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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

#961

Post by qbrass »

eklitzke wrote: post #262
spullara wrote: post #165

Earlier quoted context omitted.

If you look at the mass before of their fuel, 1 deuterium atom + 1 tritium atom: 2.01410177811 u + 3.01604928 u = 5.03015105811 u vs the mass of the fusion products of 1 helium atom and 1 neutron: 4.002602 u + 1.008 u = 5.010602 u You'll notice that even though we started with 5 neutrons and 2 protons and ended up with the same number there was some additional binding energy that is unaccounted for in the new configu…

Tangentially related, but I think this is an interesting fact, all the atoms in our universe/galaxy/solar system with a mass up to that of iron are formed in the core of stars in stellar fusion. Hydrogen fuses into helium, and as a star nears the end of its lifetime you get heavier elements like lithium, carbon, and so on. Under normal stellar fusion no elements heavier than iron will be produced, and iron is only el…

Heavier elements supposedly come from two neutron stars colliding because even a single star exploding isn't enough energy.

So think about two stars killing each other to make your jewelry.

Re: US Department of Energy: Fusion Ignition Achieved

#962

Post by samvher »

eru wrote: post #793
floxy wrote: post #686

Earlier quoted context omitted.

I guess we should take this as a lesson in communications. The "breakeven" thing is a red-herring that should have been have been left out of the message, or at least only mentioned as a footnote. The critical ELI5 message that should have been presented is that they used a laser to create some tiny amount of fusion. But we have been able to do that for a while now. The important thing is that they were then able to…

> [...], or the ginormous fusion of the sun. The sun actually has very little fusion per cubic metre or per kg. Per volume the core of the sun produces only a quarter of the heat of the human body (and per kg it's even less, owing to high density). That's why our fusion reactors can't just mimic stars, they have to far surpass them to be useful to us.

Can you say more about the ways in which fusion reactors need to surpass stars, and why people believe it's feasible that we can sufficiently get to that point?

(Also - thanks for sharing one of the most interesting comments I've read on the internet in quite a while.)

Re: US Department of Energy: Fusion Ignition Achieved

#963

Post by DesiLurker »

lossolo wrote: post #744
DesiLurker wrote: post #355

Earlier quoted context omitted.

Imagine if we've spent 10% of the current military budget ($600B+) on renewables & fusion. We wouldn't have to fight those wars for resources.

> We wouldn't have to fight those wars for resources. You mean wars for oil? Fusion would not solve that, that wars were not about energy per se but about control and domination, keeping USD as world reserve currency and US as world hegemon. Look at Taiwan and chips situation, no oil there, there will be always some "oil" out there that you will want to control instead of giving that control to your rivals. It's game…

okay but oil is a fundamental input into everything hence a much bigger threat than say TSMC's nextgen fab. everybody understands that with some effort those outputs of a strong economy can be recreated but not inputs. Arguably lithium or water may become that but we are currently far from it. Sure there will always be something we'd want to control but we can go in more calm, clearheaded way towards it rather than just use force because we have the biggest stick.

people love to invoke game theory but fail to explain why only we spend more than next 10 countries military budget combined. plus its quite unclear what we get out of it because of all the secrecy & likely its mostly inflated costs and kickbacks. The wars in Iraq/Afghanistan themselves have cost close to 3T over time & thats outside of annual budgets. Personally I'd have preferred to take medicare for all for that amount of money.

Re: US Department of Energy: Fusion Ignition Achieved

#964

Post by moloch-hai »

salawat wrote: post #828
moloch-hai wrote: post #570

Earlier quoted context omitted.

Each dollar diverted to chase nuke wills-o'-th'-wisp brings climate catastrophe nearer. Money is fungible. Dropping $billions on this means not dropping those $billions on something that works already, works fantastically well, and would work even better with more money. We already know how to prevent (more) climate catastrophe. We just need to do more of it.

So drop it on fission. There. Settled.

