ITER: World's largest nuclear fusion project begins assembly • Hacker News Board

Re: ITER: World's largest nuclear fusion project begins assembly

#61

Post by mytailorisrich » Tue, Jul 28, 2020, 9:28 PM UTC

andrepd wrote: post #39

usui wrote: post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

I'm also a fusion power fanboy but >nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is a…

Hydro is extremely restricted because of geographical and environmental constraints. Solar is also quite constrained by lack of large-scale storage and environmental concerns, and just by the weather. Same goes for wind.

Keeping in mind that electricity production has to increase significantly to absorb the shift from ICE to EV vehicles I would tend to agree that there is no way to meet demand without nuclear even if renewables are, and should be, pushed.

Being part of does not mean being sufficient.

Re: ITER: World's largest nuclear fusion project begins assembly

#62

Post by jjoonathan » Tue, Jul 28, 2020, 9:28 PM UTC

andrepd wrote: post #39

usui wrote: post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

I'm also a fusion power fanboy but >nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is a…

Hydro is actually pretty bad in terms of big safety incidents (Banqiao: 171000 dead, Machchu: 5000 dead, South Fork: 2208 dead) and solar/wind have trouble beating nuclear on metrics like death/watt because you need lots of infrastructure per watt. Picture a few large cities with contractors running around every roof tending to solar panels and compare to a few experts at a single nuclear power plant. For the contractors-on-roofs, the slip & falls add up even though they'll never get an HBO mini-series.

Anyway, I tend to agree that going forward solar + storage is probably workable. The storage part isn't proven yet but I have faith we'll figure it out. There are lots of promising options under investigation and the proven fallbacks aren't that horrendously expensive, all things considered.

It's just a pity we stopped building nuclear 40 years ago because it was viable all the way back then. Heck, we got to 20% nuclear! Compare to 2% solar today. If we had merely continued building nuclear at the same pace instead of stopping in the 1980s our grid would be 100% low-CO2 today instead of maybe 30 years from now if we hurry. But that didn't happen. We made the super-mature and responsible decision to fill our atmosphere with CO2 instead and now we get to live with that decision. So it goes.

Re: ITER: World's largest nuclear fusion project begins assembly

#63

Post by xixixao » Tue, Jul 28, 2020, 9:29 PM UTC

nharada wrote: post #20

usui wrote: post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

There's a good talk here about why ITER is so large: https://www.youtube.com/watch?v=L0KuAx1COEk The idea is essentially that to get the parameters needed to make net energy with tokamaks, you need either very strong magnets or a large device. At the time of ITER's design, they used the strongest magnets they could find and then made the thing big enough to get the energy gain they wanted. The speaker of this talk ar…

Also check out this UK company which is instead going down the path of using stronger magnets: https://www.youtube.com/watch?v=hWYnbYsp3i8

Re: ITER: World's largest nuclear fusion project begins assembly

#64

Post by elil17 » Tue, Jul 28, 2020, 9:30 PM UTC

kibwen wrote: post #52

thechao wrote: post #22

Earlier quoted context omitted.

Net-positive was achieved in 2013. As far as I can remember, ITER is a test-bed for economical and scalable nuclear fusion. Also, the corporate world (at least here in Texas, of all places) is perfectly capable of rolling out state-scale renewable power (wind).

> Net-positive was achieved in 2013. Do you have a source for this? I was also under the impression that fusion has never yet produced a net of energy.

If you define your efficiency metric in a clever way, anything is possible: https://io9.gizmodo.com/breakthrough-the-worlds-first-net-po...

Re: ITER: World's largest nuclear fusion project begins assembly

#65

Post by RandallBrown » Tue, Jul 28, 2020, 9:30 PM UTC

bawolff wrote: post #40

vosper wrote: post #29

Earlier quoted context omitted.

> nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone I assume by "energy crisis" you mean "how do we continue to generate energy while drastically decreasing climate effects"? Because if we're not worried about climate there's no looming energy crisis. There's plenty of oil, gas, and coal out there still. And…

> There's plenty of oil, gas, and coal out there still. I was under the impression we only had ~100 years worth of oil left, just that its not talked about because climate is more pressing and normal ecconomic pressures will fix the problem if we run out of supply. Is that wrong?

