste from the neutron bombardment. They can leak radioactive tritium. They can explode, spewing hot plasma and chunks of radioactive reactor walls in the area around the plant. The scope of the problem is nowhere near a fission reactor meltdown, but it's also not "gone".
>Modern fission plants are totally safe. Nuclear waste is basically a non-problem, especially with the most recent technology
Please elaborate on both. And I think we can all agree there's no such thing as totally safe, only risk management.
Gen2, even with weird designs (so Fukushima included) are individually safer than any coal plant ever built, and the whole generation will kill less people, even counting those dying in a shameful, unprepared evacuation, that the new "clean coal" plants (with flue gas discharge) built in the western world since the 2000s. Not taking into account the GHG emissions. Number of death/GW is in the favor of nuclear for any power station, even when counting dislodged people as "dead" (in this case, hydro is actually the 2nd most deadly)
For the nuclear wast beeing a non-problem: i don't agree, but i understand where he is coming from.
There is basically 3 type of nuclear waste: low-activity waste is waste that we could ignore, and the most present. radioactivity levels are what is find in granitic area. Often indirectly contaminated materials, or very long-lived isotope (radioactive decay is long, the the material is not very radioactive). It can still be dangerous and create radon gas if poorly stored (as do caves in granitic areas). We have no good answer to that. Maybe separate long=lived isotopes from the rest, store it, and reuse the contaminated materials after waiting a dozen years, mixing it with new cement or something.
intermediate-activity waste: still extremely dangerous, its often contaminated material (filter, pipes), or active (and dangerous) isotopes, with a half-life of up 500 years (i think the most present have an half-life of 200 years, and you need 10 cycles basically to be rid of it). Those are not direct fission byproduct (i don't think so, i don't remember exactly, maybe a small number is?).
High-activity waste: This is the real dangerous stuff. Those can stay hot for years. There is to kind:
- direct fission byproducts. Some degrade not in stable isotopes, but in the intermediate-activity waste, so even with a short half-life, they take as long as the intermediate ones to get rid of (since they degrade into it. If i'm over-explaining, sorry). Some degrade into stable heavy metals that also poison the environment, in a different way.
- transuranic elements. The graphite from Chernobyl could be counted in this category? (not sure, if an expert is here, can you infirm this?). I do not exactly understand this category, but its basically elements from the reactor core that are not fission products.
The reason why GP said "Nuclear waste is basically a non-problem" might be because we are able to re-use some the fission products, and to deactivate the rest. Both technologies are at an experimental stage, the first one could be in commercial use in the decade if China doesn't fail. And since the fission product decay is what's create the most troublesome waste (half-life between 100 and 500 years mean the wast stay dangerous for between 1000 and 5000 years), its a "non-problem".
I don't have the material on hand, i learned that in 2019. i could find it again if you wanted (probably mostly be in French, sorry), and to be fair, i might have oversimplified things i did not understand in the first place.
Since a commercial fusion reactor hasn't yet been developed, you can't argue that it is or will be the same cost per-megawatt as fission power. That's because you can't predict any advances in technology that make fusion easier or reduce the capital cost.
Based on a HN recommendation, I read this book: https://www.amazon.co.uk/Future-Fusion-Energy-Popular-Scienc...
The authors argue that ITER will get there and it's a matter of time, funding, and politics. SPARC might be able to get there around roughly the same time. Neither will be hooked up to the grid, but they will demonstrate the tech needed to make a viable fusion power plant. Unfortunately none of the other exciting fusion projects out there will be able to get off the ground due to fairly fundamental limitations.
If you ignore any tedious jokes about when fusion power will be ready, and assume it will be ready in a few decades, it's still a process that converts reasonable quantities of seawater into power, with no CO2 emissions, and is relatively safe compared to fission.
It won't be ready in time to reduce emissions enough to prevent catastrophic climate change. However, it can be ready soon enough to power the devices we'll need to sequester CO2 from the atmosphere once we've reduced our emissions to the point of diminishing returns.
