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

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

#41

Post by svara » Tue, Jul 28, 2020, 9:10 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…

It's a bit odd to me that you seem to deem fusion power realistic, while discounting other ways of generating and storing power that are basically available already.

Power from renewables can be stored for the long term as hydrogen. That's well understood technology, scaling up is an engineering problem. When the sun shines and the wind blows, solar and onshore wind are the cheapest ways to make electricity, so there's a huge economic incentive to solving the storage issue.

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

#42

Post by f6v » Tue, Jul 28, 2020, 9:12 PM UTC

vosper wrote: post #29

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…

> 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…

It seems to me that it’s a question of long term energy needs, i.e. when civilization goes to the next level and wants to send laser-propelled light-sail equipped probes to other planets with 10% speed of light.

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

#43

Post by xupybd » Tue, Jul 28, 2020, 9:12 PM UTC

vosper wrote: post #29

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…

> 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…

As I understand it renewables and batteries have their own environmental impacts that can't be ignored. When comparing nuclear with renewables the impacts start to show nuclear as at least a good contender as the future power source. But large scale fusion might drastically lower energy costs. That could enable things like carbon capture.

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

#44

Post by Certhas » Tue, Jul 28, 2020, 9:12 PM UTC

vosper wrote: post #29

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…

> 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…

Methanization is currently expected to be the critical storage component for CO2 neutral energy systems. A major driver of storage need in many places is not renewable fluctuations but seasonal fluctuations: You need more heating in winter/AC in summer. So make Methane and store the gas. Technologically this is all solved.

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

#45

Post by ovi256 » Tue, Jul 28, 2020, 9:13 PM UTC

toohotatopic wrote: post #27

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…

>looming energy crisis Where do you see the crisis? Unless you want to provide everybody with an abundance of energy, people need food and shelter, some electricity for electronics and some transportation once in a while. Of course, any amount of energy can be burned for simulations and bitcoins but that's simply limited by supply. There will be a crisis when bitcoins and simulations are more valuable than human live…

>people need food and shelter, some electricity for electronics and some transportation

Modern shelter, food and transportation means a lot of energy.

Modern shelter means operating energy for heating or air conditioning, plus embedded energy used to create its components. If the shelter is green, or "energy efficient", it means it is operating energy efficient, but it contains a huge amount of embedded energy in the insulation and heat exchange components.

Air conditioning doesn't necessarily have a worse bottom line, energy wise, than just heating. It's all about the time * temperature difference envelope. Air conditioning usually has a much lower temperature difference between the outside and the inside. If it's 40 C (as hot as it gets in places where masses of people live) outside, air conditioning has to drop by 15 C to get the inside to 25. If it's freezing (0 C) outside, heating has to heat by 25 C.

Double that for a modern workplace - office, warehouse or manufacturing, they all consume a lot of energy to keep the workers comfortable.

Modern high-speed transportation means a lot of energy too. We move crash-resistant 1500 kg structures at highway speeds around daily.

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

#46

Post by tomtomtom777 » Tue, Jul 28, 2020, 9:13 PM UTC

toohotatopic wrote: post #27

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…

>looming energy crisis Where do you see the crisis? Unless you want to provide everybody with an abundance of energy, people need food and shelter, some electricity for electronics and some transportation once in a while. Of course, any amount of energy can be burned for simulations and bitcoins but that's simply limited by supply. There will be a crisis when bitcoins and simulations are more valuable than human live…

This is an odd jump you are making. Most energy isn't used just for food, shelter and some transportation, and certainly not for "bitcoin and simulations".

By far most energy is used to produce things (including the transportation requirements to do so). And as it turns out, the hunger for producing and buying new things is very hard to temper. This hunger is evident from the fact that the ways we are measuring "economic success" strongly correlates with the amount of things we produce, or even with the speed at which we are increasing the amount of things we produce.

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

#47

Post by cmdli » Tue, Jul 28, 2020, 9:15 PM UTC

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 would argue that we are already seriously building more and more solar and wind power, along with research into better battery storage. Even if we solve the current climate crisis with solar and wind, we may still be able to do even better with fusion in 50 years. Fusion would be very energy dense, requiring a lot less resources and land than solar or wind, and has the potential for even cheaper and less environmentally-destructive energy than current renewable resources.

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

#48

Post by petschge » Tue, Jul 28, 2020, 9:15 PM UTC

fabian2k wrote: post #38

nharada wrote: post #20

Earlier quoted context omitted.

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…

I wonder how much the possible magnet strength affects the design of a tokamak. There are very clear limits on the field strength you can achieve with classical superconductors, and I know e.g. in Nuclear Magnetic Resonance those limits had been almost hit maybe a decade ago or so. But very recently spectrometers based on new high-temperature superconductors have been delivered, so the technology seems to be far enou…

Yes that has a big impact. The quality of a tokamak (as meassured by the triple product density, temperature, and confinement time) goes up like B^3 (IF I remember correctly, I do plasma physics but not fusion stuff) and the fussion power goes up like B^4 or something like that. So larger magnetic fields help a lot. But back when ITER was designed we did not have such strong superconductors yet.

PS: Google found DOI 10.1088/0029-5515/56/6/066003 but I didn't read it carefully.

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

#49

Post by f6v » Tue, Jul 28, 2020, 9:15 PM UTC

throwaway744678 wrote: post #26

spacephysics wrote: post #15

Earlier quoted context omitted.

I agree we should look at multiple possible paths for renewable energy, but to say that they shouldn’t work on this, is a bit far fetched. This assumes the researchers working on fusion can work on the other renewable energies, when that’s typically not the case with highly specialized fields. Further, estimating the time it takes for advancement with the described time magnitude is a frivolous pursuit, if you put an…

Your argument is sound, but the issue is also budget allocation: financial resources are not infinite, and we must choose how to allocate them.

There’s so much things to divert budget from to fuel energy research. Completely unrealistic, but think luxury cars, football player’s salaries, just to name a few.

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

#50

Post by nikitaga » Tue, Jul 28, 2020, 9:17 PM UTC

vosper wrote: post #29

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…

> 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…

Which fossil fuels are "less bad" for the climate? They're all very bad.

Obviously old coal powerplants are the worst, but there's more evidence every year that the allegedly "clean" natural gas is nowhere as clean as advertised once you account for fugitive methane emissions that in practice are largely untracked. And flooding the market with cheap fossil fuel like methane as a "transition fuel" – another marketing gimmick – will only delay the transition to renewables for obvious economic reasons.

I'm not optimistic about big shots like fusion, but small modular nuclear reactors for example could be operating relatively soon if only we had the desire to go in that direction.