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Fusion energy breakthrough by Livermore Lab

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Re: Fusion energy breakthrough by Livermore Lab

#121
post #77

Earlier quoted context omitted.

It's still decades off but as I understand it, this was the hardest nut to crack. They got what, 2.5 megajoules out of 2.1 in? I might be in the opposite camp as you but this is very much a "where were you when—" moment for me. I'm sure someone will pop in to disappoint me but I think the point is it's no longer a hypothetical exercise.

The net energy gain is very slim and has to be converted to electricity to power the lasers – in doing so, there's so much loss, it is again NEGATIVE. It's always the same…

As it always is with new, unproven things.

Re: Fusion energy breakthrough by Livermore Lab

#122
post #51

Even if fusion ends up producing more power than consuming in the real world, it still has to compete on cost. People too enthusiastic about fusion tend to ignore that it might not actually be a cost effective source of power. Solar panels are cheap and batteries are easier to build and there are lots of ways of making them.

Solar and wind are bad and unsustainable due to mining of rare earth minerals and photovoltaic cells degrading and becoming a landfill liability. Cost effectiveness is also a myth perpetrated by the death of nuclear executed through bureaucracy. The nuclear, however, is currently the true energy source to use, technologically much simpler (than fusion) to execute with decades of experience making it the safest out th…

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Re: Fusion energy breakthrough by Livermore Lab

#123
post #56
post #51

Even if fusion ends up producing more power than consuming in the real world, it still has to compete on cost. People too enthusiastic about fusion tend to ignore that it might not actually be a cost effective source of power. Solar panels are cheap and batteries are easier to build and there are lots of ways of making them.

Unfortunately, energy storage is still an unsolved problem. Research on batteries may get us there soon, but today they aren't feasible. It's very much worth putting effort into both approaches. IMO the best outcome is a wide variety of clean energy sources and storage solutions, so the best solution can be chosen for a given geographical/political/etc situation.

CATL is working on sodium batteries as a lithium replacement shipping in 2023

Form Energy is working on iron air batteries as a new class of multi-day energy storage, launching its first test installation in 2023

The US passed a tax credit for energy storage, to encourage building more pumped storage capacity

Congress is working on transmission line permitting reform

There are some good reasons to be optimistic in the near term

Re: Fusion energy breakthrough by Livermore Lab

#124

The net energy gain is very slim and has to be converted to electricity to power the lasers – in doing so, there's so much loss, it is again NEGATIVE. It's always the same…

This isn’t the same; this hasn’t been done before.

New things are hard. Nothing truly worthwhile is easy.

Re: Fusion energy breakthrough by Livermore Lab

#125

Earlier quoted context omitted.

I agree. There is no breakthrough on the horizon that is going to make a fusion plant have the complexity closer to a natural gas plant than a nuclear fission plant. Therefore the costs will remain high. It could still be a useful technology, especially in space. I could see a moon or mars base powered by fusion.

Gas has low capital cost but relatively high fuel cost, especially outside the US. For most fusion designs (possibly excluding NIF), the fuel cost is insignificant. Also of course we might want to consider the carbon emissions of gas plants.

That is what I mean. Some people are imagining the capital costs of a natural gas plant with the fuel and environmental costs being almost nothing. There is absolutely nothing to suggest that a fusion plant would cost anything less than a fission plant at this point.

Re: Fusion energy breakthrough by Livermore Lab

#126
post #102
post #74

Earlier quoted context omitted.

Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).

Why do we need to cover the worst case with 100% renewables? The goal is to reduce emissions so it would be great even if we can just stop burning coal in the summer.

Eventually we have to get to zero net carbon emissions. But the worst case is just to create carbon based fuels from CO2 extracted from the atmosphere and use it in places/for uses which cannot be covered by renewable electricity directly (the far north, airplaines, ...)

Re: Fusion energy breakthrough by Livermore Lab

#127

While I appreciate all the effort in nuclear fusion and do think we should continue to invest a little of each years global R&D budget, it seems these reactors (e.g ITER and this one) still require tritium which is rather hard to come by efficiently. Which means normal nuclear reactors will be needed to make it and minimising any economic viability of the dependent fusion rector for a long long time.

Normal nuclear reactors are a good thing too, and they alone are enough to solve all of humanity’s energy problems (though we should pursue fusion power too, of course). See Integral Fast Reactor.

Only if you use the notoriously dangerous breeder reactors – otherwise there isn't enough fuel.

Re: Fusion energy breakthrough by Livermore Lab

#128

Earlier quoted context omitted.

> They got what, 2.5 megajoules out of 2.1 in? Of laser energy into a tiny control volume that doesn't consider how much energy went into the laser systems. If you draw the control volume around the building and see that the lasers require vastly more energy than what came out, I think you'll be less excited, right? We've been getting lots of energy out of fusion since the early 1950s with thermonuclear bombs. We kno…

Could you elaborate on that? What do you mean that the lasers could require more energy? Is it that in a specific volume they got X EM energy coming in from the laser and Y thermal energy coming out, with Y>X BUT the electricity consumption of the lasers is Z>Y>X? If so that's sort of misleading, like the plethora of claims from ITER. I hoped this was different.

So the laser energy that went into the reaction in the form of light is less than what came out of the reaction. However, the energy needed to produce that laser energy may be orders of magnitude more depending on the laser. AKA: the Wall Plug Efficiency.

Tabletop rigs can be as efficient as 50%, however high power such as we see here tends to come with drastically reduced efficiency.

Re: Fusion energy breakthrough by Livermore Lab

#129

Earlier quoted context omitted.

> They got what, 2.5 megajoules out of 2.1 in? Of laser energy into a tiny control volume that doesn't consider how much energy went into the laser systems. If you draw the control volume around the building and see that the lasers require vastly more energy than what came out, I think you'll be less excited, right? We've been getting lots of energy out of fusion since the early 1950s with thermonuclear bombs. We kno…

Could you elaborate on that? What do you mean that the lasers could require more energy? Is it that in a specific volume they got X EM energy coming in from the laser and Y thermal energy coming out, with Y>X BUT the electricity consumption of the lasers is Z>Y>X? If so that's sort of misleading, like the plethora of claims from ITER. I hoped this was different.

Not /u/acidburnNSA, but what was meant is that no laser is 100% efficient. Not only do they not convert 100% of their electrical input into laser energy, but they also require other support systems, notably cooling. So we need to consider the total energy costs of the building the fusion experiment is conducted in, not just the physically small area where the fusion reaction is happening inside the reactor.

Still, this is an important step in the development of fusion energy reactors.

Re: Fusion energy breakthrough by Livermore Lab

#130
post #103

Earlier quoted context omitted.

I think fusion-plants have always been "15 years away", and most likely will be so for quite a few years... Edit: I was wrong, fusion is always 30 years away: https://www.discovermagazine.com/technology/why-nuclear-fusi...

I don't know what people get out of repeating this on every single fusion article. It's not inventive or insightful, and it doesn't further the discussion in the slightest.

Because it's A) true, B) relevant to keep all of the hype in check. The year of Linux on the desktop is always right around the corner too. Yes, they are tropes, but they were not born out of nothing.

Someone has to keep the bloviated PR campaigns checked with reality. Otherwise, some crazy fools might actually start believing that fusion is real and gets duped out of their money. If you can't stand a bit of real criticism, then maybe you should sell your scam somewhere else. Otherwise, take it on the chin, retool your message, and come at it honestly.

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