this post was submitted on 02 Apr 2025
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The fusion-fission hybrid will use high-energy neutrons produced by a fusion reaction to trigger fission in surrounding materials thereby boosting energy output and potentially reducing long-lived nuclear waste.

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[–] milicent_bystandr@lemm.ee 4 points 2 days ago

fusion-fission power plant

Sounds like you're just undoing your work. Put the pieces together, take them apart again. Energy!

Wake up babe new perpetual motion dropped!

[–] Warl0k3@lemmy.world 70 points 4 days ago (3 children)

This... seems... highly theoretical.

[–] Quazatron@lemmy.world 38 points 4 days ago (1 children)

It's... It's well within limits. Sustaining sequence.

Oh. Oh dear.

[–] Simulation6@sopuli.xyz 7 points 3 days ago

Is that a resonance cascade? Don't see those every day.

[–] MangoCats@feddit.it 4 points 4 days ago

I'd like to see a followup story published sometime other than the first of April.

[–] CosmoNova@lemmy.world -2 points 4 days ago (2 children)

Well you see. Mega projects in authoritarian countries rarely solve actual problem or serve a purpose. They‘re just there to make good headlines and be forgotten because the next mega project or innovation just made the news!

[–] Wobble@lemmy.dbzer0.com 12 points 4 days ago (1 children)

Are we saying things like the three gorges dam, china canals, and rail, are all just for show and don't serve a purpose?

[–] balder1991@lemmy.world 2 points 4 days ago

It’s more accurate to say they might be, but not necessarily. China is very aware of the benefits of keeping ahead technologically.

[–] singletona@lemmy.world 33 points 4 days ago (1 children)

OK. Here's the real question.

Are they sharing that research? I ask because if we can all get our heads out of our asses on energy production that kinda... wipes out a major reason for wars. Oh sure there are lots of OTHER reasons, but getting that off the table of excuses would be nice.

Also using fission materials as a way to shield the fusion reaction is a damned interesting way of getting around the spalling problem of the fusion reaction destroying its containment walls.

[–] AngryCommieKender@lemmy.world 17 points 4 days ago (2 children)

I'm pretty sure they aren't doing the design part of the research. A lot of the "new" designs that China has been testing recently, have been sitting on US and European shelves for decades, like since the late '60s and early '70s. There's just not really a way, in the West, to legally set up a test reactor. China can just ignore things like permits and zoning.

[–] cynar@lemmy.world 12 points 3 days ago

This is one of the biggest frustrations with nuclear power. The first power plants had issues (mostly due to them being bomb factory designs). We learnt from that, and designed better ones. They never got built. They were swamped in red tape and delays until they died.

Decades later, China comes in and just asks nicely. The designs work fine. China now leads the way, built on research we left to rot.

It's also worth noting that there is a big difference between a fusion power plant and a fission one. China is doing active research on it, as is the west. There's quite a friendly rivalry going on. We have also basically cracked fusion now. We just need to scale it up. The only big problem left is the tokamakite issue. The neutron radiation put off by the reaction transmutes the walls. Using radioactive materials as a buffer is an idea I've not heard of. I'm curious about the end products. A big selling point of fusion is the lack of long term waste. Putting a fission reaction in there too might lose that benefit.

[–] singletona@lemmy.world -2 points 4 days ago (1 children)

permits, zoning, human lives, environmental concerns...

Here's hoping it doesn't go boom.

[–] MangoCats@feddit.it 5 points 4 days ago (1 children)

They don't usually go boom so much as ticky ticky ticky on the Geiger counters, maybe a little glow in the night too...

[–] FordBeeblebrox@lemmy.world 10 points 3 days ago (1 children)

The likelihood of one blowing its top is about as likely as the front of a boat falling off, which I’d like to make clear is very uncommon

[–] pulsewidth@lemmy.world 3 points 3 days ago (2 children)

Not sure if you're being sarcastic but boats splitting in half is not uncommon, as far as boat structural failures go it's a relatively common one.

Stats on such a thing are unavailable but there are many news articles regarding boats splitting in half. I'd hope the safety factor on a fission reactor is several orders of magnitude higher than a seafaring vessel.

https://www.marineinsight.com/videos/why-do-ships-break-from-the-middle/

[–] MangoCats@feddit.it 1 points 2 days ago

That depends... do you count tsunami? Operator error? Design hubris?

