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US Department of Energy: Fusion Ignition Achieved

energy.gov

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Re: US Department of Energy: Fusion Ignition Achieved

#941

Post by User23 »

_cs2017_ wrote: post #836
User23 wrote: post #807

Earlier quoted context omitted.

The USA no longer has the technical capability to manufacture the necessary parts to maintain the current stockpile. The whole strategic arms reduction treaty regime is basically a fig leaf to cover for the fact that we have to cannibalize some legacy weapons to maintain the rest. If nothing changes the USA probably won't have an effective arsenal within a century. Given the likely state of the USA by that time, that…

Interesting, but: 1. How does this research help address this problem? 2. What are the sources for your opinion?

> 1. How does this research help address this problem?

I see it the other way around, this problem makes me doubt that this research will ever actually lead anywhere, supposing it's even as good a result as it first appears.

> 2. What are the sources for your opinion?

It's a fact. And my source is dead tree media. I don't recall all the details, but there are some very finicky parts that go into a state of the art warhead and we have lost the capability to manufacture them. Is this really so surprising? We can't even build new F-22s anymore!

Re: US Department of Energy: Fusion Ignition Achieved

#942

Post by HPsquared »

ramijames wrote: post #855
bboygravity wrote: post #817

Earlier quoted context omitted.

No you can't because solar isn't a continious source and fusion is. No amount of investment into solar power can make the sun magically shine 24 hours a day.

I mean, you could literally build a ring of solar power collectors and microwave transmitters in orbit. It would always have 50% coverage.

Or just have a bunch of power lines running east-west.

Re: US Department of Energy: Fusion Ignition Achieved

#943

Post by User23 »

scoopertrooper wrote: post #884
kubanczyk wrote: post #879

Earlier quoted context omitted.

> > USA probably won't have an effective arsenal within a century. > If other countries joined, it would be a great outcome. Why the optimism? Without MAD, it's nearly certain that we'd have a world war at some point in time. Sooner or later, it will surely happen. If you think it won't happen, or won't cost millions of lives, or won't employ re-developed nukes eventually, please tell me why you think so. (No sarcasm…

I don’t think MAD is all that effective. At this moment in time we’re seeing: * Several concurrent arms races in the Middle East, Asia, and Europe * A high intensity conflict in Ukraine * China threatening a land invasion into Taiwan MAD might be preventing a country like Poland from jumping into the Ukraine conflict, but more likely it’s because of its involvement in NATO. I think collective security organisations a…

> Several concurrent arms races in the Middle East, Asia, and Europe

Which is to say, possible future proxy wars between the great powers where MAD will supposedly restrict conflict intensity. See below.

> A high intensity conflict in Ukraine

What's going on in Ukraine is a bog standard cold war style proxy war. The NATO plan is basically to turn it into another Afghanistan for the Russians. It's the exact thing that MAD is meant to keep from spilling over into a world war between the principals.

> China threatening a land invasion into Taiwan

This is more interesting. US conventional forces almost certainly have no hope of beating China that close to home. Therefore, any effective US response would require nuking China and China is presumably deterring that with their nukes. There is an argument to be made here that a non-nuclear Chinese military would be in Taiwan's best interests. However, I see no scenario where either a nuclear or non-nuclear China and a non-nuclear USA is in Taiwan's best interests. So while the MAD case isn't the best case for Taiwan here, it's also not the worst.

Re: US Department of Energy: Fusion Ignition Achieved

#944

Post by kahrl »

gabesullice wrote: post #782

After the Wright brother's first demonstration of powered flight, I like to imagine all the pessimists in this thread would have said that commercial air transport would never be viable because wood and fabric don't have the material properties to carry a ton of steel.

This is a false equivalence.

Re: US Department of Energy: Fusion Ignition Achieved

#945

Post by RobinL »

iamgopal wrote: post #764
opportune wrote: post #584

Earlier quoted context omitted.

100% agree. We should be dumping as much as we can in getting fusion up and running ASAP. It could be a silver bullet to stop climate change alone, and by driving energy costs lower, enable huge innovations in AI/automation and increasing material wealth. $1T to move fusion forward just 5 years from eg 2040 to 2035 could alone have a huge ROI in terms of climate mitigation and decarbonization

How easy is to write $1T, but with that you can basically install enough solar cell to power all of USA energy need.

Here's some rough numbers, hopefully i haven't made any mistakes:

Total US energy generation 2021: 4 trillion kwh

Average power generation: 457Gw

Cost of Topaz solar farm: $2.5bn Potential output: 550 Mw Cost per Mw $4.5m

Spend a trillion on similar capacity, you get 220Gw potential output.

But that's assuming you get 550Mw average. In fact, it produces about 1282Gwh output a year, so average is more like 145Mw.

So at a rough estimate, you need more like 10 trillion to meet US electricity demand. And that assumes you have unlimited battery storage for free.

And of course electricity is a small minority of total energy use.