After the concept has been demonstrated, there's plenty of scope for improvement which will make it better and cheaper. On the other hand, the price of oil will increase as emissions taxes are introduced (I hesitate to say that we'll run out of reserves).
There's a lot more mileage in fission technology that what's commonly deployed for power, but the new types of reactors needed make it far easier to produce weapons(). Also, although fission technology is mature and safe, the human factors around it are not, which will still lead to accidents, contamination, and deliberate theft.
() Fusion reactors would also make it possible to breed fissile material since they are a neutron source but it would be slower and easy to detect.
>What's the big benefit of fusion that makes it worth investing so much money?
4-20 times the energy density of fissionable materials[0] and fuel that's the most common element in the universe.
[0] https://en.wikipedia.org/wiki/Energy_density#In_nuclear_reac...
And what is the benefit of that?
>And what is the benefit of that?
I'll leave that as an (fairly obvious) exercise for you, dear reader.
> Modern fission plants are totally safe
Unless there's a war. Unless corruption leads to poor management of the plants. Unless nuclear waste is mismanaged. Unless there is an earthquake or tsunami of completely unexpected intensity.
> Unless there's a war. Unless corruption leads to poor management of the plants. Unless nuclear waste is mismanaged. Unless there is an earthquake or tsunami of completely unexpected intensity.
No for mismanagement, earthquake or tsunami, the gen3 are completely safe, all security mesures are passives, unless the fault is directly on the core, it will fail gracefully. Irradiated water might leak, but to be fair, underground water in granitic areas are more irradiated than the fission product pool.
Issues are war (and in this case, direct sabotage from an actor with actual knowledge, or a direct hit into a functioning reactor, so pretty much on purpose strike. I wouldn't be afraid of terrorism) and waste.
or corrosion of containment vessel, or an airplane strike…
http://green.blogs.nytimes.com/2010/04/21/critics-challenge-...
>Modern fission plants are totally safe
Ha what? The number of flaws in any system is unknowable. We thought the Fukushima Daiichi reactors were safe and then what happened? Meltdown because the backup generators were flooded.
That statement transposed to software engineering is like saying "we use Kubernetes so we have 24/7 uptime".
Assuming there are multiple breakthroughs on the research, design, and scale-up phase, fusion will only help us in a couple decades, put on the brakes is a 2020/2030s task. Putting on the brakes means slowing down, which means decarbonizing power, transport, industry, and agriculture, amongst other things. We don't need fusion to do that, we need to transform our current system. Fusion could be nice as a future-fuel, perhaps it could power carbon sequestration efforts. But unless we put on the brakes NOW with what we have, this car is going to crash.
Fusion could be nice as a future-fuel, perhaps it could power carbon sequestration efforts
Agreed, that seems like the biggest opportunity for fusion to fit into climate change.
Best time to invest into fusion research was 50 years ago. Second best time is now.
Nuclear fission is one of a few (if not the only) viable ways to have significant positive impact on climate change short-term (20 years).
Small rant on nuclear waste. I don't think it's a problem. I think it's a solution to fuel future generations of reactors (50+ years). I'd go as far as assume that e.g. Finland could import nuclear waste and store it in that new state-of-the-art nuclear waste repository. They would make money now to store the waste, and then make money eventually when tech is there to reuse it and generate power.
No. The car will still be running even if we fully stop right now. There is an excess of carbon in the atmosphere, there are feedback loops that are emitting carbon due to the already existing warming, you don't shutdown the greenhouse effect with just a halt or slowdown of emissions because what is already there will keep doing its job.
What you can do switching to nuclear (in some industries, at least) is to not increase as much as previous years what we add to the problem.
It's not stopping, nor slowing down or keeping the current speed, but just accelerating a bit less than before.
Massive carbon capture is needed (orders above the gigantic amount that is added each year, because you need to take out the carbon emitted in the previous years too, and there is the feedback loops playing too), along with bringing new emissions sharply down. And all of that at least for many years after reaching below preindustrial carbon levels (global temperature should drop enough to turn off the positive feedback loops).
