101–110 of 282 posts
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Meaning, why can't we just spend an unlimited amount on everything we think we might like?
Who says we can't? Money is a social construct.
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Compare that to a simple molten salt fission reactor. It will simply never be cheaper.
Molten solt reactors do not solve the problem of nuclear waste. It is very expensive to deal with it as it has to be stored for hundreds of years unless some technology would appear to separate that cheaply. Fusion produce like order of magnitude less radioactive waste which will be short-lived. Plus a fusion plant can be very quick to start and shutdown or throttle down which is very useful for base load.
Fusion solves a minor problem of fission while making the major problem worse. It's a great example of misplaced focus.
Cooling down the magnets of a fusion plant is not a quick process, btw. Hell, just getting a fusion plant built with RAFM steel up to operating temperature is a delicate process. Once irradiated, the temperature window that material can operate at is rather narrow (300 C to 550 C; below that it's too brittle and above that it creeps.)
Fusion has no practice reason to exist compare to advanced fission. The improvements in energy density are not really relevant factor at that scale, meaning the difference from oil to fission, and oil to fusion doesn't really gain you much. Fusion fuel cost over the long term is likely more expensive then a fission fast breeder (not to mention a potential of thorium thermal breeder). Is a fusion reactor going to be c…
Isn't fusion safer? If fusion was a viable option for countries that are phasing out fission like Germany then it could solve a lot of problems especially decreasing reliance on gas
In general, fission is very safe and next generation fission plants in development are incredibly safe. To a point where you have to really be Micheal Bay to come up with a scenario where radiation is escaping the exclusion zone.
Germany does not have a safety problem, they have a culture problem. This is driven by a 70s anti-nuclear war agenda that basically makes civil nuclear plant = nuclear weapon argument. I have lived in Berlin and the amount of anti-nuclear nonsense you see there is amazing. Anti-nuclear foot mats are common.
Fusion is not a practical viable option in the next 2 decades likely more.
You can right now go to South Korea and order 10 1GWh nuclear plants for the next decade and probably much more. Germany could have started built nuclear 2 decades ago and they would be as or more carbon free then they are now.
Next generation fission plants are going threw regulatory process in a number of places and I am not informed on China. Canada is your best bet for a internationally recognized regulator to license an GenIV plant. The US is cooperating with Canada and hopefully will issue dual-licenses.
Most of these companies have a hard time getting money, the process could speed up if other countries really invested in this tech.
See the current state here:
https://nuclearsafety.gc.ca/eng/reactors/power-plants/pre-li...
The furthest along are Terrestrial Energy with a Molten Salt fast reactor. They have been in 'Phase 2' for a few almost 4 years now and should finish that relatively soon. This is the furthest along any non-research GenIV design has ever come as far as I know.
Hopefully by the end of this decade we will see some actually operating.
Technology wise this could have been done long ago, but the Canadian regulator is really the first to be so forward thinking. In the US non of this would have really been possible.
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The catastrophic global warming you mention is not a boolean. It can always get worse, with the planet becoming more and more inhospitable, up to the point where mankind can't survive (wet bulb temperature permanently above 35c --> everyone dies without air conditioning) - and beyond. Even if it's too late to avoid it completely, it still makes very much sense to work on not making it even worse. Suggesting to abando…
Should we build N Wind turbines or blow the money on more fusion research? I would guess that we need to keep fusion research alive but the real bulk of the money should be for things that will work now.
I'm a big believer in wind and solar, although their intrinsically intermittent operation causes me to also worry about baseload power options, and nuclear fusion is the most attractive and promising development in that field.
I think it's stupid to look at one part of the solution and not at the other(s).
Skeptical. This video by Sabine clearly explains why a lot of these fusion research claims are dubious with a focus on ITER and JET: https://www.youtube.com/watch?v=LJ4W1g-6JiY
That Sabine has a point that some media outlets miscommunicated the Qtotal, it does not mean every article that does not mention Qtotal is somehow a scam. Qtotal is only relevant for project in which achieving a positive Qtotal is actually a goal, which it isn't for any of these projects.
What Sabine doesn't mention is what the theoretical limit of Qplasma actually is. ITER was explicitly designed for Qplasma>=10 to save costs. There's no other reason why Qplasma couldn't be higher. It's just money that is the limit.
People quoting Sabine should get this in their head, ITER was not designed for generating electricity. Its Qtotal is intentionally lower than 1. Yes there have been journalists who got important details in their articles wrong, but anyone who knows anything about these reactors is not being mislead by the ITER or JET experiments.
