Speed of fuel processors at electrolysis?

[allens]

Can fuel processors do electrolysis of water? I believe so, from earlier Traveller material. If so, at what speed? It should be slower than dedicated or combined electrolysis units; this may imply that those (from GT:Starships page 41) need to be sped up.

-Allen

[ak_aramis]

Originally Posted by allens

Can fuel processors do electrolysis of water? I believe so, from earlier Traveller material. If so, at what speed? It should be slower than dedicated or combined electrolysis units; this may imply that those (from GT:Starships page 41) need to be sped up.

-Allen

In Non-GT editions, yes, they can run straight water in....

As for rates... Looking at CT:
Roughly, Traveller TL 8 FPP's can process 20 tons-displacement (Td) of fuel per 8 hours per Td of processor with a minimum FPP size of 10 tons, or 2.5Td fuel per Td FPP per hour... A Traveller TL 15 FPP converts about 8.333Td fuel per Td FPP per hour, and a minimum of 3Td FPP size. (See Bk5.)

[allens]

Originally Posted by ak_aramis

In Non-GT editions, yes, they can run straight water in....

Thanks for the confirmation! Will that produce fuel at the same dtons/hour as for gas giant atmosphere? If so (or, worse, if it'd process that number of dtons of water, since water gives more dtons of hydrogen out than dtons of water in), then the electrolysis units will need to be
sped up - I do hope their speed isn't based on KW necessary for reversing a fuel cell, since otherwise increasing their speed gets you a perpetual motion machine by putting the result into a fuel cell.

Originally Posted by ak_aramis

As for rates... Looking at CT:
Roughly, Traveller TL 8 FPP's can process 20 tons-displacement (Td) of fuel per 8 hours per Td of processor with a minimum FPP size of 10 tons, or 2.5Td fuel per Td FPP per hour... A Traveller TL 15 FPP converts about 8.333Td fuel per Td FPP per hour, and a minimum of 3Td FPP size. (See Bk5.)

The TTL8 rate is 2.5 times that given in GT:Starships for the equivalent GTL8; the TTL15 rate is roughly the same as that given in GT:Starships (8
instead of 8.333). However, GT:Starships has a minimum size of 0.5 dtons at any TL.

I'm wondering because I'm considering a short article on how to optimize ship designs using GT:Starships on ships produced prior to its publication.

Thanks,

-Allen

[ak_aramis]

Originally Posted by allens

Thanks for the confirmation! Will that produce fuel at the same dtons/hour as for gas giant atmosphere? If so (or, worse, if it'd process that number of dtons of water, since water gives more dtons of hydrogen out than dtons of water in), then the electrolysis units will need to be
sped up - I do hope their speed isn't based on KW necessary for reversing a fuel cell, since otherwise increasing their speed gets you a perpetual motion machine by putting the result into a fuel cell.



The TTL8 rate is 2.5 times that given in GT:Starships for the equivalent GTL8; the TTL15 rate is roughly the same as that given in GT:Starships (8
instead of 8.333). However, GT:Starships has a minimum size of 0.5 dtons at any TL.

I'm wondering because I'm considering a short article on how to optimize ship designs using GT:Starships on ships produced prior to its publication.

Thanks,

-Allen

The two TL scales don't mesh up exactly... TTL 15 is roughly GTL12^, and TTL9 is roughly GTL9^, while TTL 8 is closer to GTL9 than GTL8...

Those tonnages are taken by dividing the 1000 tons per unit by the size of the unit, and then dividing by the 8 hours required for the listed rates, using the CT Bk5 High Guard table.

Keep in mind, tho: a ship's power plant is fusion, not fuel cell. A fuel cell can NOT run a cracker without losses. Only reason to do so would be to extract other traces from the source material. Fuelcells generate watts per liter, while fusion generates kilowatts per liter; a FPP requires watts per liter.

[allens]

Originally Posted by ak_aramis

The two TL scales don't mesh up exactly... TTL 15 is roughly GTL12^, and TTL9 is roughly GTL9^, while TTL 8 is closer to GTL9 than GTL8...

I understand your point, but I was actually using 3rd edition TLs, since that's what GT:Starships uses.

Originally Posted by ak_aramis

Keep in mind, tho: a ship's power plant is fusion, not fuel cell. A fuel cell can NOT run a cracker without losses. Only reason to do so would be to extract other traces from the source material. Fuelcells generate watts per liter, while fusion generates kilowatts per liter; a FPP requires watts per liter.

Yes, but if the fuel cell were to give you more watts than used to run the cracker, then one could simply put the fuel cell's output of water back into the cracker. Perpetual energy machine; something to be avoided.

[malloyd]

Originally Posted by allens

Yes, but if the fuel cell were to give you more watts than used to run the cracker, then one could simply put the fuel cell's output of water back into the cracker. Perpetual energy machine; something to be avoided.

Electrolysis of 1 dton/hour of hydrogen from water will require just under 40 megawatts at perfect efficiencies. I'm not sure how big the various game units are, but anything handling 40 megawatts is a going to be fairly big for a portable installation. If TTL8 calls for 2.5 times that (100 MW) out of a dton of equipment.... then yeah, it wouldn't surprise me if the GURPS systems do considerably underperform the Traveller ones, since at some point they were probably based on some piece of real equipment.

For comparison, modern naval reactors generate somewhere between 50 and 500 MW thermal.

[Anthony]

Classic Traveller power plants, at TL 15, were 250 MW/dTon, and consumed 1 ton liquid hydrogen per month per 250 MW. GURPS Traveller power plants are only 40 megawatts per dton, but have insignificant fuel consumption.