I think typically those predictions mean there's ~100 years of oil that's extractable with current prices and technologies, not that there won't be any oil left at all in 100 years.

Re: ITER: World's largest nuclear fusion project begins assembly

#66

Post by itsangaris » Tue, Jul 28, 2020, 9:30 PM UTC

andrepd wrote: post #39

usui wrote: post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

I'm also a fusion power fanboy but >nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is a…

>This is just not true

A lot of smart people would beg to differ.

Re: ITER: World's largest nuclear fusion project begins assembly

#67

Post by mjfl » Tue, Jul 28, 2020, 9:31 PM UTC

usui wrote: post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

With tokamaks, there is a concept of confinement time. It turns out that plasma is not stable in a standard donut configuration and it likes to twist and break the continuous column, sending all the plasma shooting at the walls. The confinement time is how long it takes for this to happen. After the many plasma experiments over the decades, scientists have a really good idea of how the confinement time scales with magnetic field strength and volume of the plasma. It turns out that you want a big machine. With the JET tokamak they were really close. Iter is designed to have the confinement time well within the requirements for net positive energy, with like a 10-fold margin of safety. IMO it should work, but it is taking an unacceptably long time to construct.

Re: ITER: World's largest nuclear fusion project begins assembly

#68

Post by throwaway0a5e » Tue, Jul 28, 2020, 9:31 PM UTC

usui wrote: post #21

gautamcgoel wrote: post #2

I think fusion is cool, but I also think it distracts from more important and promising approaches to clean power. No one has ever demonstrated a self-sustaining, net positive fusion reaction. It will probably take >30 years to make this technology cheap , safe and reliable and another >20 years to deploy it at scale. We don't have 50 years to wait on clean energy, we need it today. We should be focusing our attentio…

I do not think solar is going to work. As you say, it might take up to 50 years to crack the case on nuclear fusion. I argue that it might take up to 50 years for governments and companies around the world to even begin cooperating in a fashion such that they make a dent in carbon-based energy sources at the global scale using solar. The reason why solar is not going to work mostly is because there is no legitimate m…

Even if we deploy batteries, wind and solar in an amount needed to mitigate a climate change crisis, the amount of mining and industrial activity that would take would greatly poison our planet in other ways. In terms of "other stuff you need to do" per MW none of these come close to touching fission. Fusion, being much cleaner than fission would be a holy grail of clean cheap energy.

I hope it only takes 50yr to figure out and scale up fusion, that would be great.

Re: ITER: World's largest nuclear fusion project begins assembly

#69

Post by Corazoor » Tue, Jul 28, 2020, 9:34 PM UTC

StanAngeloff wrote: post #6

Some years ago, likely around 2010, I had the priviledge to visit Culham Centre for Fusion Energy (it was called UKAEA Culham back then). During my visit, we were shown around various experiments and after a long evening, we had the opportunity to attend a Q&A with the staff. The question everyone wanted to know the answer to was When will it be ready? The scientists and everyone else involved honestly thought 10 yea…

Well, they were not exactly wrong. Humanity as a collective would have been able to push the technology to a usable level in that timeframe, the knowledge for that was certainly there. But it would have required spending quite a lot more money on it. The incentives for that were simply not there, and that remains still true today.

With the current level of investment and committment, it's more like 40-50 years for the first real generator, and another 10-20 until the first commercial one.

Re: ITER: World's largest nuclear fusion project begins assembly

#70

Post by throwaway0a5e » Tue, Jul 28, 2020, 9:34 PM UTC

throwaway744678 wrote: post #32

The_rationalist wrote: post #14

Earlier quoted context omitted.

Maintain a fusion pulse for up to 8 minutes What does this mean?

My understating of the issue is that one need to keep the plasma is the adequate state for 1. the reaction to occur (i reckon we can do that for a fraction of a microsecond or something) 2. make it self-sustaining (we're not here yet) 3. Obviously without producing an H-bomb. Neighbours might get unhappy.

> 3. Obviously without producing an H-bomb. Neighbours might get unhappy.

If you do it wrong enough the neighbors won't even know.