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The energy flux density in the most compressed plasma imaginable is orders of magnitude less than in fissile uranium. So, to match power out, it has to be big. Really, really big. And a fusion reaction chamber is a much more expensive affair than a fission pile: super high-tech materials and construction, enormous magnets (blasted by the hot-neutron flux output), piping for thousands of tons of melted lithium that ha…
This was with previous designs of fusion reactors. Read about proposed Ark and currently constructing Spark reactors. By using stronger superconductive magnets it was possible to reduce the size of the plant by order of magnitude. Spark even has a chance to get to Q>1 before ITER and it’s chamber is less than 2m in diameter. Plus it is possible to replace its parts without disassembling the whole reactor. [1] - https…
Yes, making magnetic fields stronger can give one higher power density than ITER. But one runs into a limit because of power density at the wall. Once you're at that limit, higher magnetic fields don't really help.
ARC's volumetric thermal power density (volume of reactor, not of the plasma) is just 1/40th that of the primary reactor vessel of a commercial pressurized water fission reactor.
60% of the mass of an ARC reactor is in the steel structural supports for the magnets, so it's about at the upper limit for steady magnetic fields in a fusion reactor.
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It is much simpler than that: fission is mature tech; its cost is not on the way down. Solar costs are still in free fall, wind almost as much so. The cheaper those get, the less competitive fission gets, just standing still. The corruption tax on fission projects just exacerbates its structural problem.
most of that cost is politically based not technical
As much as I enjoy reading this news. It is feels heavily sensationalized. "Smashes" the energy record. We're talking about a fusion generator here, that after 25 years of work, now manages to output 'double' the energy, to 59 MJ in 5s -like 20 MW- while requiring 180 MJ input power. Somewhere hidden in the article is the news that this could mean a input/output ratio of 10 in a full scale reactor, but that's also so…
JET is a 1980s research project into how to contain a plasma and squish it enough to achieve fusion at all, not a practical generator. It doesn't have superconducting magnets, it runs on big lumps of copper, with limited cooling and no way of recovering output power.
In the latest run, they achieved fusion and kept it running until JET ran out of power for its magnets. The plasma didn't touch the reactor walls, didn't destabilize, didn't crap out in any of the numerous other ways. They had to shut it down before it overheated and burned out.
(I've been reading reports for a while about the use of massive amounts of computer power -- and deep learning -- being necessarily to stabilize plasma in a reactor. That seems to be what this demonstrates.)
This is probably JET's swan song. They've pushed it as far as it can go; also, the D-T reaction produces surplus neutrons so tends to generate radioactive waste via secondary irradiation of the reactor core -- which makes it hard to get inside and fiddle with it.
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Fission getting more expensive is tied to the very lucrative fully-legal corruption industry. Once a fission plant construction project is started, the money starts flowing, and is practically impossible to stop. If it is ever finished, the money would stop, and nobody actually involved wants that ever to happen, at least not until their kids graduate college. So the project blows through deadline after deadline, and…
Wow this is brutal but feels like it's correct. What a frightening state of affairs. Is the construction industry really so corrupt? Is government and industry unaware or unwilling/unable to detect this earlier and stop it?
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Molten solt reactors do not solve the problem of nuclear waste. It is very expensive to deal with it as it has to be stored for hundreds of years unless some technology would appear to separate that cheaply. Fusion produce like order of magnitude less radioactive waste which will be short-lived. Plus a fusion plant can be very quick to start and shutdown or throttle down which is very useful for base load.
Nuclear waste is not the major problem with fission, capital cost is. Fusion solves a minor problem of fission while making the major problem worse. It's a great example of misplaced focus. Cooling down the magnets of a fusion plant is not a quick process, btw. Hell, just getting a fusion plant built with RAFM steel up to operating temperature is a delicate process. Once irradiated, the temperature window that materi…
If you can build a nuclear plant with 500MW output and reduce the amount of concrete needed by significant factor, all of a sudden your are quite competitive.
Just for comparison, this is one of the furthest along commercial GenIV projects designs:
https://www.youtube.com/watch?v=1pZC_ajI8Hs
No massive cooling towers. No gigantic containment cylinder. No gigantic low-pressure steam turbine.
In a PWR the core containment vessel is incredibly expensive and can only be built a few places, but its actually not the cost driver. Even so, compare to those, modern GenIV core vessels are vastly cheaper.
Not having to weld 8 inch gigantic steel vessels is far easier. See:
