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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

#521

Post by ClumsyPilot »

pfdietz wrote: post #171
echelon wrote: post #105

Earlier quoted context omitted.

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.

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

And using actual bombs and explosives to dig kilometers down and mine coal is not an engineering nightmare? Dying of gas in the mines, fires on oil wells, oil spills, these things are 'engineering simple'?

Re: US Department of Energy: Fusion Ignition Achieved

#522

Post by jackmott »

bmmayer1 wrote: post #103
jkelleyrtp wrote: post #33

> 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…

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?

No post body was provided.

Re: US Department of Energy: Fusion Ignition Achieved

#523

Post by krainboltgreene »

zaroth wrote: post #362
CuriousCosmic wrote: post #344

Earlier quoted context omitted.

yes. fusion funding has been sliding downwards for decades which is a large reason why it takes so long to do anything. It's largely the same reason why NASA takes so long to do anything. 1. Shortage of funding 2. failure can result in loss/exhaustion of funding 3. extremely low risk tolerance 4. physical experiments needing new HW only happen when the likelihood of success is extremely high 5. projects are over engi…

I can't agree that funding is "largely the reason" why NASA takes so long to do anything. I doubt funding is a top 3 reason. NASA just isn't about high-risk / high-reward "moonshots" anymore. The overarching political environment doesn't allow it, never mind the office politics. NASA will get back to the moon using easily an order of magnitude more funding than it should have taken, with a launch system that costs an…

> I can't agree that funding is "largely the reason"

> NASA just isn't about high-risk / high-reward "moonshots" anymore. The overarching political environment doesn't allow it, never mind the office politics.

Why doesn't the political environment allow for it. What could happen. What could regulatory bodies do to NASA for taking a risk and failing. What sort of constricting change could political bodies do in such a situation.

Re: US Department of Energy: Fusion Ignition Achieved

#524

Post by krainboltgreene »

BobbyJo wrote: post #422
zaroth wrote: post #362

Earlier quoted context omitted.

I can't agree that funding is "largely the reason" why NASA takes so long to do anything. I doubt funding is a top 3 reason. NASA just isn't about high-risk / high-reward "moonshots" anymore. The overarching political environment doesn't allow it, never mind the office politics. NASA will get back to the moon using easily an order of magnitude more funding than it should have taken, with a launch system that costs an…

Have to +1 this. A lot (most?) of NASA's funding is directed toward keeping people employed and skilled, as opposed to accomplishing goals, as with a lot of government money. NASA could do a LOT more with the funding they already have, if they were willing to divest from older technologies and vendors, but the politics of its funding doesn't allow that.

> A lot (most?) of NASA's funding is directed toward keeping people employed and skilled, as opposed to accomplishing goals

This is so hilarious wrong I don't even know where to start.

> but the politics of its funding doesn't allow that.

The post that you are agreeing with says that "funding" is not the reason for their plan.

Re: US Department of Energy: Fusion Ignition Achieved

#525

Post by gene-h »

onlyrealcuzzo wrote: post #282
gene-h wrote: post #108

Earlier quoted context omitted.

[0] provides economic analysis for this type of power plant. They conclude it would not be unreasonable to get levelized cost of energy could get as low as $25/MWh. For this one really needs a high gain of 1000, although gains of 400 are a bit more reasonable, and a gain of around 100 may be economically competitive in some cases. While the gain NIF achieved was about 1.5, there is good reason to expect it can be sca…

I think capital costs & construction times are going to be extremely important. I think the biggest reason nuclear energy stopped being built is it takes too long to get political wins. NuScale and other SMNRs might be able to help with that. However, the capital costs & construction time for Fusion Energy should theoretically be much lower than nuclear reactors. But are we too far away from it being a reality that a…

It will be quite difficult to make fusion cheaper than present day fission. Fusion reactors are new so significant research work will need to be done. There are difficult engineering challenges related to breeding fuel, which involves moving hot, radioactive, and water reactive molten lithium around. Fusion reactors need to be built to high tolerances and will need to be refurbished occasionally due to radiation/heat and in the case of NIF style fusion, explosion damage.

And one still has to deal with many of the same radiation challenges fission plants must deal with. A large quantity or radioactive tritium must be kept on site and neutrons from the fusion reaction will make the reactor radioactive. In fact, fusion produces more neutrons than fission per unit energy. Even so called 'aneutronic' fusion would have side reactions which would produce quite a lot of neutrons.

Fusion is a lot more complicated than using special rocks to boil water.

The main advantage of fusion is a political one. It politically nigh impossible to build a fission reactor in a suburban industrial park, but Commonwealth Fusion Systems is doing exactly that with a fusion reactor[0]. And there is also the slim possibility this type of reactor could explode. Said reactor uses superconducting magnets which store a lot of energy and if something goes wrong, it would be possible for them to release that energy fast.

But, the NRC hasn't made laws for regulating fusion power yet, so they are able to do this.

[0]https://cfs.energy/news-and-media/commonwealth-fusion-system...

Re: US Department of Energy: Fusion Ignition Achieved

#526

Post by joosters »

IgorPartola wrote: post #498
jkelleyrtp wrote: post #33

> 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…

I keep getting lost in the numbers here. What was the net gain/loss for the entire system? Without the “lasers are 1% efficient at 20% energy loss with 40% energy transfer loss” and all that.

They needed roughly 500MJ of energy to power the lasers and produce the 2.5MJ of energy, so the net loss was... about 500MJ.

Re: US Department of Energy: Fusion Ignition Achieved

#527

Post by 988747 »

ClumsyPilot wrote: post #508
beowulfey wrote: post #312

Earlier quoted context omitted.

It’s a proof of concept. Upgrading lasers that already work is not necessarily the best use of limited funds.

They could get higher power out of more efficient lasers, enabling research at higher energies or bigger targets

Not to mention the money they would save on electricity bills.

Re: US Department of Energy: Fusion Ignition Achieved

#528

Post by zbobet2012 »

IgorPartola wrote: post #498
jkelleyrtp wrote: post #33

> 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…

I keep getting lost in the numbers here. What was the net gain/loss for the entire system? Without the “lasers are 1% efficient at 20% energy loss with 40% energy transfer loss” and all that.

The net gain of the entire system at NIF doesn't matter, because the system at NIF was never designed to make a net gain.

People are estimating how this result moves the equation for an overall system that is designed for power production. Most numbers I have seen still leave a theoretically optimal power plant producing around a 30% loss in power with this number.

Re: US Department of Energy: Fusion Ignition Achieved

#529

Post by steve76 »

bmmayer1 wrote: post #103
jkelleyrtp wrote: post #33

> 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…

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?

No post body was provided.
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