Is fusion sh.t?

Get your science fix here: research, quackery, activism and all the rest
Post Reply
User avatar
Grumble
Catbabel
Posts: 830
Joined: Mon Nov 11, 2019 1:03 pm

Is fusion sh.t?

Post by Grumble » Tue Jul 21, 2020 9:52 pm

Slightly provocative title perhaps, but as a science nerd (and occasional scientist) I’ve always been told how wonderful a fusion powered world would be. However, this is a sceptical look at fusion power and it’s made me stop and think.

https://beyondnuclearinternational.org/ ... confusion/
I could squeeze my lemon till my blues went away, if I had possession over pancake day

User avatar
dyqik
After Pie
Posts: 2063
Joined: Wed Sep 25, 2019 4:19 pm
Location: Masshole
Contact:

Re: Is fusion sh.t?

Post by dyqik » Wed Jul 22, 2020 12:18 am

Depends very much in how long the reactors last for before they have to be scrapped.

You can't beat the power density with anything renewable, but the lifetime cost and waste depends on how long the lifetime of the equipment is. IIRC, if the reactor doesn't last for ~30 years, it's not worth building.

User avatar
Gfamily
Dorkwood
Posts: 1526
Joined: Mon Nov 11, 2019 1:00 pm

Re: Is fusion sh.t?

Post by Gfamily » Wed Jul 22, 2020 7:42 am

In terms of power density it's worth noting that the power density of the core of the Sun is less than you'd get in a well run compost heap.
The challenge of fusion is to do orders of magnitude better than the Sun.
My avatar was a scientific result that was later found to be 'mistaken' - I rarely claim to be 100% correct
ETA 5/8/20: I've been advised that the result was correct, it was the initial interpretation that needed to be withdrawn
Meta? I'd say so!

Lew Dolby
Clardic Fug
Posts: 173
Joined: Mon Nov 11, 2019 12:59 pm
Location: Shropshire - Welsh Borders

Re: Is fusion sh.t?

Post by Lew Dolby » Wed Jul 22, 2020 8:21 am

My compost heap could go supernove !!11! :shock:

User avatar
bjn
Snowbonk
Posts: 563
Joined: Wed Sep 25, 2019 4:58 pm

Re: Is fusion sh.t?

Post by bjn » Wed Jul 22, 2020 8:27 am

I hadn’t cottoned onto the nuclear weapons proliferation aspects of fusion reactors, but I’ve previously heard most of the other issues he raised.

I don’t get the power density argument (usually used as a counter to renewables), given the amount of land happily used world wide for bio fuels. (Which are fricken stupid.)

User avatar
Gfamily
Dorkwood
Posts: 1526
Joined: Mon Nov 11, 2019 1:00 pm

Re: Is fusion sh.t?

Post by Gfamily » Wed Jul 22, 2020 9:31 am

Lew Dolby wrote:
Wed Jul 22, 2020 8:21 am
My compost heap could go supernove !!11! :shock:
Unfortunately not - but if it was the size of the Sun it would make that corner of the garden mostly unusable.
My avatar was a scientific result that was later found to be 'mistaken' - I rarely claim to be 100% correct
ETA 5/8/20: I've been advised that the result was correct, it was the initial interpretation that needed to be withdrawn
Meta? I'd say so!

User avatar
shpalman
Dorkwood
Posts: 1583
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond

Re: Is fusion sh.t?

Post by shpalman » Wed Jul 22, 2020 10:18 am

Lew Dolby wrote:
Wed Jul 22, 2020 8:21 am
My compost heap could go supernove !!11! :shock:
Not even our sun would go supernova.
molto tricky

User avatar
dyqik
After Pie
Posts: 2063
Joined: Wed Sep 25, 2019 4:19 pm
Location: Masshole
Contact:

Re: Is fusion sh.t?

Post by dyqik » Wed Jul 22, 2020 4:46 pm

bjn wrote:
Wed Jul 22, 2020 8:27 am
I hadn’t cottoned onto the nuclear weapons proliferation aspects of fusion reactors, but I’ve previously heard most of the other issues he raised.

