Fusion Power Plants

[Judas Iscariot]

YES... It would...

Jake from the CT-Striker forum found the passage that describes the types of reactions in TU canon...

So, Thank you Jake

 

[TheEngineer]

Hi !

The more I read, the more I like catalyzed cold fusion. A little more handwavium and far less "BUT...".

Yep.
As I said before TL9 is the starter for both fusion and artificial gravity.
Now you really could think of a gravitically catalysed fusion, e.g. by microscopic gravity traps, which would allow much lower temperatures and offer much more control of byproducts and perhaps also much smaller sizes.

@Judas:
If you deal with this topic You might also try to find out another solution for the inefficiency problem of the canonical fusion plants...

Regards,

TE

 

[Merxiless]

I always took the Star Wars stance:

It works, it looks cool the ship needs power and a drive, go with it, who cares how it works, because in the end, its (all fiction / Hasn't been invented yet / Breaks at least two laws of real world physics from the get-go)

In the vein of:
"Blasts off, bound for deep space, with a roar, and twin engines glowing."

Certainly, heretical to some here, but a lot less arguments, in-game.

 

[Straybow]

I just found a blurb in FFS that describes fusion reactions as being D-T or Protium (Unrefined fuel)...

I am writing up a proposed tech solution for this, and unintended technology applications that can be produced as a result.

…Or, in a pinch, ALL water and hydrogen gas contains small amounts of Deuterium. You could force a low-yeild D-D reaction (and have additional "emergency" shielding that can be put in place for just such an ocassion) for a short period of time.. Maybe enough to get .5 of a jump out of the available Deuterium in the "fuel"...

I show in Going Pirate that there is sufficient natural D (0.015%) to account for the power levels of Traveller PP and MD assuming D-D fusion. The H present is essential to the process, otherwise one could buy "super-refined" fuel that lowers fuel requirements by up to a factor of 6600.

Since we can make T from Lithium by neutron bombardment then D-T fusion is also possible with natural hydrogen. It would also yield twice the energy per dT compared with D-D, or rather require only half the hypothetical complete fusion of all D.

Otherwise (as I say in an earlier post in that thread) you need a time-consuming and energy-robbing diffusion processor to isolate D. If you want pure D you'll need 6600 tons of unrefined to get one ton of D. It would take weeks of scooping and refining.

 

[chshrkt]

I always took the Star Wars stance:

It works, it looks cool the ship needs power and a drive, go with it, who cares how it works, because in the end, its (all fiction / Hasn't been invented yet / Breaks at least two laws of real world physics from the get-go)

In the vein of:
"Blasts off, bound for deep space, with a roar, and twin engines glowing."

Certainly, heretical to some here, but a lot less arguments, in-game.

I'm with merxiless on this one.

Has it occured to y'all that perhaps when the fusion reactors were chosen for the game that the GDW folks were not nuclear physicists and just did not know about the RL problems with neutron radiation containment?

 

[Anthony]

I show in Going Pirate that there is sufficient natural D (0.015%) to account for the power levels of Traveller PP and MD assuming D-D fusion. The H present is essential to the process, otherwise one could buy "super-refined" fuel that lowers fuel requirements by up to a factor of 6600.

You can anyway. Since the H is clearly not being burned, just recycle the H and add a new supply of D.

 

[TheEngineer]

You can anyway. Since the H is clearly not being burned, just recycle the H and add a new supply of D.

Yep. Thats the problem.
You somehow have to get rid of the H. Well maybe its really needed as coolant and sent thru an exhaust....

 

[atpollard]

Well maybe its really needed as coolant and sent thru an exhaust....

By 'exhaust', do you mean those two things on the back of most Traveller spacecraft that look very similar to a chemical rocket exhaust.

 

[Scott Martin]

If you're using gravitic containment, that H is likely to get "enriched" to D which gives you the fusion equivalent of a breeder reactor. If you're just uning a big fuel tank as shielding you'll get much the same effect, but your "lining" tanks will need to be made of something "exotic" (like Zircon) that doesn't absorb neutron radiation.

