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.)
Its worth pointing out that per unit energy a lot of money is made making economically unviable cargo ship power, submarine and other military naval power, space ship power sources, diesel-electric locomotives ...
True if you want to replace base load of a civilization size network it needs to be economically viable, but we generate "a lot" of power at higher than market minima. Ironically, "good batteries" are the natural enemy of fusion research.
One fun thing about laser fusion is it theoretically can scale down very low and has a trivial "off" switch making it a good resource for engineering tokamak reactor materials or sensors or similar tasks.
The inner lining of a production fusion reactor is hard to make, so a laser facility would be ideal for research. Which is why we have one...
DT fusion reactors would be terrible for mobile applications, since there are so much larger than fission reactors of the same capacity. In space or mass constrained applications they would be ruinously inferior to fission.
Inertial confinement fusion requires fairly expensive targets to collapse. To make it economically viable they have to produce a lot more energy per target destroyed.
The targets are only expensive because they aren't produced at scale yet.
They are the exact kind of thing a machine could churn millions of per day out, and then use them at the same rate.
Even if the targets were made of expensive materials (eg. platinum), most of that platinum could later be recovered from the reactor wall, so it still wouldn't be very expensive.
"most of that platinum could later be recovered from the reactor wall, so it still wouldn't be very expensive. "
And recovering comes for free?
Every step costs energy (or money).
There is no working design yet. It is waay too early to make any predictions about how scaling could reduce costs. Scaling can even increase costs, if it depletes limited resources like tritium.
It will get there, but it won't be from NIF or via any technology developed for this experiment. What they are doing is not viable for a rector, won't ever be viable for a reactor, and won't even be considered a starting point for any future rector.
It's a fusion plasma research experiment. It's not a program that is being run with the goal of creating a usable fusion energy power plant.
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.
Because sustainable positive energy out has never been achieved before in 60 years of research. This is gigantic. It’s potential to decarbonize the world is massive, and now it became a whole lot less theoretical.
It’s an incredible milestone, not a solved problem.
That's a circular argument. It's big because the people doing it call it big. Why should I, an outsider, care about their internal goals, their egoes, or their status in their field? What does it do or imply for me?
To achieve fusion for power production, you need more output than input. For 60+ years this hasn’t been achieved in a replicated fashion. Now it has, and it’s 50% more power rather than 0.1% more power as was sometimes shown for 2 nanoseconds before. So now we know fusion for power is possible. If it can be scaled successfully (now likely not an if anymore, but a function of time), then we have the ability to have clean and safe energy 24/7. That would help mitigate the worst of climate change, and if cheap, turbocharge the entire economy.
The issue is, we've been able to get more energy out of a fusion reaction than put in for 60-70 years now. The H-Bomb is very good at doing that. You will say, yeah, but an H-Bomb is a one time use thing, and it has a habit of destroying everything. If you look into how the second stage of an hbomb is speculated to work, its pretty much identical to this experiment, that is by design, not by accident.
Herrmann acknowledges as much, saying that there are many steps on the path to laser fusion energy. “NIF was not designed to be efficient,” he says. “It was designed to be the biggest laser we could possibly build to give us the data we need for the [nuclear] stockpile research programme.”
I'm asking why this somewhat arbitrary line being crossed is something I should care about. It doesn't imply fusion will reach a state of practical application. Why is this more exciting that achieving a ratio of .1, or .5, or 2, or 10? It seems entirely arbirary to me, and smells of an argument that somehow this has made the end goal significantly more attainable.
>why this somewhat arbitrary line being crossed is something I should care about.
That is something personal and unique to each individual. In 1903 when the Wright brothers flew a heavier-than-air machine for 59 seconds, 99.99999% of the people on the planet wouldn't have cared. The airplanes you've flown on are vastly far removed from that original one. Same story for the point contact transistor in 1947. None of that solid state physics is used for modern transistors. Some people like to be early adopters for new ideas and things. Some don't. And that is OK.
