Steve Jackson Games - Site Navigation
Home General Info Follow Us Search Illuminator Store Forums What's New Other Games Ogre GURPS Munchkin Our Games: Home

Go Back   Steve Jackson Games Forums > Roleplaying > Transhuman Space

Notices

Reply
 
Thread Tools Display Modes
Old 02-12-2018, 10:22 PM   #51
Johnny1A.2
 
Join Date: Feb 2007
Default Re: Is TS optimistic or pessimistic?

Quote:
Originally Posted by Fred Brackin View Post
I am not at all sure of this. At least in any practical sense.

Deuterium fusion needs heat to initiate but is 4 times as good at making neutrons (80% of the energy of the reaction) as it is heat. You end up having to sustain the reaction with what's left over after the neutrons and then you have to harness the neutrons too.

This is a fundamental characteristic and there is no guarantee that it is solvable.

He3 fusion might not work out either as it is so much more difficult to initiate but if you do get it started you have much more heat for self-sustenance. Or if used for propulsion you have much more in the form of charged particles for handling magnetically.
Yeah, and if you have a decent source of He-3 at hand, once you can use both reactions He-3 wins. But if you have to process megatons of Lunar regolith to get it, or go all the way out to Saturn, then suddenly dealing with the neutrons looks less forbidding in comparison.

As Anthony notes, you can use the neutrons to breed tritium from lithium, but you can also use the neutrons themselves to heat a working fluid. It's a headache from an engineering POV, but by no means unsolvable, and breeding tritium gives you more fuel for a deuterium-tritium reaction.

For that matter, I'm not sure He-3 fusion even beats breeder fission realistically (in terms of the THS canon 'reality') if you have to go to Saturn for your He-3.

Added to that is the prospect of a He-3 cartel. In the THS canon, America has a lot of clout through He-3 control, some other powers are looking to mine Uranus or keep working the thin gruel on the Moon to bypass it. Which is believable if He-3 is irreplaceable.

But when you've got endless oceans full of deuterium, and lithium isn't all that rare, suddenly the comparison looks different.
__________________
HMS Overflow-For conversations off topic here.
Johnny1A.2 is offline   Reply With Quote
Old 02-12-2018, 10:38 PM   #52
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: Is TS optimistic or pessimistic?

Quote:
Originally Posted by Johnny1A.2 View Post
Yeah, and if you have a decent source of He-3 at hand, once you can use both reactions He-3 wins.
D-3He is significantly harder than D-D which is significantly harder than D-T. If you really want neutronless you go p-B11.
__________________
My GURPS site and Blog.
Anthony is online now   Reply With Quote
Old 02-13-2018, 02:24 AM   #53
vicky_molokh
GURPS FAQ Keeper
 
vicky_molokh's Avatar
 
Join Date: Mar 2006
Location: Kyv, Ukraine
Default Re: Is TS optimistic or pessimistic?

Quote:
Originally Posted by Dr. Beckenstein View Post
Well, in the end science fiction is usually a comment on the present, not a prediction of the future.
Usually, sure. But the best is pretty much by definition not the usual. And the best SF is usually an exploration of what the present isn't, of the alternatives, of what society would be like if people had things which they currently can't have and the like.
__________________
Vicky 'Molokh', GURPS FAQ and uFAQ Keeper
Also, GURPS Discord is a nice place for (faster) Q&A and overall GURPS dicussion.
vicky_molokh is offline   Reply With Quote
Old 02-13-2018, 07:44 AM   #54
Fred Brackin
 
Join Date: Aug 2007
Default Re: Is TS optimistic or pessimistic?

Quote:
Originally Posted by Anthony View Post
D-3He is significantly harder than D-D which is significantly harder than D-T. If you really want neutronless you go p-B11.
That one doesn't even produce any gamma rays. I don't know that it'll ever be practical but I don't know that of deuterium-tritium either.
__________________
Fred Brackin
Fred Brackin is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Fnords are Off
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 04:39 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2018, vBulletin Solutions, Inc.