5 ms·

300 MJ is about 83 KWh. In the UK is 1 KWh is £0.34 So, this costs £28 in electricity to run this experiment. The experiment is a momentary thing. Clearly t

300 MJ is about 83 KWh. In the UK is 1 KWh is £0.34 So, this costs £28 in electricity to run this experiment. The experiment is a momentary thing. Clearly there is now some work to, but now this is becoming an engineering problem of how to extend, sustain, and scale this process.

deleted 4y ago
[deleted]
moloch-hai 4y ago
Plus $10M for the target bead.
- philipkglass 4y ago
  Where did you see this estimate for hohlraum cost? The NIF fired 368 shots in 2021: https://lasers.llnl.gov/for-users/nif-target-shot-metrics https://lasers.llnl.gov/for-users/nif-target-shot-metrics At $10 million per target that would cost $3.7 billion. The annual LLNL budget (which includes NIF) is only $2.8 billion: https://www.llnl.gov/doing-business/economic-impact https://www.llnl.gov/doing-business/economic-impact As of 2004, the targets were reported to cost $2500 each: https://www.osti.gov/servlets/purl/828518 https://www.osti.gov/servlets/purl/828518
  - moloch-hai 4y ago
    Got it from a comment on here. The 2004 targets didn't work. Neither did the 368 shots in 2021. Maybe ones that work cost more? Even $2500 for 1 kWh is rather steep.
tuatoru 4y ago
To have a hope of supplying grid power, they need to scale up the energy gain by four orders of magnitude and reactor run time by 12 orders of magnitude. Those are just two of the engineering problems. It'll be a while, and I doubt it will ever compete with solar, wind, and storage.
- eru 4y ago
  > [...], and I doubt it will ever compete with solar, wind, and storage. Maybe not on earth, but there are applications in deep space.
  - danw1979 4y ago
    This is exactly why we need to keep plugging away at fusion - one day we’ll need it in space. It doesn’t have to be cheap, it just has to work.
    - eru 4y ago
      Of course, whether that's a good investment of resources right now is another question. Even if we had no other goal than becoming an intergalactic species as soon as possible, we might still benefit from working on other things first.
      - bratbag 4y ago
        You are operating under the rather naive assumption that the people and resources used in fusion research are fungible with the people and resources used in other things. When you have a bunch of people who know how to build nuclear bombs sitting around with nothing to do, you damn well keep them busy before another country finds them a job.
        eru 4y ago
        For further discussion, we'd need to be careful whose perspective we are taking and what timescales we are talking about. You seem to be taking the perspective of individual countries? And not eg humanity. And timescales of perhaps decades? On longer timescales: people don't get born knowing how to build nuclear bombs. They are trained up.
  - rbanffy 4y ago
    > Maybe not on earth, but there are applications in deep space. Depends on how long the interstellar craft is supposed to travel. If it's under 100 years, fission should be able to do the trick of keeping the craft warm and the lights on for the sealed ecosystem to function during the decades of coasting between stars. Fusion rockets would be more convenient than fission ones because you can store the hydrogen you need in the form of water and water also acts as a great radiation shield while in deep space. Then, to brake, you use your radiation shield as reaction mass for fission or fusion rockets. If we are talking about much more than that, fusion is probably a better answer as fission fuel will half-life itself into paperweights over a grand transgalactic tour.
deleted 4y ago
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doctorwho42 4y ago
Having worked in the field for 6 years, the estimated cost per shot at NIF is roughly $1MM. The estimated cost for a day of shots at OMEGA is $250k-$300k. The cost per target varies a lot due to the precise manufacturing tolerances and the methods to get them. For example, the sphere with the fuel in it is made by dropping liquid glass from a drop tower. And then metrology is done on hundreds and hundreds of glass spheres. So though the electricity might cost that, we are talking about a building in which just the lasers and their optical paths take up 3 foot ball fields of advanced warehouse space. And the target chamber is at ultra high vacuum, which is 10 meters in diameter. There are also countless diagnostics, computers, and other electronics, the lights for all the facility, and the number of people required to run it so this delicate experiment goes off without a hitch. Honestly, it's almost not worth talking about as a power source anytime soon. Even if Q > 2 on NIF there are countless engineering problems that would have to be overcome (and haven't really been thought too hard on in the ICF field) to get a power reactor out of this tech. My two cents, look towards MIT and CFS for news on their SPARC tokamak and plans for ARC tokamak. Based on some data I have seen, SPARC should hit Q>1 pretty easily. With some estimates of reaching Q> 3 to 9. And before you scoff at it, this reactor design is using magnetic tech that has proven it can withstand and produce a 20T magnetic field! In MCF, field strength and heating are the two key metrics. To put this into perspective, the massive tokamak being built in Europe has a MAX possible field strength of 13T, assuming it's run to the edge of it's theoretical design limitations. The SPARC one hasn't even been run to it's design limitations, most likely due to the mechanical stresses a 20T field produces in a 3-4 meter D coil.