Because until now contained ignition has never produced anything meaningful. We've had failed experiment after failed experiment. Now we finally have an experiment with a meaningful more amount of energy out than in.
Is this the right approach? Who knows. There are many fusion designs in the works, and those may ultimately be the right call. Or some yet-to-be-created design. That's even probable. The NIF is for simulating nuclear weapons, not creating energy. None of that takes away from this breakthrough - we've never had meaningfully more output than input on a repeatable basis. It's proof that contained fusion for energy isn't just hypothetical, which will also mean funding & interest will generally increase from this point on.
I think you're setting too high a bar. It's like saying no milestone should be celebrated until we have a working metropolitan-size plant running that's cheaper than anything else. Punch cards in the 1950s are insignificant compared to modern SSDs, yet they were an important step even though we don't use anything like it now. Breakthroughs are breakthroughs.
> It's big because the people doing it call it big.
How does "[It's big b]ecause sustainable positive energy out has never been achieved before in 60 years of research" translate to "because we say it's big" in your head?
You might not consider it big, but a specific reason was provided and it had zero similarity to your rephrasing.
An answer matched in tenor and tone to the question, but nonetheless entirely serious,
is that because while the obstacles are grave, the consequences of failing to overcome them are much graver still,
and to the best of our collective knowledge,
industrial scale fusion would be the least bad answer to our energy demands for the next epoch.
That is true but also does not obviate the need for other parallel efforts and other technologies whose challenges are also very grave, e.g. the need for very near term very large scale carbon sequestration, for a modern electrical grid with deep redundancy and resilience, the need for effective safe scalable stores for energy from whatever source, etc.
While I'm sure that you're correct, the obstacles are large and there is a lot of overcome still, I can't help but think of James Watt & (my ancestor) Richard Trevithick - the inventor/pioneer of the compact steam engine.
Watt went around telling everyone that Trevithick and his compact (ie high pressure) steam engines were too dangerous and would never work.
Yes, some exploded. But then we got steam trains and even today almost all power generation on the planet is high pressure steam-electric power plants.
> 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'?
We don't place precision optics in those blast zones. We don't put structures there that are repeatedly exposed to blast. Over the life of a inertial DT fusion reactor there will be about a BILLION such explosions in the reactor core.
Q is irrelevant, you need throughput. If your Q is one million, but you are processing one tiny capsule per second, you are producing too little money to pay for the facility.
If you can process a tanker worth of hydrogen per second, Q can be just above break even and you will still make money.
Irrelevant? Seems like Q is one of two factors in that calculation. If the throughput is tiny, you're useless, but if your Q is too small, the same is true.
The higher the Q, the lower throughput needed for feasibility.
Exactly. Beyond power generation, humanity still uses petroleum products in their chemical industry. Which is why the shutoff of Russian natural gas hurts Germany much more than other countries, they now have a starving chemical sector.
I'm confused by this. Does the US have the productive forces and resources to replace petrolium with solar panels (and the required energy storage)? Does it have the nuclear fuel to replace petrolium with fission reactors?
What alternatives to petrolium does the US have that it does not rely on others for?
What scheme do you imagine that fusion could be used to replace petroleum that would not also work when powered by solar? Production of synfuels using hydrogen, for example, would also deal with solar's intermittency, leaving the energy sources to compete on the basis of levelized cost. The levelized cost of solar has become quite low, and it's very difficult to see how any fusion scheme, and DT fusion in particular, will ever compete.
I specifically asked about the production of solar panels. Are you assuming that we already have all the panels we need to replace petrolium sitting in a warehouse? What good is solar in an energy independence plan if we can't build our own panels?
Nuclear fuel actually isn't that expensive or rare
Those crazy sci-fi stories from the 30s and 50s where everyone used nuclear power (and it was so cheap they didn't bother to meter it) were all completely accurate from a non-political viewpoint
Foreign energy reliance is finished and has been for some time. North America can produce more petroleum energy than it uses. In both 2020 and 2021 the US was a net petroleum exporter.
(And even then, it's dubious a laser fusion scheme will be competitive with other energy sources.)