S&P Fusion PPs article

[Vargr]

I really liked the Fusion power plant article on the last Signs & Portents. However, it is lacking a two very important factors so that it is indeed useful on the game.

Namely, the size and cost of the drives at each of the listed TLs. Some pointer to determine the TL of the drive of already-existing ship designs would also have been nice.

 

[BP]

To be honest - I didn't get into this one...

But the only cost I saw was the TL 16 drive (400% of TL 12)

So all costs appear to match the books. Note that HG has price adjustments for lower TL drives bought from higher TL plants (see pg 52 - or the free SRD if you don't have HG). I assume that is the point of the paragraph around TL 15.

It appears existing drives are assumed to be TL 8 unless otherwise noted (matches existing efficiencies).

[These are just my guesses - hopefully the author is on the boards...]

To summarize the article in a table - at higher TLs more weeks of fuel are determined by a multiplier:

 8   9  10  11  12  13  14  15
x1  x2  x3  x4  x6 x12 x25 x38

And TL 16 fuels lasts indefinitely...

The article doesn't answer how much fuel is needed at TL 16 (assume 2 wks extrapolated at 2 tons per rating level...)

I think the design was to accommodate existing designs by just changing the weeks of operation based on TL (not so much to save fuel tonnage).

 

[rje]

I think the design was to accommodate existing designs by just changing the weeks of operation based on TL (not so much to save fuel tonnage).

I think that was very clever of Jame. No design changes necessary. I like that.

 

[Jame Rowe]

I think the design was to accommodate existing designs by just changing the weeks of operation based on TL (not so much to save fuel tonnage).

This was my intent. Speaking as the author, mind.

As for size of power plants by TL ... I hadn't considered that, which is why I hadn't put it in.

 

[BP]

...As for size of power plants by TL ... I hadn't considered that, which is why I hadn't put it in.

HG does have TL tonnage mods already - though a bit 'crude' - on pg 53.

Basically: TL 8-10 +25%; TL 15+ -25%. And a silly 200% cost modifier for TL 15. Funny it states 15+ when the paragraph above the table states 'remains in use until TL15.'

Presumably other tech replaces the fusion power above TL 15 (i.e. anti-matter or something more exotic).

 

[Vargr]

I think the design was to accommodate existing designs by just changing the weeks of operation based on TL (not so much to save fuel tonnage).

This was my intent. Speaking as the author, mind.

As for size of power plants by TL ... I hadn't considered that, which is why I hadn't put it in.

I'm perfectly happy with the designs having the same tonnage. I would just like to have the price list.

 

[Mithras]

Verrry clever. I like those no-change work arounds.

Now fusion powerplants are looking like sensible and solid options at last!

 

[Jame Rowe]

I'm actually thinking I should have made the increases a bit further, like so:

 8   9  10  11  12  13  14  15
x1  x3  x6  x12  x24 x48 x96 x150

but that does seem a bit further from the rules than I thought would be safe at the time.

 

[GypsyComet]

IMHO, the x1 should be at TL12.

 

[phavoc]

This sounds like a clever insert into the rules that doesn't require wholesale changes. Quite clever!

 

[Jame Rowe]

IMHO, the x1 should be at TL12.

It should absolutely not be. The x1 nerfs power plants pretty badly.

 

[GypsyComet]

The default presented in the CRB should be at TL12, the Imperial baseline. Are you presenting a different assumption?

 

[Wil Mireu]

Realistically, a ton of hydrogen fuel should last centuries (effectively indefinitely) for any fusion power plant at any tech level.

Not that realism has been a significant part of Traveller of course...

 

[GypsyComet]

Well yes, but realistically a fusion plant with these sorts of output should parboil the whole ship during that week in jump space. I'll accept more fuel throughput as coolant, as it solves (or mostly solves) both issues.

 

[Wil Mireu]

Well yes, but realistically a fusion plant with these sorts of output should parboil the whole ship during that week in jump space. I'll accept more fuel throughput as coolant, as it solves (or mostly solves) both issues.

Not unless the ship has huge radiator fins it won't... but whatever. As I said, physical realism isn't Traveller's strongpoint.

 

[phavoc]

Well yes, but realistically a fusion plant with these sorts of output should parboil the whole ship during that week in jump space. I'll accept more fuel throughput as coolant, as it solves (or mostly solves) both issues.

Not unless the ship has huge radiator fins it won't... but whatever. As I said, physical realism isn't Traveller's strongpoint.

In all fairness we don't really know the physics of a pocket universe. In theory (ha!) there's no reason why you can't radiate the heat you normally would have out into the universe that's surrounding your ship in jumpspace. The rules are pretty clear that leaving the field (jump bubble in MGT) means being lost forever. So maybe the heat is "lost forever", or just gets radiated into realspace along your jump route?

I can't even recall any rules that even talked about the creation of power from the fusion reactor. If the output is converted to energy, then maybe even the heat itself is converted? Which solves the heatsink problem too.

 

[Wil Mireu]

I can't even recall any rules that even talked about the creation of power from the fusion reactor. If the output is converted to energy, then maybe even the heat itself is converted? Which solves the heatsink problem too.

The energy released is the binding energy of the atoms, in the form of radiation (I think. It's also the kinetic energy of the particles produced too). That radiation can be harnessed using a heat cycle (e.g. to heat fluid that drives turbines that generate electriciy) or by direct conversion (converting the particles' kinetic energy directly into a voltage).

 

[Condottiere]

I guess you could shrink the magnetic bottle, which leaves less place for the fuel, and probably needs less feeding to maintain the fusion reaction.

 

[Jame Rowe]

The default presented in the CRB should be at TL12, the Imperial baseline. Are you presenting a different assumption?

I suppose I already did, based solely on the fact that I took one look at the rules, said "that's not nearly long enough for a starship at any reasonable interstellar tech level," and started thinking.

 

[GypsyComet]

As long as the article is up front about it. I cannot count the number of times Traveller discussions have gone horribly wrong because one (or more!) of the participants was using unstated assumptions that were significantly different from the rules baseline and/or the assumptions put down in the opening statements. These assumptions can and have come from a different reading list of SF from which they draw their Traveller experience, to a variant article in a long-dead magazine, to "that's how we've always done it here" that they can't otherwise source, and that assumes they even recognize what they are doing as different.