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Comment by femto113 | Hacker News Reader

Scaling the NIF's approach (laser inertial confinement) isn't about more reaction mass per pulse, it's about more frequent pulses, and is probably not going to be practical or cost effective in the foreseeable future. The fuel pellets are tiny (~2mm), their container is only about 1cm and must be nearly perfectly spherical. A continuous power plant would consume about half a million of them per day (6 per second), all of which need to be shot with perfect timing, precision, and reliability to the exact center of the laser sphere. My guess is magnetic systems are much more likely to ever be used in power generation.

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This feels important. We already know that fusion "works" (proof: look up). But it's not possible to recreate the conditions of a star on Earth. So if this method is also impractical, why would I care that it "works"?

Scientifically it's potentially very interesting: close up observation of what's going on in the center of a star and all that. I'd ignore all "the future of free clean energy is upon us at last!" hype. That's the lab and the government officials trying to drum up publicity that can then be milked for financial/political capital (it costs many billions to build and run a facility like this), coupled with lazy news outlets trying to milk sensationalist headlines for eyeballs.

This seems far more credible than the "This means fusion in ten years!" hot takes, which are - frankly - completely implausible, whether they're coming from physicists or journalists.

Weapons research might be a motivator too.

I would be astounded if this can be commercialised. Not because I'm cynical for the sake of it, but because I cannot in good faith see a credible engineering path which might make that possible without spectacular breakthroughs in a number of disciplines.

MCF seems more likely to get somewhere. But my best guess is that advances in renewables will have made fusion redundant within ten years. There is far more scope for incremental and affordable improvements in collection, distribution, and storage than there is for the Big Science breakthroughs required to build one commercially viable ICF plant.

Funding for NIF is 100% about weapons, it's never been about energy. After '97 (when Clinton signed the CTBT and the US agreed to stop testing new weapons) the national labs were in a panic until some clever DOE wonk invented the concept of "stockpile stewardship" and they went back to business more or less as usual.

If you create an impractical mechanism to prove out a scientific problem, you know it's then worth trying to fix the impractical mechanism. Maybe they start working on a way to direct the pellets into the correct path using magnets or something. But if you don't even know the scientific part works it's not worth going after the magnet solution.

I think OP's point is that the sun already presents itself as an impractical mechanism

It's easy to argue that an impractical mechanism we know how to make is easier to modify and refine into a practical mechanism compared to an existing impractical mechanism we don't know how to replicate.

It proves that net positive fusion is achievable here with known physics and technology (outside bombs which are useless).

We had never done that before.

This will probably unlock more funding. In the end a different approach is probably more likely to lead to a power plant unless truly gigantic advancements in laser efficiency can be achieved.

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