All told, I wouldn't be surprised if a greater percentage of reactors have melted down than big ships have split at sea.

[–] troed@fedia.io 27 points 4 days ago (1 children)

In the sense that it does use more of the fuel, like a breeder reactor, that's good. We need to stop claiming 95% good fuel to be "waste" that needs to be stored for a long time and instead just use it all up.

[–] Fermion@feddit.nl 4 points 4 days ago* (last edited 4 days ago)

The other benefit I can think of is keeping the fissile materials always sub critical. You don't have to worry about a meltdown if the reaction is not self-sustaining. It's an odd marrying of technologies, but I think people are being too dismissive.

Although, I wonder if the true purpose of such a device would be high output breeding of fuel for weapons use.

[–] Ledericas@lemm.ee 6 points 3 days ago (2 children)

also known as a hydrogen bomb.

[–] HeavyRaptor@lemmy.zip 13 points 3 days ago (1 children)

It seems like the opposite: fission triggered by fusion

[–] eleitl@lemm.ee 1 points 3 days ago

Yes, the uranium tamper in a fusion weapon. Half of the energy in a fusion weapon comes from fast neutron fission, mostly in U-238. It's not a chain reaction.

[–] endofline@lemmy.ca 2 points 3 days ago

This is uncontrolled reaction. Chinese and other countries plan to be able to conduct the controlled reaction

[–] ProphetAlex2@lemmy.world 19 points 4 days ago (1 children)

So it’s a fission reaction boosted by fusion?

[–] Allero@lemmy.today 18 points 4 days ago

Essentially yes.

Normally, the amount of neutrons generated in a fusion reactor is an issue. Here it is an asset.

[–] Badabinski@kbin.earth 9 points 4 days ago

Huh, sounds like a neat twist on the accelerator driven subcritical reactor. I've no idea what the viability will be, but it also seems like a nice way to generate useful isotopes for nuclear medicine and shit.

EDIT: ah, it's actually a pretty old idea, it predates the accelerator reactor concept by quite a bit.

[–] peoplebeproblems@midwest.social 10 points 4 days ago (2 children)

Wait wait wait wait.

Don't we already do this? Just right now we don't do it in the same reactor?

[–] AngryCommieKender@lemmy.world 5 points 4 days ago* (last edited 4 days ago) (2 children)

Not that I'm aware of. All our nuclear commercial power plants are just plain old nuclear energy boiling water. We're gonna use a damn Dyson Sphere to boil water......

We have bombs that use a similar starting mechanism, but they aren't exactly useful energy production.

I meant that we use neutron breeders to turn certain fuel rod waste into fissile plutonium I think.

The difference with the Chinese invention is that you don't need to transport the waste to a separate breeder.

[–] echodot@feddit.uk 2 points 4 days ago (1 children)

Isn't a Dyson Sphere supposed to use solar panels? I don't know how you would find enough water to cover the interior of an object with the radius of the Earth

[–] AngryCommieKender@lemmy.world 1 points 3 days ago* (last edited 3 days ago)

It was a joke. We have invented fission and fusion, but the reactors are still attached it to a Rankine Cycle.

Also, the radius would be considerably larger than the sun. Perhaps not encapsulating The Earth, but that seems like a potential death sentence, if we built a Dyson Sphere rather than a Dyson Swarm

[–] eleitl@lemm.ee 1 points 3 days ago

No, we do this in a fusion weapon. Half of its energy output is from fast neutron fission of the uranium tamper.

[–] Geetnerd@lemmy.world 1 points 2 days ago

Cool.

When can I expect my T-45?

[–] dzso@lemmy.world 10 points 4 days ago (1 children)

This seems like a good step on the way to developing the technology necessary to build a fission plant in the future.

[–] echodot@feddit.uk 4 points 4 days ago (2 children)

I'm sure China will share a lot of technological innovations as well

[–] explodicle@sh.itjust.works 1 points 3 days ago

Everybody has been stealing each other's nuclear secrets for decades.

[–] sunzu2@thebrainbin.org 2 points 4 days ago (2 children)

Just like the US "shares" its IP

🤡

B..b..but murica bad!

[–] echodot@feddit.uk 3 points 4 days ago

I don't imagine the US is going to be contributing much to science in the future.