Nuclear fission is good enough, available right now, causes much fewer deaths than the alternatives, does not pollute the atmosphere, and accidents are extremely rare and nowhere near as dangerous as they've been portrayed. To wit, Fukushima: 1 dead from the nuclear accident, compared to 10000 from the tsunami.
All good qualities, but there's one problem - cost and time to rollout.
Even China, which internally can impose any policy it wants, can't build them fast enough to match e.g. wind in terms of GWh delivered. That has been the case since 2012 or so.
> All good qualities, but there's one problem - cost and time to rollout.
Well those are only problems because the people who benefit from climate change, like politicians, UN and organizations like extinction rebellion, do not want the problem solved.
Fukushima didn't kill many people, but it's projected to cost $187b to clean up.
Chernobyl has supposedly cost over $300b inflation-adjusted. Gorbachev wrote that in his opinion, it was a major contributor to the collapse of the USSR. Both figures are from Wikipedia.
Fission is safe, but even one accident can wipe out decades of profits. Is it still cost-effective when considering that?
> but it's projected to cost $187b to clean up.
That seems quite high.
> Fission is safe, but even one accident can wipe out decades of profits. Is it still cost-effective when considering that?
You can put a number on the cost of the Fukushima disaster, but you're not putting one on that of other power sources. Coal burners make the whole world pay, nuclear operators have to deal with their own shit. And yes, I'm not counting Chernobyl-type accidents, because while it would be foolish to claim that events like Fukushima will never happen again, it's equally foolish to not recognize that dodgy old dinky soviet plants with no passive safety measures whatsoever are a solved problem.
I'm not disputing that nuclear is better than coal, but that's quite a low bar. Usually nuclear is compared to solar (with storage), wind, and hydro. These don't have the pollution downsides of coal. And while dams can fail catastrophically, I don't think the cleanup costs approach those of a nuclear power plant failure.
Probably not. ITER takes 440 megawatts of total power to generate 500 megawatts of power, at the cost of many years of development & billions of dollars. [1]
[1] http://backreaction.blogspot.com/2021/10/how-close-is-nuclea...
ITER means International Thermonuclear Experimental Reactor. It's not supposed to be useful. It is a prototype.
And yes, it costs a lot, but if they succeed, it would solve so many problems, it would be worth it.
And for scale, compare this to the amount of money being spent on, I don't know, the video game industry[1].
[1]: https://web.archive.org/web/20190509014637/https://newzoo.co...
> ITER takes 440 megawatts of total power to generate 500 megawatts of power
not 500 MW of usable power. Have a watch of https://www.youtube.com/watch?v=LJ4W1g-6JiY
Yeah, you're right. I forgot about the heat efficiency. Even if it generated the full 500 megawatts, it wouldn't even be close to practical.
Shouldn't we be betting for SPARC from MIT and not ITER?
No, read further down in that article. The gain is actually 0.57, certainly not > 1. And that is the plan, not anything demonstrated.
From your article it's more: "Okay, so ITER will have delivered in that full demonstration that we could have okay 500 Megawatt coming out of the 50 Megawatt we will put in."
That's 50 MW going into the plasma. But they have to draw 440MW from the grid to deliver this power to dump those 50 MW into the plasma (lasers are extremely wasteful).
Also note, the 500MW are the power of the plasma - in the best case scenario, maybe 50% of that could be converted into electrical energy, the rest will be lost as heat.
So grid-to-grid, they will be taking out 440MW of power and putting back in 250MW. Except that is useless, so they didn't even bother with a turbine the full 500MW of plasma power will have to be vented as heat in ITER itself (DEMO will take over, and aims to deliver net power generation ~20 years after ITER is successful).
No, it’s less. Please read the whole thing. The claimed gain is only 0.57.
Nuclear fission can
Sadly, nuclear fission power that works at scale - both on the technology and social sides - seems to be mostly beyond the capabilities of current human societies.
No it isn't. It's worked for decades and the new forms of it are even more effective. Other countries are doing it with great success.
If even fission is too hard, wouldn't fusion have just the same problem but 10x harder?