And remember that proton fission chains, even if only 0.1% "efficient" will still yield terajoules per gram of energy, so discussions of "that isn't efficient enough" are really somewhat moot: our problem in the real world is that we can't *harness* that energy, not that we can't generate the energy. Break even for a fusion plant is getting sufficient *work* (as electrical energy) out of the reaction to offset all of the massively energy inefficient processes that we need to do to initiate and maintain the reaction as well as keep the supporting hardware in existence. one tiny change (like a viable high temperature superconductor, or neutron shielding, or gravity control) would change most of the equations on "viability" (and would probably put a lot of hydroelectric dams out of comission)

I can certainly see different TL's having different designs based on limitations of "physics".

The thing that has always bugged me about TNE / T4 power plants is why fission power plants (which by definition are much more energy dense than fusion ones) have significantly lower power outputs per unit volume, especially given the availability of damper technologies (which are the logical candidate for the "step" in fusion plant efficiencies at TL-13)

The "Steps" as I see them (from the old HG power plant sizes)
TL-9: Gravitic containment makes "small" (starship scale fusion power possible
TL-13: Advances in damper technology make powerplants vastly more efficient
TL-15: Magic unobtainium doubles powerplant efficiency (my guess would be a change that is a precursor to antimatter plants becoming feasible)
TL-16: (step in TNE / T4) Antimatter technologies applied to fusion plants make them more efficient (given the materials tech advance at TL-16, my bet would be on "coherent matter" like BCSD used for the containment vessel)

Scott Martin

 

[robject]

Something I'm wondering is how small should fusion+ power plants be allowed to get? I've seen the "17 liter / 16 kg / 10 kW" model; is that too massive for a PGMP-14? (Perhaps the weapon has a lifter module as well, which negates the weight, but you've still got momentum, right?).

 

[atpollard]

Just my opinion, but personal weapons should not be powered from tiny fusion reactors. Reactors should be vehicle size and larger.

 

[Judas Iscariot]

I'm with merxiless on this one.

Has it occured to y'all that perhaps when the fusion reactors were chosen for the game that the GDW folks were not nuclear physicists and just did not know about the RL problems with neutron radiation containment?

OH... HELL yes...

I LONG ago figured out that while Marc Miller (and particularily Frank Chadiwck) could produce a pretty good game (in terms of mechanics and basic assumptions)... That some of the specific assumptions were pretty weak...

Take an argument I had with Frank Chadwick in 1981/82... It was over the size of computers, where he claimed that in order to get a powerful computer, you would always need something "Big" (Not his exact words, there but these were, and that small computers, like the Apple or then relatively new PC, would always be extravagant toys...

I figured then that they might not have a complete grasp of some of the issues they were dealing with...

Of course, they have a much better grasp of many of them than most have.

 

[robject]

Just my opinion, but personal weapons should not be powered from tiny fusion reactors. Reactors should be vehicle size and larger.

I agree. Which is why PGMPs make me worry. I guess in this case it's better to ignore LBB 4 and decide what's reasonable -- perhaps they use cartridges.

 

[Anthony]

PGMPs and FGMPs have lots of problems if you get concerned with realistic physics, so I'd avoid worrying about that particular problem. A bigger problem is that PGMPs and FGMPs have a power consumption that's high enough that the implications of a backpack-sized nuclear generator producing that much power might need closer thought. Changing them to use cartridges (a la TNE) would avoid that problem, but is a pretty big change from the LBBs.

 

[Wol]

PGMPs and FGMPs have lots of problems if you get concerned with realistic physics, so I'd avoid worrying about that particular problem. A bigger problem is that PGMPs and FGMPs have a power consumption that's high enough that the implications of a backpack-sized nuclear generator producing that much power might need closer thought. Changing them to use cartridges (a la TNE) would avoid that problem, but is a pretty big change from the LBBs.

Mind you these are in Power assisted personal battle armour - really they are small nuclear craft...How do they compare with tiny space craft design?

 

[robject]

That's an excellent point, Wol -- Battledress probably does have the smallest fusion power source on the market, and therefore will be able to power PGMPs and FGMPs.

