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Founders of Amazon and Microsoft funding little-known fusion energy companies

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Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#41

Post by GunboatDiplomat »

DennisP wrote: post #40
refurb wrote: post #37

Earlier quoted context omitted.

you can't keep 20th century energy growth going for much more than another century or two before waste heat alone causes catastrophic climate change. That seems unlikely to me, but I'd be happy to be proven wrong. I would imagine that all of the waste heat produced through the world's economy is several orders of magnitude lower than the sun. Like less than 0.0001%.

True, and waste heat is a far smaller contribution to warming than greenhouse gases. But exponential growth gets impressive after a while. At 2.3% growth per year, we boil the oceans in about 400 years: http://physics.ucsd.edu/do-the-math/2011/07/galactic-scale-e... Whether this is physically or economically realistic is another matter. I tend to think that long before waste heat is an actual problem, we'll either tr…

Well, that assumes we don't move manufacturing processes off planet. Which is more realistic when nigh-unlimited energy (fusion) is available. With that, you can do cool things like launch loops or even a space fountain.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#42

Post by hokuriku »

I'm really proud of General Fusion, they're a rare Vancouver success story. And good on the Trudeau government for backing them!

I just hope that Christy Clark doesn't sabotage GF with her goal of turning mining, LNG, fracking and real estate into BC's economic engines.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#43

Post by YZF »

tachim wrote: post #39
YZF wrote: post #24

I have some friends at General Fusion and I've been following them relatively closely from the beginning. I had an opportunity to invest some in the beginning and decided not to - mostly because the problems they're trying to solve seemed so hard. They've pivoted a little bit on their approach since then. In the beginning it was all about focussed pressure waves. Now they're starting with plasma. Fusion is really har…

How does the design process for these reactors work? How much design is done in simulation vs experimentally and how high-fidelity are the simulations?

From what I know a lot is experimental.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#44

Post by iaw »

Serious question for those with actual knowledge of Controlled Fusion Economics:

Does the smaller size of this reactor design mitigate the challenges that the Tokamaks face with material radioactivity? With the level of neutron bombardment those pistons undergo what material can they be made of to assure an economically viable operational lifetime?

I remember this being one of the bigger challenges for all of injector and heating equipment in Tokamak designs. After a point the devices are composed of different radioactive isotopes and have to be replaced/disposed of, making the economics... challenging.

Is it possible for this project to be successful without a Materials breakthrough? I don't think the Physics challenges are insurmountable with enough time, but finding new materials can be a rabbit hole.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#45

Post by mng2 »

tachim wrote: post #39
YZF wrote: post #24

I have some friends at General Fusion and I've been following them relatively closely from the beginning. I had an opportunity to invest some in the beginning and decided not to - mostly because the problems they're trying to solve seemed so hard. They've pivoted a little bit on their approach since then. In the beginning it was all about focussed pressure waves. Now they're starting with plasma. Fusion is really har…

How does the design process for these reactors work? How much design is done in simulation vs experimentally and how high-fidelity are the simulations?

This is not my field (just an enthusiast) but consider that a typical fusion plasma has a density of 10^20 particles per cubic meter. Even if your plasma is 1 cubic centimeter, that's still 10^14 particles! Thus a full-on EM simulation, where every charged particle interacts with every charged particle, is not practical. A full-scale simulation is still unrealistic even if you typically cheat by breaking the problem up into cells and ignoring the Coulomb interaction beyond cell boundaries.

Fusion machine design is a combination of hard-won experimental knowledge and theoretical guesswork. I'm skeptical of the current wave of fusion startups simply because they don't have the weight of the decades of experimental work that have gone into tokamak research. But hey, they might make a breakthough, who knows.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#46

Post by paulsutter »

iaw wrote: post #44

Serious question for those with actual knowledge of Controlled Fusion Economics: Does the smaller size of this reactor design mitigate the challenges that the Tokamaks face with material radioactivity? With the level of neutron bombardment those pistons undergo what material can they be made of to assure an economically viable operational lifetime? I remember this being one of the bigger challenges for all of injecto…

Aneutronic fusion[1] releases 100x fewer neutrons, but requires 10x higher temperature, among other challenges:

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

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#47

Post by Natsu »

paulsutter wrote: post #46
iaw wrote: post #44

Serious question for those with actual knowledge of Controlled Fusion Economics: Does the smaller size of this reactor design mitigate the challenges that the Tokamaks face with material radioactivity? With the level of neutron bombardment those pistons undergo what material can they be made of to assure an economically viable operational lifetime? I remember this being one of the bigger challenges for all of injecto…

Aneutronic fusion[1] releases 100x fewer neutrons, but requires 10x higher temperature, among other challenges: [1] https://en.m.wikipedia.org/wiki/Aneutronic_fusion

I thought it was also proven that it couldn't be energy positive.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#48

Post by iLoch »

I know Michel Laberge, he's from my home town of Bowen Island, BC. I went to school with his son, and my earliest memory of his mad scientist work was when his son brought in a mechanical hand controlled by a glove for his grade 6 science project. I think I was experimenting with lemons as a power source...

Of course we didn't learn until much later that he had rented the old gas station in the middle of town to conduct experiments with nuclear energy.

I still believe General Fusion's approach to be the most practical of the solutions I've seen. I'm continually following their progress, and am hoping for great news to come from them. I would love to be able to tell this as the story of how we accomplished nuclear fusion.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#49

Post by namlem »

refurb wrote: post #37
semi-extrinsic wrote: post #30

Earlier quoted context omitted.

There are also fundamental thermodynamic limits that you hit at some point. All production and usage of electricity produces waste heat, it's unavoidable (see Carnot). Even neglecting global warming, you can't keep 20th century energy growth going for much more than another century or two before waste heat alone causes catastrophic climate change.

you can't keep 20th century energy growth going for much more than another century or two before waste heat alone causes catastrophic climate change. That seems unlikely to me, but I'd be happy to be proven wrong. I would imagine that all of the waste heat produced through the world's economy is several orders of magnitude lower than the sun. Like less than 0.0001%.

Waste heat could possibly replace natural gas for heating. Eventually that won't be enough, but I'm sure by the time it becomes a problem we'll figure something out.

Re: Founders of Amazon and Microsoft funding little-known fusion energy companies

#50

Post by DennisP »

GunboatDiplomat wrote: post #41
DennisP wrote: post #40

Earlier quoted context omitted.

True, and waste heat is a far smaller contribution to warming than greenhouse gases. But exponential growth gets impressive after a while. At 2.3% growth per year, we boil the oceans in about 400 years: http://physics.ucsd.edu/do-the-math/2011/07/galactic-scale-e... Whether this is physically or economically realistic is another matter. I tend to think that long before waste heat is an actual problem, we'll either tr…

Well, that assumes we don't move manufacturing processes off planet. Which is more realistic when nigh-unlimited energy (fusion) is available. With that, you can do cool things like launch loops or even a space fountain.

Hence my last paragraph. But alternative launch systems is a good point.
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