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Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

imperial.ac.uk

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Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#91

Post by thomasahle »

jhallenworld wrote: post #84
rfrey wrote: post #61

Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

Study this: https://www.lazard.com/perspective/levelized-cost-of-energy-... Ignoring storage: it makes no sense now to build anything but wind and solar. Only the marginal cost of gas is cheaper (meaning existing plants, not new ones). Including storage: conventional is still cheaper, but not by much (within a factor of 2): $81 for PV+storage vs. $44 for gas combined cycle. We should put more resources into storage n…

This is a great resource!

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#92

Post by adrianN »

brightball wrote: post #86
vilhelm_s wrote: post #69

Earlier quoted context omitted.

Natural gas plants are cheap but they cause global warming, so soon we will not be able to use them. For example, the U.S. target is to have zero carbon emissions from electricity generation by 2035, and zero carbon emissions at all by 2050.

Their carbon emissions are still dramatically lower than those of coal and oil. There are bigger fish to fry than NG. NG is likely going to be a critical transitional fuel for the planet to depend on while we get to more abundant renewable options, grid batteries and nuclear/fusion/thorium.

With NG you also have to take into account leakage from extraction and transport. Methane is a pretty strong GHG. I've heard that if you take that into account NG is not that much better than coal.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#93

Post by willis936 »

tootie wrote: post #34
mlindner wrote: post #25

Earlier quoted context omitted.

Sabine actually is completely misleading and misconstrues a bunch of facts. None of these plants are even attempting to have real energy breakeven and spend a ton of energy supplying experiments and unrelated support equipment. They don't even have a method of capturing energy as that's not the point as it would make it harder to test the physics. Additionally these plants have high amounts of "startup energy consump…

I think her meaning is pretty clear and correct. As much as plasma breakeven may be the entire goal of ITER it's absolutely setting them up for a badly missed public expectation. The day they declare net positive output, the world will ask when we can start building infrastructure and the answer will be "30 more years" and then they'll get their funding yanked forever.

>As much as plasma breakeven may be the entire goal of ITER

Who gave you that impression? They were lying. The goal of ITER has always been to study burning plasmas and experiment with solutions to problems that a reactor-grade MCF machine faces.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#94

Post by Fordec »

rfrey wrote: post #61

Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

> We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada.

Was this Canada specific? A country with both very abundant native oil & gas and abundant hydro energy with nuclear power plants in place to boot.

Not every country in the world has such abundant energy sources on tap.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#95

Post by willis936 »

ckuehne wrote: post #42
mlindner wrote: post #25

Earlier quoted context omitted.

Sabine actually is completely misleading and misconstrues a bunch of facts. None of these plants are even attempting to have real energy breakeven and spend a ton of energy supplying experiments and unrelated support equipment. They don't even have a method of capturing energy as that's not the point as it would make it harder to test the physics. Additionally these plants have high amounts of "startup energy consump…

I think your statement "Once you have plasma breakeven you have a self-sustaining heater basically" is false. According to Wikipedia [1] - if I interpret it correctly - the fusion energy gain factor from plasma must be 5 (!) to have a self-sustaining heater: "Most fusion reactions release at least some of their energy in a form that cannot be captured within the plasma, so a system at Q = 1 will cool without external…

Fusion begets fusion. ITER plans to have high-intensity, relatively short Q=10 shots. If the plasma heats itself then it doesn't need much heating. This sudden focus on Q is clearly the result of one vocal non-expert not understanding the field and everyone listening to them like they have something valuable to teach.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#96

Post by coolspot »

kragen wrote: post #54

Does this mean you can now build a hydrogen bomb without uranium or plutonium? If not, why not?

Man-made nuclear fusion is not self-sustaining, requires massive infrastructure to ignite very little of material.

Nuclear fission of unstable isotopes is self-sustaining chain reaction that converts a lot of matter into energy without much of hardware - just put some sub-critical mass of Plutonium into a sphere lined with conventional explosives.

See also: https://en.wikipedia.org/wiki/Pure_fusion_weapon

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#97

Post by beachy »

f00zz wrote: post #59
ph4 wrote: post #46

So is the goal just to fuel our current patterns of consumption and development with fusion, or nuclear, or whatever?

A lot of stuff becomes feasible with free unlimited energy. For instance, carbon air capture (could even become a protein source) and green hydrogen (for applications like production of iron via direct reduction, so we can finally get rid of blast furnaces).

I can't help feeling we'll find new ways to soak up that energy.

Ad tech will start segmenting right down to the individual customer, burning thousands of watts to work out how to entice then to spend $20.

Perhaps raw heat, rather than the indirect heat effects of global warming will be our next challenge.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#99

Post by jhallenworld »

Andrew_nenakhov wrote: post #90
jhallenworld wrote: post #84

Earlier quoted context omitted.

Study this: https://www.lazard.com/perspective/levelized-cost-of-energy-... Ignoring storage: it makes no sense now to build anything but wind and solar. Only the marginal cost of gas is cheaper (meaning existing plants, not new ones). Including storage: conventional is still cheaper, but not by much (within a factor of 2): $81 for PV+storage vs. $44 for gas combined cycle. We should put more resources into storage n…

"We should put more resources into breeding faster horses now, internal combustion can wait." - someone in late 19 century.

Hah, well what was the rate of progress on breeding faster horses vs. internal combustion in the late 19th century? I don't imagine that the progress rate was very high for horses..

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#100

Post by not2b »

We're still a very long way off. Sabine Hossenfelder has a good explanation of what's wrong with most reporting on progress toward fusion:

http://backreaction.blogspot.com/2021/10/how-close-is-nuclea...

edit: not sure why this was downvoted, it's directly relevant and the video and transcript discuss this experiment. It quotes Arthur Turrell: "This phenomenal breakthrough brings us tantalisingly close to a demonstration of 'net energy gain’ from fusion reactions – just when the planet needs it." But this comes close to getting Qplasma to be 1, which is about a factor of 50-70 lower than getting Q to be 1 (total power into the reactor vs usable power out of the reactor).

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