291–300 of 1001 posts
I'm still a little unclear on the benefits that fusion offers compared to things like wind and solar. I understand that we need to develop better storage technologies for the energy produced by wind and solar, but that seems so much easier than the challenges currently facing fusion. Wind and solar just seem so far ahead of fusion already - they're pretty cheap and very widely deployed on a global scale. In compariso…
Here's your most exciting paragraph > LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE). Many advanced science and technology developments are still needed to achieve simple, affordable IFE to power homes and busines…
Imagine if Musk spend 44 Billion fusion
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Uh what US warfare have you been watching? Your analogy only works if it’s the like the 2000-200 Bulls (15-67).
> Uh what US warfare have you been watching? Russia is struggling with Ukraine and the NATO weaponry they've been gifted. 100 mile supply lines proved too much, and they failed entirely to achieve air superiority. There's zero reason to think they'd do better against the US more directly.
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This is a stupid question but I don't know anything about fusion: How is it possible for X energy to create X+Y energy in output? Doesn't that violate some fundamental law of physics?
You know how when you burn something you release the energy in the chemical bonds? Fusion and fission are like that but for atoms instead of molecules.
But, O2 molecules, with their double bond, don’t take much energy to break apart. If they do, and then pair up with say a bunch of Hydrogen and Carbon atoms that were nearby in some long chain or something, they form bonds that are stronger - that take more energy to break - and you end up with some leftover energy. Water and CO2 molecules are an even lower energy configuration.
but the extra energy you get wasn’t exactly ‘in’ the oxygen bond though - any more than when you have a ball at the top of a hill it has potential energy ‘in’ it.
Maybe I missed it but it's not a net positive output. From the article, the implication it is: "LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output" From newscientist, the same info followed by a rider: "generated a power output of 3.15 megajoules from a laser power output of 2.05 megajoules – a gain of around 150 pe…
This was explained by another commenter yesterday, but this is not an issue. The 3.15:2.05 ratio is the news as it is the part that was difficult to achieve. The 300MJ accounts for significant laser inefficiencies in much the same way that the 3.15MJ of output won't convert to 3.15MJ of electricity as the conversion is not loss less. In other words: it's a net-positive output for that reaction, not the whole process,…
> in much the same way that the 3.15MJ of output won't convert to 3.15MJ of electricity as the conversion is not loss less
...and very much touche! That's a good point. But I do feel the overall loss should have been made clear and distinct from the gain in one part of the whole. Gross vs net perhaps?
> LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE) Yesterday, everyone was complaining about the 2.2:2.0 ratio, but now we're working with 3.15:2.05. With modern lasers, that'd be a total Q of 0.375 assuming 100% ef…
The Q needs to be something like 500 to 1000, not because of energy breakeven, but to produce enough energy that the shot is financially positive. The amount of fusion energy produced in this shot is worth a penny or two. (And even then, it's dubious a laser fusion scheme will be competitive with other energy sources.)
Is there any calculation to this? What’s the cost of shot? Is there any limetime limit of the laser?
ELI5 level question. Please correct me if I'm saying something stupid. If you toss a solar mass of water into the sun it just becomes fuel. So, could a fusion reactor, when efficiency is improved, use water as fuel?
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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…
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The Q needs to be something like 500 to 1000, not because of energy breakeven, but to produce enough energy that the shot is financially positive. The amount of fusion energy produced in this shot is worth a penny or two. (And even then, it's dubious a laser fusion scheme will be competitive with other energy sources.)
Offset the financial viability with the cost of freedom from energy reliance and the need (more like craving) for military interventions
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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…
The wikipedia page is pretty good, as always: https://en.wikipedia.org/wiki/Nucleosynthesis
Almost everything with mass of 90 or above comes predominantly from neutron star mergers, basically.