Incidentally, I think it's amazing you get to about 10% of total electricity needs with only $1tr, i.e. around 4% of US national output.

https://en.wikipedia.org/wiki/Topaz_Solar_Farm https://www.eia.gov/energyexplained/electricity/electricity-...

```python trillion_dollars = 1e12

mw = 550

cost_farm = 2.5e9

cost_dollar_per_mw = cost_farm/mw

num_mw = trillion_dollars/cost_dollar_per_mw

num_gw = num_mw/1000

num_gw

kwh = 4e12

mw = kw/1000

gw = mw/1000

gw ```

Re: US Department of Energy: Fusion Ignition Achieved

#946

Post by jboy55 »

_cs2017_ wrote: post #835
jacquesm wrote: post #774

Earlier quoted context omitted.

Given the limitations on nuclear research for weapons purposes any information that can be gleaned from these experiments that is 'dual use' is more than welcome with the parties that are currently stymied by various arms control agreements. This is also why you will see a lot of supercomputer capacity near such research, it allows simulation of experiments with high fidelity rather than the experiments themselves. T…

Presumably these computer models are mostly useful for creating new designs (since the old designs were proven by real tests). Would such new designs be convincing enough to the adversary to fulfill its role as a strategic deterrence? When (in XX years?) almost all US nukes are only simulated on computers and not actually tested, the Russians may start wondering if the US aresnal actually works, no? That would be a h…

Or the US finds that after x many years bombs degrade in unexpected ways, and that while we were able to figure this out and fix it. Then we speculate that the Russians probably haven't fixed theirs in the same way and their bombs aren't good anymore. Which means the risk of a nuclear war just jumps up, since MAD is compromised.

Re: US Department of Energy: Fusion Ignition Achieved

#947

Post by jboy55 »

User23 wrote: post #941
_cs2017_ wrote: post #836

Earlier quoted context omitted.

Interesting, but: 1. How does this research help address this problem? 2. What are the sources for your opinion?

> 1. How does this research help address this problem? I see it the other way around, this problem makes me doubt that this research will ever actually lead anywhere, supposing it's even as good a result as it first appears. > 2. What are the sources for your opinion? It's a fact. And my source is dead tree media. I don't recall all the details, but there are some very finicky parts that go into a state of the art wa…

The most famous key component that was speculated or leaked, was that we lost the makeup and reason for the Styrofoam that holds the primary and surrounds the secondary.

This research successfully initiated fusion, using a capsule of hydrogen made of some material, surrounded by something, with an outer layer. This outer layer is turned into X-Rays by the laser, which then ablate the hydrogen capsule's casing casing the inwards pressure. You could speculate, that they just found the makeup for something that would replace the Styrofoam, or we just improved upon it.

Re: US Department of Energy: Fusion Ignition Achieved

#948

Post by hatsunearu »

bzbarsky wrote: post #932
epgui wrote: post #929

Earlier quoted context omitted.

The per-volume claim rings alarms in my head. If it produced a quarter of the heat of the human body per volume, its temperature would be lower as well (less than 37 degrees Celsius).[1] This is obviously not the case. [1] Obviously heat and temperature are not the same, I know that. But when something’s temperature is higher than another thing’s, then heat is exchanged along that gradient. Meaning if the sun produce…

Heat and temperature are indeed not the same. For both the sun and a human on earth there are two processes going on: 1. Heat production per unit volume. 2. Heat loss per unit surface area. The volume to surface area ratio for the sun is much larger than for the human, for a minor reason (the sun is a sphere) and a major reason (the sun's linear size is much bigger). So the equilibrium temperature of the sun in the s…

Yeah, this is a morbid analogy but if you got a bunch of people enclosed in a small area, the people in the middle will get so hot they will heatstroke, even if it's freezing outside. See the recent Korean crushing disaster.

Re: US Department of Energy: Fusion Ignition Achieved

#949

Post by r2_pilot »

Retric wrote: post #772
naikrovek wrote: post #760

Earlier quoted context omitted.

none of what anyone said is about a self-sustaining reaction. this is about more power leaving the reaction chamber than what entered it. that's all the announcement is about. this is NOT about how much energy it takes to ready the lasers. this is NOT about the electricity consumed by lighting, computers, cooling, or measurement or anything else-- none of that counts when you are measuring the efficiency of the react…

> none of what anyone said is about a self-sustaining reaction. Actual power plants are self sustaining as in they use the electricity they produce to operate, it’s mandatory though not sufficient for any commercial fusion power plant. So, this isn’t about a different way to “calculate reaction efficiency better than the physicists doing the work” he was directly quoting their numbers from the paper. It’s only a ques…

> Actual power plants are self sustaining Actual power plants are not necessarily self-sustaining and practically none of them can start if the grid power is not available. See: black start power plants and https://youtu.be/uOSnQM1Zu4w

Re: US Department of Energy: Fusion Ignition Achieved

#950

Post by blincoln »

kamaal wrote: post #850
ClumsyPilot wrote: post #505

Earlier quoted context omitted.

There are like 20 designs of various fusion reactors on the drawing board that need to be built and tested. Scientists also don't work for free. They arent mushrooms that grow by themselves

Beginner question, why is it hard(not possible) to calculate the gain without actually building a reactor? Surely if you have a non-satisfactory yield you shouldn't be building it. And that should be possible to estimate before we spend billions on it?

Simulations and estimations about processes in the physical world always leave room for surprises when one is doing things that haven't been done before.
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