deleted 4y ago

[deleted]

moloch-hai 4y ago

Plus $10M for the target bead.

philipkglass 4y ago
Where did you see this estimate for hohlraum cost? The NIF fired 368 shots in 2021: https://lasers.llnl.gov/for-users/nif-target-shot-metrics https://lasers.llnl.gov/for-users/nif-target-shot-metrics At $10 million per target that would cost $3.7 billion. The annual LLNL budget (which includes NIF) is only $2.8 billion: https://www.llnl.gov/doing-business/economic-impact https://www.llnl.gov/doing-business/economic-impact As of 2004, the targets were reported to cost $2500 each: https://www.osti.gov/servlets/purl/828518 https://www.osti.gov/servlets/purl/828518
- moloch-hai 4y ago
  Got it from a comment on here. The 2004 targets didn't work. Neither did the 368 shots in 2021. Maybe ones that work cost more? Even $2500 for 1 kWh is rather steep.

tuatoru 4y ago

To have a hope of supplying grid power, they need to scale up the energy gain by four orders of magnitude and reactor run time by 12 orders of magnitude. Those are just two of the engineering problems. It'll be a while, and I doubt it will ever compete with solar, wind, and storage.

eru 4y ago
> [...], and I doubt it will ever compete with solar, wind, and storage. Maybe not on earth, but there are applications in deep space.
- danw1979 4y ago
  This is exactly why we need to keep plugging away at fusion - one day we’ll need it in space. It doesn’t have to be cheap, it just has to work.
  - eru 4y ago
    Of course, whether that's a good investment of resources right now is another question. Even if we had no other goal than becoming an intergalactic species as soon as possible, we might still benefit from working on other things first.
    - bratbag 4y ago
      You are operating under the rather naive assumption that the people and resources used in fusion research are fungible with the people and resources used in other things. When you have a bunch of people who know how to build nuclear bombs sitting around with nothing to do, you damn well keep them busy before another country finds them a job.
      - eru 4y ago
        For further discussion, we'd need to be careful whose perspective we are taking and what timescales we are talking about. You seem to be taking the perspective of individual countries? And not eg humanity. And timescales of perhaps decades? On longer timescales: people don't get born knowing how to build nuclear bombs. They are trained up.
- rbanffy 4y ago
  > Maybe not on earth, but there are applications in deep space. Depends on how long the interstellar craft is supposed to travel. If it's under 100 years, fission should be able to do the trick of keeping the craft warm and the lights on for the sealed ecosystem to function during the decades of coasting between stars. Fusion rockets would be more convenient than fission ones because you can store the hydrogen you need in the form of water and water also acts as a great radiation shield while in deep space. Then, to brake, you use your radiation shield as reaction mass for fission or fusion rockets. If we are talking about much more than that, fusion is probably a better answer as fission fuel will half-life itself into paperweights over a grand transgalactic tour.

deleted 4y ago

[deleted]

doctorwho42 4y ago

Having worked in the field for 6 years, the estimated cost per shot at NIF is roughly $1MM. The estimated cost for a day of shots at OMEGA is $250k-$300k. The cost per target varies a lot due to the precise manufacturing tolerances and the methods to get them. For example, the sphere with the fuel in it is made by dropping liquid glass from a drop tower. And then metrology is done on hundreds and hundreds of glass spheres. So though the electricity might cost that, we are talking about a building in which just the lasers and their optical paths take up 3 foot ball fields of advanced warehouse space. And the target chamber is at ultra high vacuum, which is 10 meters in diameter. There are also countless diagnostics, computers, and other electronics, the lights for all the facility, and the number of people required to run it so this delicate experiment goes off without a hitch. Honestly, it's almost not worth talking about as a power source anytime soon. Even if Q > 2 on NIF there are countless engineering problems that would have to be overcome (and haven't really been thought too hard on in the ICF field) to get a power reactor out of this tech. My two cents, look towards MIT and CFS for news on their SPARC tokamak and plans for ARC tokamak. Based on some data I have seen, SPARC should hit Q>1 pretty easily. With some estimates of reaching Q> 3 to 9. And before you scoff at it, this reactor design is using magnetic tech that has proven it can withstand and produce a 20T magnetic field! In MCF, field strength and heating are the two key metrics. To put this into perspective, the massive tokamak being built in Europe has a MAX possible field strength of 13T, assuming it's run to the edge of it's theoretical design limitations. The SPARC one hasn't even been run to it's design limitations, most likely due to the mechanical stresses a 20T field produces in a 3-4 meter D coil.