Fission means, in practice, paying enough for coal generation, over the decade, to have built enough solar to displace the nuke; and paying many times that, on top, to build the nuke.

So, no. Each dollar diverted from building out solar to mining coal or fooling with nukes brings existential catastrophe nearer.

Re: US Department of Energy: Fusion Ignition Achieved

#965

Post by smolder »

Balgair wrote: post #574
mustacheemperor wrote: post #2

I don't know about everyone else, but I'm taking this particular moment just to swell with pride and excitement for this achievement by science and forget about the details of how much more needs to be done to create the first power plant. I'm remembering when I first learned about fusion energy development, how distant and unfeasible it seemed, and regardless of how long the road ahead still is it's incredible how f…

I agree. This is a Big deal. Like, first-lightbulb big, or polio-vaccine big. My kids are likely to spend the majority of their lives living a world where energy is clean, cheap, and available to everyone. Climate change is something that is not only going to be stopped, but can be reversed for them. Energy grids can be made to be smaller and mutually supporting, lessening the impacts of disasters. Oil dependency and…

Not that I enjoy being a downer, but I think we're still quite a ways off from a trajectory towards Star Trek society. Clean energy production is absolutely key, with pollution and climate change being big obstacles to a prosperous future, but clean energy doesn't solve all air and water pollution. It won't necessarily scale economically. It also doesn't temper any megalomaniac's pride, to stop them from creating conflict as they try to subjugate everyone else. We live in a very divided, hierarchical world with a fragile order, subject to the whims of people with godlike power over the masses.

One of the most fantastical aspects of Star Trek was the societal evolution into one without interpersonal conflict, the idea being that without scarcity there's no good reason for conflict... I'm just not sure how well that would hold up, knowing people. I don't think all desire for status and power stems from scarcity of resources, and people will continue to lie and do harm to each other as long as they desire power over others.

> My kids are likely to spend the majority of their lives living a world where energy is clean, cheap, and available to everyone.

Being available to everyone does depend on who "everyone" is. If people use the energy to grow food (and more people) until we run into some other population-limiter, we'll always have too many people. Part of achieving sustainability is ending runaway growth. Maybe you can ask people nicely enough to stop reproducing, maybe education will do it, maybe nothing short of force will. Yet our economics were built around continual growth. So, that's all a big problem to solve, still.

Re: US Department of Energy: Fusion Ignition Achieved

#966

Post by lossolo »

DesiLurker wrote: post #963
lossolo wrote: post #744

Earlier quoted context omitted.

> We wouldn't have to fight those wars for resources. You mean wars for oil? Fusion would not solve that, that wars were not about energy per se but about control and domination, keeping USD as world reserve currency and US as world hegemon. Look at Taiwan and chips situation, no oil there, there will be always some "oil" out there that you will want to control instead of giving that control to your rivals. It's game…

okay but oil is a fundamental input into everything hence a much bigger threat than say TSMC's nextgen fab. everybody understands that with some effort those outputs of a strong economy can be recreated but not inputs. Arguably lithium or water may become that but we are currently far from it. Sure there will always be something we'd want to control but we can go in more calm, clearheaded way towards it rather than j…

> Sure there will always be something we'd want to control but we can go in more calm, clearheaded way towards it rather than just use force because we have the biggest stick.

Unfortunately no, you can't go more calm because projection of force is what keeps status quo and your rivals in place, not liberal values or clearheaded minds. There is no world police, the one with the biggest stick makes the rules. US is not the first hegemon in history of the world, we had Roman Empire, we had Dutch Empire etc, all of the world hegemons were major military powers. There is always some challenger waiting in the shadows to take over your position, you can't just sit and be calm because you will lose what you have, I assure you that others will not just sit calm but claim what's yours if they see sign of weakness, history proves that again and again.

