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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

#171

Post by pfdietz »

echelon wrote: post #105
pfdietz wrote: post #71

Earlier quoted context omitted.

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.)

It will get there. It's just a matter of time and resources. The destination will be a milestone for humanity, so we should not give up.

Why should I agree with this article of faith? The obstacles appear quite grave to me. Moreover, even reaching that Q doesn't mean we're there. That's a necessary, not sufficient, condition.

A large, complex machine that explodes the equivalent of 500 lb. bombs to generate heat to drive a turbine sounds like an engineering nightmare.

Re: US Department of Energy: Fusion Ignition Achieved

#172

Post by Alifatisk »

snshn wrote: post #94

I like how over 60 years after the nuclear boom, it somehow just happened to happen today. Just when the world is ready to transition to electric vehicles on a global scale, just when oil companies aren't able to make as much money from oil as they used to, just when one of the major suppliers of fossil fuels (Russia) is at war with the West, it has somehow magically happened. What a coinky-dink. Throw lots of money…

You're right when I think about it, the timing is amazing

Re: US Department of Energy: Fusion Ignition Achieved

#173

Post by aetherson »

wnevets wrote: post #84

I know this is from the DOE but is this real real or this is wormhole "real"?

It's not like the "wormhole" thing where what was produced isn't really what can plausibly be described as a wormhole. In this case, fusion really did happen, and the amount of energy produced by the fusion reaction was about half again what the energy put into the fusion reaction was.

That said, there are two pretty important caveats about how big a deal it is macroscopically:

1. In order to have useful fusion power, we'd need at least another order-of-magnitude or so energy out compared to energy in. Maybe, depending on how optimistic you are about the ability to capture that energy and efficiently feed energy in, closer to two orders of magnitude.

2. This is from an inertial confinement approach to fusion. Unlike the magnetic confinement approaches that we often hear about, this approach doesn't really create a continuously hot, spatially constrained bit of plasma that can then be used to heat things up -- it produces more like a small but intense explosion. There are real doubts about whether you can, even with very favorable energy-out ratios, industrialize that into an actual power plant. It's more challenging to harvest energy from an explosion than it is to harvest energy from a bunch of plasma flowing in a circle.

Re: US Department of Energy: Fusion Ignition Achieved

#174

Post by ceejayoz »

wernercd wrote: post #75
panosfilianos wrote: post #61

Earlier quoted context omitted.

Would that mean that you wouldn't need titium to start with? Or that tritium deposits would replenish? How would it affect the rough calculations above?

I would also wonder if Titium is that expensive... and it generates titium... would that be part of the "break even" equation? Creating something rare to sell?

Current demand is a couple hundred grams per year. We just don't need that much of it. The cost per gram would go down a lot if we needed to mass-produce it.

Re: US Department of Energy: Fusion Ignition Achieved

#175

Post by abecedarius »

brofallon wrote: post #30

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…

High power density. Start and stop on demand. Abundant fuel is another advantage, but in our neighborhood sunlight is also abundant. Fission also has good power density, but not so good on the start/stop flexibility.

Re: US Department of Energy: Fusion Ignition Achieved

#176

Post by happyopossum »

JohnBerea wrote: post #100

Let's say this all works out and over the next few decades fusion replaces all other electricity generation, and we're past the point where all the initial infrastructure costs have been paid for. How much will my electric bill be reduced?

This is kind of a silly question given the time horizons and other potential factors that can crop up in 30 years, but my electric bill has separate charges for generation and delivery. Even if generation drops by 90%, it'd still only cut my bill in half.

Re: US Department of Energy: Fusion Ignition Achieved

#178

Post by phasetransition »

spullara wrote: post #113
tgflynn wrote: post #111

Earlier quoted context omitted.

I wonder if it might be possible to gain not percentages but orders of magnitude more or less just by making the targets bigger. Is it conceivable that the same basic approach and a comparable amount of input energy could be used to ignite a 100 MJ or even 1 GJ target ? Of course that would present some containment challenges but perhaps not insurmountable ones. I'm also a bit concerned that this type of research may…

I mean almost all of the power in a nuclear bomb comes from fusion. The fission part of it is just like the detonator for the real explosion.

Almost all nuclear weapons rely heavily on fission of the tamper for yield.

Suggest "Ripple: An Investigation of the World’s Most Advanced High-Yield Thermonuclear Weapon Design" from the Journal of Cold War studies to read about a predominantly fusion device family.

Re: US Department of Energy: Fusion Ignition Achieved

#179

Post by sigmar »

micromacrofoot wrote: post #23
gjsman-1000 wrote: post #12

Earlier quoted context omitted.

Previous Fusion experiments, even though we could get Fusion reactions to occur, required more energy to start and sustain the reaction than was generated from it. For the first time, more was generated from the reaction than put in.

Note that while this is important progress, it's a bit of specific accounting. The entire system still requires more energy input than output, but this isolated piece can now output a little more than input. > This is indeed a promising and exciting result, but we need to remember that this does not take into account the energy required to run the lasers that confine the reaction and other inefficiencies and losses.…

Their goal was to produce a fusion reaction not to improve laser efficiency. That's a bit like complaining they didn't account for the energy used to structure the fuel. I don't think it's 'specific accounting' when (output/input)>1 was their goal from the start

Re: US Department of Energy: Fusion Ignition Achieved

#180

Post by chasd00 »

JohnBerea wrote: post #100

Let's say this all works out and over the next few decades fusion replaces all other electricity generation, and we're past the point where all the initial infrastructure costs have been paid for. How much will my electric bill be reduced?

i doubt your electric bill would be reduced at all. It would probably increase at a more constant rate instead of dramatic ups and downs though. So there's that..
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