While I love CT, I think this is a candidate for change -- and one that doesn't really seem to hurt CT.

So, then, I see the minimal fusion+ generator being carried in battledress, which allows it to be bulkier than if it were simply a backpack power unit.

That means that the non-BD versions probably use cartridges, a la FFS.

The PGMP-12 holds 40 cartridges (I imagine it could hold more in this revision). Does the PGMP-12, then, still have a battery pack, presumably to power something that the cartridges can't? Something to absorb the recoil?

The PGMP-13 and FGMP-14 run off battledress power supply and have an integral reserve of hydrogen or whatnot for hundreds of shots.

The PGMP-14 and FGMP-15 probably require cartridges like the PGMP-12, but also have a low-power grav belt-like unit to handle the weight (but you still have mass issues). Thus the battery pack powers the weak nullgrav module.

I imagine the FGMP-15 should also have a battledress variant which doesn't require cartridges.

 

[flykiller]

Just my opinion, but personal weapons should not be powered from tiny fusion reactors. Reactors should be vehicle size and larger.

book 5 says that the minimum size power plant is 1 dton. I took this to mean that 1 dton is the minimum size that can run reliably on a continuous basis, and that smaller fusion packs have capacity and time-of-operation limitations - the smaller the pack the less the capacity and time. in effect the fusion packs behave as batteries without the energy storage issues.

'course most players don't care about any "realistic" background justifications. they just want to pull the trigger and get a nice big boom.

 

[Anthony]

That's an excellent point, Wol -- Battledress probably does have the smallest fusion power source on the market, and therefore will be able to power PGMPs and FGMPs.

A suit of battledress probably has a sustained power requirement of less than a kilowatt. An FGMP has a burst power requirement that is likely to exceed a megawatt. You could use the fusion power source for battledress to (gradually) recharge batteries, but there's no way the power output is anywhere near high enough to directly handle the drain of the weapon in a firefight.

 

[robject]

In trying to determine what the minimum F+ size is, I have to find out how much power things use. In my mind, the benchmark for power use in non-vehicles is battle dress.

A suit of battledress probably has a sustained power requirement of less than a kilowatt. An FGMP has a burst power requirement that is likely to exceed a megawatt. You could use the fusion power source for battledress to (gradually) recharge batteries, but there's no way the power output is anywhere near high enough to directly handle the drain of the weapon in a firefight.

The battle dress power requirement seems plausible. The energy requirement for the plasma gun seems prohibitive.

The design sequence in T4's CSC says that battle dress at TL13 requires 50 kW on account of the STR, DEX, and END augmentation. My back-of-the-envelope calculations from FFS2 for the PGMP-13 seems to call for 90 kj per shot, which is perhaps 9 kj per second for charging the weapon up.

FFS1 has example battle dress listed, and they only require from 3 kW to 8 kW.

So if you're saying that FFS2 is incorrect, that's fine by me. Or if you're saying that I did something wrong, that's also fine by me.

It is interesting that Steve Perrin rates the Strength of a character wearing augmented battle dress based on the power of the propulsion system, in a logarithmic curve, with 1 kW mapping to a strength of 2 and 100 kW mapping to a strength of 24.

It seems to be the "correct" way to do such a thing.

 

[Anthony]

The design sequence in T4's CSC says that battle dress at TL13 requires 50 kW on account of the STR, DEX, and END augmentation. My back-of-the-envelope calculations from FFS2 for the PGMP-13 seems to call for 90 kj per shot, which is perhaps 9 kj per second for charging the weapon up.

If you assume that you fire once every ten seconds, sure.

The figure of 50 kW is stupidly high. Something with the same activity level as a human will use about 1W/kg mass on a sustained basis, up to a couple times that on a short term basis (one round). Something insanely fast (double human speed) would use 4-8x as much, depending on some design factors.

It is interesting that Steve Perrin rates the Strength of a character wearing augmented battle dress based on the power of the propulsion system, in a logarithmic curve, with 1 kW mapping to a strength of 2 and 100 kW mapping to a strength of 24.

Aside from being 10-50 (depending on assumptions about what power level means) times too much power at all levels, sure.