You mean apart from the hugely toxic side products that occur from fission and that simply don't exist with fusion?

(Bazongaloid, Thu 18 Oct 2012, 13:41, 2 replies, latest was 13 years ago)

yeah, but I'll take toxic products (which, despite the wailing of hippies, we are pretty adept at dealing with)
over the inherent instability and associated danger of fusion. Well, maybe not take it, but at least accept there are pros and cons.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 13:44, Reply)

*wails*

( tangledupinblue hairy badge with moving eyes, Thu 18 Oct 2012, 13:46, Reply)

A fusion reaction cannot accelerate out of control, you cut off the supply of fuel and the reactions cease
Unlike with a fission reactor, where if you aren't careful with the control rods, you'll wind up burning a radioactive hole through the Earth's crust if it all goes pears.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 13:47, Reply)

I'm pretty sure the "you just cut off the fuel supply and..."
was an argument used in development of fission reactors.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 13:50, Reply)

No it wasn't.
Or if it was, it was an argument made by people who don't understand how fission reactors work and therefore whose opinions are totally invalid.

I don't try and argue against complex brain surgery techniques for exactly the same reason.
(Bazongaloid, Thu 18 Oct 2012, 13:53, Reply)

fission stops if you no longer have enough material to sustain a chain decay reaction.

( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 13:54, Reply)

Why are you talking dirty to me?

(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 13:56, Reply)

because it's science chat and I fancy you.

( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 13:57, Reply)

But that happens a long time after you're dead and charcoally.
with fusion all that happens is it stops and you are left with a big pile of water.
(Bazongaloid, Thu 18 Oct 2012, 13:58, Reply)

I definitely don't know this, so it's just a straight-up question
given the "issue" with fission is that the reaction becomes a chain until it runs out of fuel, and the fusion could do the same, how is fusion safer? I get that you could control the fuel feed in a fusion system which you obviously can't in a fission one because of the whole critical mass thing, but theoretically anything smaller than iron can fuse and release energy. If we build a fucking big one, isn't there a risk assoicated with things other than the fuel fusing? and what if a fuel supply cutoff fails?
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 14:02, Reply)

Fusion doesn't chain reaction in the same way.
You need to keep the pressure and temperature incredibly high to make teh reaction happen. When it does you end up with a net increase in energy, but if it goes tits up and say your reacion chamber broke, there would be an instantaneous drop in pressure. Now there might be a big fire, but the reaction would stop straight away and therfore not continue fusing.

Plus, the product of fusion is helium, so rather than blowing highly radioactive shit everywhere, you have a bit of a fire and everyone talking in squeaky voices. No harm no foul.
(Bazongaloid, Thu 18 Oct 2012, 14:07, Reply)

I totally get the by-products being safer.
assuming it's just and H to He fusion.

I'm still not convinced at large scale there isn't a serious risk - I guess it depends how interchangable temperature and pressure are as reaction conditions.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 14:10, Reply)

There is a risk, it could explode and kill all the people in the factory
but what it won't do, what it physically cannot do, is keep burning and reacting and melting the core so it sinks through the Earth's crust, all the while spewing out deadly toxins and irradiating a wide area around the plant, and some of Wales.

So from that point of view, it's immeasurably safer.
(Bazongaloid, Thu 18 Oct 2012, 14:12, Reply)

You have a similar level of risk...
...if you drop a freshly baked McDonald's apple pie onto the pavement.

They're the hottest substance known to science.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 14:17, Reply)

My labs are only class 2
we can't have McDonalds apple pies in them, the safety handling systems aren't up to it. So I am unable to confirm or deny this.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 14:22, Reply)

I see that.
I just wonder, for a large reactor, just how big a bang it would be. I mean the explosion might well wipe out a whole city rather than just the factory.

Still, I appreciate, better than a massive radiation leak. Unless, of course, it's in Wales.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 14:19, Reply)

The answer is therefore obvious!
We build the fucker in Runcorn.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 14:20, Reply)

Possibly as big as a fission reactor
You wouldn't build it in the city centre, that would be retarded.

You're such a retard.
(Bazongaloid, Thu 18 Oct 2012, 14:20, Reply)

yeah, well, it takes one to know one
and you know perfectly well what I meant.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 14:22, Reply)

That depends which city centre you have in mind.
I can think of a few which would be made more desirable with the addition of an explodey, hydrogen hot-hot thing.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 14:25, Reply)

Erm....you know how a fission reactor works don't you?
Just checking.

Worth reading up on how Chernobyl happened, the control rods became jammed in the atomic pile and thus couldn't moderate the reaction.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 13:53, Reply)

I'm not saying in reality it's physically possibly to stop a fission reaction.
just that theoretically if you remove fuel it'll stop.
( the mighty badger Aphrodite, on a bar stool, by your side, Thu 18 Oct 2012, 13:55, Reply)

Practically speaking, if you stop putting fuel pellets into a fusion reactor
It'll stop right away. A fission reactor remains hot for ages after, not to mention that the fuel itself can become flammable and thus cause further contamination - see Calder Hall for more details.
(Bicycle Repairman "you're also a bit of a wanker", Thu 18 Oct 2012, 13:58, Reply)

If fusion goes wrong it just stops
if fission goes wrong it explodes and you get hot flamy death everywhere.

And I'm not remotely convinced we are in any way "adept" at dealing with nuclear waste. Burying it in a big hole, a hole that they can't dig anywhere because nobody wants it, isn't really dealing with it, it's just pushing it under the carpet.

I'm totally in favour of building a fuck load of new fission plants though, it would make the UK pretty much self reliant. If we did what the french did and just build a standard design several times we'd be creating our own cottage industry too.
(Bazongaloid, Thu 18 Oct 2012, 13:47, Reply)

That instability is not a big issue from my understanding. There's not self sustaining part of a fusion reaction.
It has to be activly managed by magnetic (or laser) compression and removal of the fused products. If you let it carry on it just stops. Nothing like a meltdown.
(PsychoChomp, Thu 18 Oct 2012, 13:47, Reply)

fission curry
fusion not curry
( Naked Ape call me Caitlyn, Thu 18 Oct 2012, 13:45, Reply)

hahahaha!

( sporters I’m sincerely gratitude to you, Thu 18 Oct 2012, 13:52, Reply)

Thanks sporters

( Naked Ape call me Caitlyn, Thu 18 Oct 2012, 13:56, Reply)