Fusion's problems are very different from fission's problems.
Fission arguably went from the first serious attempt at a reactor (U of Chicago, Dec. 1942, successful self-sustaining reaction) to powering a large, high-performance naval vessel (USS Nautilus, Jan. 1955, in service for ~25 years) in 12 years. Its technological and social problems are very complex, but pretty well-known.
Fusion experts have yet to achieve any self-sustaining reaction - in spite of numerous, well-funded attempts going back ~60 years. Roughly speaking, there seems to be no plausible prospect for fusion being a viable power source for anything outside of a lab. So its technological problems amount to "not actually possible", and its social problems amount to "very cool waste of money".
> Sadly, nuclear fission power that works at scale - both on the technology and social sides - seems to be mostly beyond the capabilities of current human societies.
Well yes, because people who benefit from climate change do their utmost to ensure this is the case.
Which explains why grid-scale hydropower, solar power, wind power, etc. have all failed, new construction has all but ceased, and existing installations are being closed down...?
> Which explains why grid-scale hydropower, solar power, wind power, etc. have all failed, new construction has all but ceased, and existing installations are being closed down...?
This is news to me, this is not the case where I am, but sucks for you, just goes to show that people don't want to solve the problem. Where I am hydro power works well and most of our power comes from that, but that does not change the fact that many people fight as hard as they can to stop new hydro from being constructed.
In a fission reactor, I know the energy goes into the water, which creates steam and that turns a turbine. But it looks like fusion reactors use a near vacuum and high powered magnets. Once two atoms actually fuse, where does that energy "go"? Does the new helium atom just bounce around the containment unit? How do we actually extract meaningful energy from such a closed system?
Edit: https://en.wikipedia.org/wiki/ITER for visuals.
In the same way. Most proposed fusion systems use deuterium-tritium fusion where a significant amount of the energy is carried away as neutrons, so direct energy conversion wouldn't be possible anyway.
From the article you referenced:
> ITER will not produce enough heat to produce net electricity and therefore is not equipped with turbines to generate electricity. Instead, the heat produced by the fusion reactions will be vented.
So in a fusion plant, the particle energy would turn into heat (by the particles interacting with matter), this would heat up water (or some other carrying fluid), turning a turbine that produces electricity. See also https://en.wikipedia.org/wiki/DEMOnstration_Power_Plant which contains some diagrams showing just how that would be done.
More exotic reactions (e.g. p-B11) have been proposed, where almost no energy is in the form of neutrons. Theoretically, you could then use electrostatic devices to capture the energy directly without any of the mess with Carnot efficiency. However, getting p-B11 fusion going is much harder than d-t.
Ahem...
Heat is extracted to run a turbine, as with any reactor.
Where/how does the heat extraction take place? Are they planning to put water pipes in the walls of the confinement unit? I'm struggling to understand because in the diagrams I see a powerful magnetic field containing the particles, and then a near vacuum. Those two things alone must make heat transfer very difficult, no? I don't see where the produced energy gets extracted.
Sure, but how? What physical processes are being used? Most of us can understand how hot fision encased in water turns to steam and runs a steam engine (even if the reality is still quite complex). But how does the thin-plasma get converted to steam?
Fast neutrons leaving the confinement field. Most of the energy goes into the blanket between the first wall of the vessel and the confinement coils. This blanket is made of Be and Li. Be to act as a neutron multiplier and Li to breed tritium. The Li fission is actually energetically favorable and is a significant percentage of the power output. It is also the source of tritium fusion fuel. The byproducts of these reactions are helium. Liquid lithium can also double as a coolant in an efficient (high temperature differential) thermal cycle.
The rest of the power gets dumped into the divertor. This is a pretty violent section of the hull that has an enormous power density slamming into it (in ITER it will be similar to an atmospheric re-entry vehicle). There are games to play here though and the strike points can be blown up in size.
In both cases energy comes from neutrons. In the case of a fusion reactor, some neutrons escape plasma containment, presumably then heat up something outside, then heat transferred to water as usual.
This article asks the wrong question.
