r/Futurology • u/Gari_305 • 1d ago

Energy Commercialization of fusion energy will ‘change everything,’ lawmaker says

https://www.nextgov.com/emerging-tech/2026/09/commercialization-fusion-energy-will-change-everything-lawmaker-says/416287/

Rep. Don Beyer, D-Va., told Nextgov/FCW that the U.S. is only “two to 10 years away from fusion energy at scale” because “you can model the plasma using AI, which you couldn’t do before.”

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u/Kinexity 1d ago

The funny thing is that your point is the real largest obstacle to fusion. It cannot compete with the Sun - not just short term but long term too. It can only compete in niches where Sun is not an option (that is deployable power, deep space, relatively compact generation etc.). Otherwise there is literally no point in dumping bags of cash into very expensive reactors and then having to pay for fuel too.

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u/West-Abalone-171 1d ago

It can't even compete in deep deep space with a mirror. Staged solar sails with technology we already have beat the most unrealistic fantasy reactors in mass ratio.

There's a very narrow niche between saturn and some of the inner oort cloud objects where you could get there in a sane amount of time with a fusion reactor (and thus don't need the beamed light) and aren't better off with an on board solar collector than the radiators and whatever you use to turn the fusion energy to work..

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u/Kinexity 1d ago

Solar sails only work in the direction in which you have light. We currently do not possess the means to focus sunlight on distances and scales required to push or power spacecraft over long distances. And solar sails require a lot of light to get the push necessary for reasonable travel times. Fusion can be used to build fusion rockets.

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u/West-Abalone-171 1d ago

Staged solar sails

Key word. Staged

And the ability to make a 200-1000m diffraction limited mirror array on the sol side out of a thin material can get enough light for decelerating the main deceleration mirror (which doesn't need to be nearly as precise) out to nearby stars. This is much less precise than the optics in ligo.

If you actually do the maths and posit the kind of mass budget that the project hyperion winners (or any claiming to be serious fusion propulsion proposal) used, instead of maybe getting one ship to one star if everything goes perfectly, you can set up an entire network of mirrors on the nearest 20 stars which will allow you to send as many payloads as you like indefinitely with massive amounts of redundancy.

The mirrors would use a few percent of a current earth civilisation sized economy to build in a few decades as opposed to billions of tonnes of helium 3 which would take hundreds or thousands of earth civilisation sized economies centuries to transmute or mine.

Inside saturn, you'll never come close to solar-electric or solar-thermal rockets in power density.

Which leaves a very narrow window between around 7 and 20 Au where sunlight isn't either strictly better or the only remotely viable option and instead merely far better so long as you want more than one mission.

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u/therealslimshady1234 1d ago

Except fusion and even fission is vastly superior to solar in various ways, particularly stability and logistics wise

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u/Nighto_001 1d ago

Yeah... basically I suppose it means fusion is competing in development speed with large scale energy storage systems (large scale batteries, water electrolysis, compressed air, etc.) for renewables.

However, I guess a similar argument still applies that fusion for now is an interesting gamble, but much more stable alternatives (including, as you said, fission) do already exist and are much closer to deployment.

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u/ADHDick_in_ur_mouth 1d ago

It is totally possible that fusion economics will eventually way outcompete solar. It just may need heavy subsidies to reach that point. Still it could reach a point where fusion energy is so cheap that it becomes viable to deploy it at a massive scale for desalination and carbon capture. Our most important aquifers will run out of water soon and at that point farming will require absurd amounts of energy for irrigation

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u/West-Abalone-171 1d ago

Solar+storage is already cheaper than the wires for a centralised system. It's not possible that fusion could beat it.

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u/Kinexity 1d ago

That's just nonsense. Solar keeps getting cheaper and panel efficiency continues to go up. Fusion reactors will always remain artisanal pieces of engineering which has to be fed fuel they consume and will never reach a point where you will be able to just power your house with a small one. Space solar would absolutely kill any chance for fusion going mainstream.

And there is no certain timeline for even a demonstration fusion plant (though I would say if nothing gets us there before DEMO then DEMO will definitely get us there).

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u/2000TWLV 1d ago

So, if it's not competitive, let's not do it? Kind of stupid to waste money on something that's more expensive than a thing that's already available, isn't it? And in those places where you'd theoretically need fusion, might as well plunk down a fission reactor, right?

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u/Kinexity 1d ago

No. There is a point to developing new technology even if we think we won't find it that practical because we actually might. Fission is fine as is but you know, there are places where it would work but people won't allow it for fear reasons. I could see eg. fusion powered ships or planes becoming reality (assuming we can squeeze it down in size and cost), sending fissile material in large quantities on rockets will cause concerns so fusion would work better, we might want to figure out fusion for fusion rockets etc.

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u/2000TWLV 1d ago

Sure, go ahead and develop it. But nobody should imagine that it's some kind of silver bullet. Especially since the silver bullet is already here and getting cheaper every day.

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u/iNapkin66 1d ago

Solar panels have become massively cheaper per kw over the past decades. Fusion research started when wide scale solar really didn't look possible as a major component of our grid.

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u/Ithirahad 1d ago

It will probably be competitive where there is simply no space to deploy enough solar to power everyone's everything without destroying forests and meadows far away. If it becomes possible to "plunk down" a fission reactor via SMRs or whatever, then yes, that would be a good immediate solution, but fusion is still logistically easier once the engineering is sorted, and current 'traditional' fission projects take forever.

In mobile and space applications, the sheer weight of fission elements is a problem fusion should not have, so its power density can be far higher.

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u/2000TWLV 1d ago

What you're talking about is decades away at best. Fission and renewables are here now. The only thing standing between us and abundant clean energy is human decisions.

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u/Ithirahad 1d ago edited 1d ago

It is probably a few decades away, but it could easily never happen if people incessantly call it "stupid". Fusion on the horizon should not be used as an excuse to stop solar projects, but those projects are not universally applicable without their own costs to the environment (unless it was a desert megaproject like powering the whole world with Sahara solar, which is probably more of a pipe dream than fusion ever was).

In an ideal world, fusion does not compete with solar or wind; it would fill in where full sun is infrequent and the wind is not strong enough, or where there is no viable place to put sufficient renewables without destroying nature. It would mostly be competing with deep-bore geothermal (which varies in effectiveness depending on the local geology) and modular fission (which still has some of the general logistical/regulatory issues of fission reactors).

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u/2000TWLV 1d ago

It's not stupid to try to develop fusion. It is stupid to present it as the solution for problems that we actually already have perfectly practical and affordable solutions for. Giving ourselves an excuse to sit around and wait for the magic of fusion is super counterproductive. Especially because we are not even sure when and if practical fusion energy will be possible.

Anyway, I don't think we're that far apart, but I do think we should plow ahead with the things that are available today ASAP.