> but fail to explain why only we spend more than next 10 countries military budget combined

Well it's easy to explain, US have it in its doctrine that it needs to have military strong enough to fight 2 wars at a time so it needs to spend more than at least a few countries behind it but a lot of this budget is probably not spent well. The problem here is that when you stop being world hegemon with the biggest stick, your currency stops being world reserve currency which means you can't finance your debt the same way as before, which has drastic consequences to your budget and it would be really fatal for US. Sometimes you just can't stop the music even when you don't like the melody because silence will hurt you.

> plus its quite unclear what we get out of it because of all the secrecy & likely its mostly inflated costs and kickbacks.

Agreed that's inefficient, you probably could achieve the same with lower costs but how much lower I don't know if anyone knows.

Re: US Department of Energy: Fusion Ignition Achieved

#967

Post by grecy »

anon291 wrote: post #959
grecy wrote: post #823

Earlier quoted context omitted.

I’ve driven many many tens of thousands of miles through landscapes with intense sun and extremely close to zero vegetation or life. Damaging that has got to be a lot better for the planet than coal or nuclear.

Even the great deserts of the southwest have life. In fact, I challenge you to drive through these tens of thousands of miles of landscapes in the hour or two after a rainstorm and tell me they're dead. You're missing out if you've not seen the desert in bloom. I grew up by the desert, and I don't know why people think it's dead. There are some extremely fragile ecosystems there.

> great deserts of the southwest

Sounds like you're talking about a single country?

I'm talking about when I've driven through the Sahara (West and East side), Namib, Simpson, Great Sandy, Gibson, etc. etc.

There is a HUGE amount of land on earth for things like solar and wind.

Re: US Department of Energy: Fusion Ignition Achieved

#968

Post by m55au »

davrosthedalek wrote: post #402
dsfyu404ed wrote: post #321

Earlier quoted context omitted.

There's a fundamental tradeoff between technical precision and explaining things in a way that's relatable to simpler stuff. Deal. With. It.

Not if the original description is exactly the opposite of what happens. You get energy out by making stronger bonds.

Stronger bonds by definition are lower energy bonds. So you get energy out by making the total bond energy go lower or "releasing it".

Re: US Department of Energy: Fusion Ignition Achieved

#969

Post by panick21_ »

devmor wrote: post #894
panick21_ wrote: post #610

Earlier quoted context omitted.

Yeah but are you beating fission, something like: https://www.moltexflex.com/flex-reactor/ A small fission reactor can do almost everything a fusion reactor can. Fusion fuel is higher density, but fission density is already not an issue. Fusion still needs to heat water, that's where much of the cost comes from.

A small fission reactor is also incredibly dangerous and will always require exotic material. A fusion reactor does not pose environmental risk and could eventually run on highly available basic elements for everything after the initial "startup" once the technology progresses.

What exotic materials? Molten salts and steel is most of it. These reactors have essentially 0% chance to have airborn escape of radiation.

An fusion reactors don't actually run on basic elements. The require a fuel that is specially breed. And when they operate they have radioactive materials that can go airborn.

Re: US Department of Energy: Fusion Ignition Achieved

#970

Post by moloch-hai »

rnhmjoj wrote: post #918
elihu wrote: post #813

Earlier quoted context omitted.

> The fusion startups are spending down investors' money with zero possibility of payback (Helion conceivably excepted), because if they did get Q>1, they have no workable way to harness it. ITER will not even try to produce one watt-second of electricity. Its follow-on demo reactor won't start building until 2050, if not further delayed. You seem to be awfully certain of that. I'm not an expert in this area, but my…

> There's no plan to hook ITER up to a thermal plant because it's a research reactor not a power plant Interestingly, that's not really true: IIRC the japanese team working on the WCCB breeder module (that uses supercritical water as coolant) plans on connecting the water loop to a small turbine. If they succeed it would be the first ever electrical power produced from fusion.

Ability of steam to drive a turbine doesn't seem to be in dispute.

Making tea would be better theater, if they need that, and cheaper: "the first tea ever brewed by over-unity fusing neutrons".

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