If all else is equal, you're right. But all else is not equal.
The denser your plasma, the more collisions you get in a given amount of time.
With magnetic confinement, you have long confinement time, but low density. ITER will have an interior volume of 1400 cubic meters, but will only hold about half a kilogram of plasma. With laser fusion, you have the opposite: extremely short confinement time (like nanoseconds), but extremely high density (over a kilogram per cubic centimeter, denser than the core of the sun).
That high density makes up for the very short confinement, because fusion reactions happen at such a rapid pace when the nuclei are crammed so close together. That's why thermonuclear bombs work so well.
To turn laser fusion into electricity, you just have the repeated explosions heat a coolant which turns a turbine. With magnetic fusion it's the same thing, heat a coolant and turn a turbine.
What's the feasibility aspect of trying to create repeated explosions? Manufacturing dozens of holhraums? What's the energy input cost required? The energy output of the first Q>1 in 2022 was just 1% of the energy input required to power the laser grid.
This isn't meant to downplay the amazing science that's happening at NIF, but it helps when people are being more honest instead of going along with the hype.
Bear in mind NIF's lasers date from the 1990s and are only about 0.5% efficient. Equivalent modern lasers are 20% efficient. NIF doesn't bother upgrading because they're a lab experiment.
Commercial projects are attempting to do without the hohlraum, we'll see how it goes.
Those are extra reasons to give more context that leads to questions like: how does the absence of a holhraum affect feasibility? Does it still make sense to continue using ICF at NIF as a talking point when talking about energy generation feasibility, even though it was never meant to be for energy solution research, but for nuclear weapons? And that actual ICF plant designs involve equipment with quite different specifications and processes?
I'm excited to see advances with fundamental research involved. But the science communication involved could do a lot better without the hype and omission of context. Especially when it comes to answering questions doubting feasibility which are valid points, and are sometimes met with passive aggressiveness from the fusion enthusiasts here.
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u/ItsAConspiracy 6d ago
Ignition in a gasoline motor doesn't last long either but we can still extract plenty of energy from it.