I don’t get the power density argument (usually used as a counter to renewables), given the amount of land happily used world wide for bio fuels. (Which are fricken stupid.)
It's not the strongest driving factor, but it does make a difference in certain economic cases.

User avatar
Bird on a Fire
Stummy Beige
Posts: 2986
Joined: Fri Oct 11, 2019 5:05 pm
Location: nadir of brie

Re: Is fusion sh.t?

Post by Bird on a Fire » Wed Jul 22, 2020 5:46 pm

shpalman wrote:
Wed Jul 22, 2020 10:18 am
Lew Dolby wrote:
Wed Jul 22, 2020 8:21 am
My compost heap could go supernove !!11! :shock:
Not even our sun would go supernova.
Probably needs more browns.
Born at 356.32 ppm CO2

User avatar
dyqik
After Pie
Posts: 2063
Joined: Wed Sep 25, 2019 4:19 pm
Location: Masshole
Contact:

Re: Is fusion sh.t?

Post by dyqik » Thu Jul 23, 2020 1:23 am

Bird on a Fire wrote:
Wed Jul 22, 2020 5:46 pm
shpalman wrote:
Wed Jul 22, 2020 10:18 am
Lew Dolby wrote:
Wed Jul 22, 2020 8:21 am
My compost heap could go supernove !!11! :shock:
Not even our sun would go supernova.
Probably needs more browns.
It just needs more.

User avatar
jimbob
Dorkwood
Posts: 1203
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Is fusion sh.t?

Post by jimbob » Thu Jul 23, 2020 5:54 am

dyqik wrote:
Wed Jul 22, 2020 12:18 am
Depends very much in how long the reactors last for before they have to be scrapped.

You can't beat the power density with anything renewable, but the lifetime cost and waste depends on how long the lifetime of the equipment is. IIRC, if the reactor doesn't last for ~30 years, it's not worth building.
I'm quoting myself in the ISF as I think the link to the 2013 IET article has now been broken.
jimbob wrote:And on the prospects for nuclear fusion - the IET (former IEE) magazine had an article on this recently

The thrust of the article is that achieving break-even is the easy part - once that happens, the real engineering challenges will have to be solved...
“We could actually build a reactor now, but it would not be economic because whilst the neutrons give up their energy and produce the heat we need to generate steam, they also damage the materials we have available now. The physics of fusion is now well mostly understood and resolved, but what is not resolved is the engineering consequences of generating these neutrons.

“You could build a reactor now with today's materials, but it wouldn't be economic because you would have to build a new reactor or remove and replace to core of the machine within two years. This includes everything inside the plasma chamber; ten billions dollar’s worth of plant.
Have you considered stupidity as an explanation

User avatar
JQH
Catbabel
Posts: 784
Joined: Mon Nov 11, 2019 3:30 pm
Location: Sar Flandan

Re: Is fusion sh.t?

Post by JQH » Thu Jul 23, 2020 3:46 pm

That would be a "yes" then.
And remember that if you botch the exit, the carnival of reaction may be coming to a town near you.

Fintan O'Toole

User avatar
Grumble
Catbabel
Posts: 830
Joined: Mon Nov 11, 2019 1:03 pm

Re: Is fusion sh.t?

Post by Grumble » Thu Jul 23, 2020 3:56 pm

I do wonder if the stellerator will overcome some of these problems - especially the parasitic energy demand presumably the core problem of almost all the energy being ejected as neutrons is the same as for tokamaks though
I could squeeze my lemon till my blues went away, if I had possession over pancake day

User avatar
Martin_B
Snowbonk
Posts: 472
Joined: Mon Nov 11, 2019 1:20 pm
Location: Perth, WA

Re: Is fusion sh.t?

Post by Martin_B » Fri Jul 24, 2020 12:07 am

JQH wrote:
Thu Jul 23, 2020 3:46 pm
That would be a "yes" then.
So an exemption to Betteridge's Law?
"Don't tell me that the sky's the limit when there are footprints on the moon"

Post Reply