"Can Nuclear fusion bail out our ship before it sinks?" No.
"Can Nuclear Fusion help us re-float our ship after its sunk?" Maybe.
Can captured space alien technology based on element 115 help solve climate change? It's about as likely to generate real commercially usable amounts of power in the next decade.
At this point, we don't have new fission plants being built, and we're converting all the coal plants to run on natural gas, which is just going to jack up the prices for consumers who use it for heat.
The time to fix this was 5 decades ago.
When a headline asks a question, the answer is almost always “no”.
If you're interested in fusion power check out Robert Bussard's tech talk on his design: https://www.youtube.com/watch?v=FhL5VO2NStU
The claims on nuclear fission being just around the corner are wildly exaggerated. Sabine Hossenfelder has a great video [1] on this topic. I want fusion to be real too, but focussing on small scale fission and solar is probably a better idea.
No. Almost all electricity that we generate will eventually turn into heat and get released into the atmosphere.
Even if nuclear had 0 environmental impact during production, which is absolutely not the case, we still must cool down the planet.
We need energy sources that work by CAPTURING energy that otherwise would be turned into atmospheric heat.
SPARC is going to be relatively small in size. If they can make the commercial reactors as small as SPARC then they can be created in a factory. Which will make roll out and cost much better than fission.
SPARC will also not produce net power gain, as far as I know. They are planning to achieve "breakeven", which is energy going into plasma < energy of plasma, promising Q > 2, with an optimistic expectation of Q ~ 10. But best estimates for plasma energy -> electrical energy conversions are 50% efficiency, and energy going into plasma is typically many times smaller than the amount of energy drawn from the grid (couldn't find any numbers for SPARC).
SPARC doesn't seem to publish such numbers, but ITER, which is aiming for Q ~ 10 is going to be nowhere near to generating net energy, so SPARC's 2 < Q < 10 is unlikely to be able to do it either.
Edit: ITER is also going for Q~=10
No, Fusion can not put the brakes on climate change. It is the best long term option for generating heat, but the problem is not about what we add, but instead about what we remove.
Carbon Capture is what will matter. Carbon taxes are an interesting attempt at political solutions, but this requires coordination between Russia, CCP, and the USA. We need something that can be done despite what other foreign powers can be made to do, lest we want to wage WW3 over this.
Carbon Capture is also proportionately underfunded compared to renewables. Global warming is not something that will stop when we stop being bad; it has momentum. Greenhouse gases are like a blanket we’ve been wrapping around ourselves. We have to unwrap to get back to normal: carbon capture.
I hate things like this.
Climate change is an emergency, one that we're far behind on tackling. Talking about future technologies that are many decades away (if ever) is the opposite of helpful.
Imagine in 1943 the headline:
"Can hypersonic missiles put the brakes on Hitler's Army?"
Well, nukes (which didn't exist then) sure put the brakes on Japan's military.
Yes, but nukes weren't decades away from being deployed in active intended use-case. Fusion is at least 10 times further-off right now than nukes were early in the war. That's why I pointed to a modern weapon like hypersonics, and not nukes - because we're talking about many decades.
And more to the point, nobody waited for nukes. The allies tackled the problem with the tools they had available at the time, and made use of the nukes when they were ready.
edit: the comparable timeline would be "currently approved power plants that are planning construction could put the brakes on climate change", I mean, if it were true. Because deadlines for substantial impact on climate change are "next few years, decade or two tops", and fusion will be ready far too late.
I agree that we should be rolling out as many modern, small scale fission reactors as possible, right now, in order to deal with CO2 output. But, at the same time, I think we should pursue fusion with the same gusto that we currently direct towards blowing up 3rd world countries. Also, recent advances might herald fusion in less time than you'd think: https://news.mit.edu/2021/MIT-CFS-major-advance-toward-fusio....
Why would any government or international organization want to put the brakes on Climate change if it is the single biggest reason to increase their power? Do people think it's coincidental that the people who shriek loudest about climate change also shriek loudest about nuclear? And the thing is, I know whoever wrote this drivel for the new yorker knows better.