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Progress toward fusion energy gain as measured against the Lawson criteria

fusionenergybase.com

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Re: Progress toward fusion energy gain as measured against the Lawson criteria

#91

Post by boxed »

DennisP wrote: post #16
CGMthrowaway wrote: post #15

I heard that NIF was never intended to be a power plant, not even a prototype of one. It's primarily a nuclear weapon research program. For a power plant you would need much more efficient lasers, you would need a much larger gain in the capsules, you would need lasers that can do many shots per second, some automated reloading system for the capsules, and you would need a heat to electricity conversion system around…

It's an experimental facility. Yes, a power plant would need much more efficient lasers, but NIF's lasers date back to the 1990s, equivalent modern lasers are about 40X more efficient, and for an experiment it's easy enough to do a multiplication to see what the net result would have been with modern lasers. Modern lasers can also repeat shots much more quickly. Power gain on the capsules appears to scale faster than…

From what I understood, laser fusion needs laser efficiencies not just 40x better than what NIF uses, but like 3 or 4 orders of magnitude more efficient than the state of the art. Seems like a non-starter.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#92

Post by russdill »

dale_glass wrote: post #34

It should be noted that "breakeven" is often misleading. There's "breakeven" as in "the reaction produces more energy than put into it", and there's breakeven as in "the entire reactor system produces more energy than put into it", which isn't quite the same thing.

It's always confused me a bit. It's not like if you put 10kWh into the reactor, that 10kWh goes away. You still lose a significant fraction of it in inefficiency of the cycle but it still goes towards heat which can be used to heat steam and turn a turbine. iirc, you can get about 4kWh back.

On the other side of the coin, if you put 10kWh in and get 10kWh of fusion out, that's 20kWh to run a steam turbine, which nets you about 8kWh. So really you need to be producing 15kWh of heat from fusion for every 10kWh you put in to break even.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#93

Post by Kubuxu »

adgjlsfhk1 wrote: post #86
UltraSane wrote: post #81

Earlier quoted context omitted.

I am so tired of this lie being repeated endlessly. We have a perfectly safe way to handle nuclear "waste": reprocess the dirty fuel and bury the actual waste deep underground like Finland is doing at the Onkalo spent nuclear fuel repository. https://en.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_repo... And there is still very much a need for zero-carbon DISPATCHABLE electricity of witch nuclear is the ONLY choice.…

hydro is also a 0 carbon dispatchable choice (which is much cheaper)

Majority of good spots for hydro were already built up, and if they weren’t, good luck with NIMBY.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#94

Post by internet_points »

dale_glass wrote: post #34

It should be noted that "breakeven" is often misleading. There's "breakeven" as in "the reaction produces more energy than put into it", and there's breakeven as in "the entire reactor system produces more energy than put into it", which isn't quite the same thing.

and then there's "breakeven" as in "it pays for the investment within X years"

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#95

Post by worik »

UltraSane wrote: post #81
worik wrote: post #79

Earlier quoted context omitted.

I will bite. There are any problems with fission that are all related to the extraordinary danger of handling the fuel, byproducts, and the sites themselves. The cost of them is huge, some people are hoping that modularity will help with construction, but it is still astonishingly expensive. The problems of handling the fuel has been solved, in theory and practise. Except when commerce is involved. When the money peo…

I am so tired of this lie being repeated endlessly. We have a perfectly safe way to handle nuclear "waste": reprocess the dirty fuel and bury the actual waste deep underground like Finland is doing at the Onkalo spent nuclear fuel repository. https://en.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_repo... And there is still very much a need for zero-carbon DISPATCHABLE electricity of witch nuclear is the ONLY choice.…

> bury the actual waste deep underground

How deep, to stay put thousands of generations?

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#96

Post by ViewTrick1002 »

worik wrote: post #77
PaulDavisThe1st wrote: post #64

Earlier quoted context omitted.

I am no fan of fission (I strongly oppose new fission plants). But one problem with solar+storage is that the cost of the storage component increases roughly linearly with the desired storage duration. That's not true of a fueled power plant (fission or fossil).

Where are the flow batteries? (fuel cells) Lithium ion batteries are light with a high energy density, so are great for cars. Flow batteries have a low energy density, but increasing the duration means a bigger tank, and the cost of bigger tanks increases as a function of the cube root (?) of their volume Flow batteries are well over a century old, but I have been reading about improvements over the last two decades.…

Having trouble staying ahead of the enormous monster that is the lithium battery industry which through sheer scale are lowering the costs allowing it to break into one market after another.

It is the good old: Good enough beats theoretically perfect.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#97

Post by mapt »

Anyone have any idea where First Light Fusion's third machine fits into this?

The idea of using literal guns (gunpowder, then light gas gun, then coil gun) to impact projectiles against each other seemed like it was probably ludicrous, but I haven't seen any critical media or numbers yet.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#98

Post by willis936 »

russdill wrote: post #92
dale_glass wrote: post #34

It should be noted that "breakeven" is often misleading. There's "breakeven" as in "the reaction produces more energy than put into it", and there's breakeven as in "the entire reactor system produces more energy than put into it", which isn't quite the same thing.

It's always confused me a bit. It's not like if you put 10kWh into the reactor, that 10kWh goes away. You still lose a significant fraction of it in inefficiency of the cycle but it still goes towards heat which can be used to heat steam and turn a turbine. iirc, you can get about 4kWh back. On the other side of the coin, if you put 10kWh in and get 10kWh of fusion out, that's 20kWh to run a steam turbine, which nets…

Cars are a good analogy. You wouldn't talk about miles per gallon until you have an engine that idles. Humans are in the engine building phase.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#99

Post by willis936 »

UltraSane wrote: post #23

The money being spent on fusion should be being spent building next generation fission power plants and liquid salt reactors.

If you took all the money in the world being spent on fusion research right now you would struggle to build a single 1 GWe fission power plant. That doesn't sound like an improvement in resource allocation to me.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#100

Post by hypercube33 »

lotharcable wrote: post #69
__MatrixMan__ wrote: post #38

Earlier quoted context omitted.

Nothing about the NIF looks like a power plant to me. It's like the laser weapons guy and the nuclear weapons guy found a way to spend giant piles of money without having to acknowledge the weapons angle.

Yes. The NIF is a weapons research lab, not a power research lab. The purpose of it is to show that the USA is still capable of producing advanced hydrogen bombs. More advanced then anybody else. The '2.05 megajoules' is only a estimation of the laser energy actually used to trigger the reaction. It ignores how much power it took to actually run the lasers or reactor. Even if they update the lasers with modern ones t…

It's been over 20 years since ive dug into nuclear tech pretty deep but - don't we already have breeder reactors and other tech that is low waste, safer and thus we could build modern (not based on nuclear submarine) reactors in the fission category and deliver cleaner power, today? Yes there is a lot of politics especially around manufacturing, production and storage of spent fuel so all of those are probably show stoppers no matter how safe they are in reality but we aren't invested in it.
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