GURPS Spaceships, upscaling sizes

SRoach · 06-18-2024, 05:41 PM

I agree that it should be possible to produce total life support in a package that is no bigger than whatever is consuming the life support.
UltraTech has a Suitcase Universal Replicator, on page 93, that can produce a quarter pound of material in 10 seconds. Assuming it can do that once per minute without overheating, and extrapolate that up to 24 hours, and you have a production capacity of 360 pounds of production capacity per day. Most of that time could be spent turning atmospheric CO2, and sealed waste containers from the head, into breathable air and "sanitized" feedstock modules for later use, in something that could fit under the galley counter. Or as part of it. That would certainly make for a diet that was more interesting, and desirable, than rotating the same 3 E-Ration flavors for the duration of the journey.

A little digging gave me some ROUGH numbers for CO2 production and O2 consumption for an adult human. It's Something like 1.73lbs of O2 consumed per day, and something higher than that for CO2, (2.2kg, for an active adult, per the EPA's guidelines, with a lot of wiggle room, as one would expect from a government agency). Data is taken from two different websites.
(Personally, I'd take that 2.2kg, divide it by 44 and multiply it by 32, or the molar mass of the O2, with the C cracked off, as that's where the majority of the CO2 is coming from. That gives us an upper bounds of 1.6kgs of O2 consumed.)
Still, (1.6kg+2.2kg)*2.2=8.4lbs, is well within the materials handling capabilities of a suitcase nanofac from Ultratech, (UT92), making the throwaway line on page 17 of Spaceships ("Alternatively, vessels with replicators....can be assumed to be able to manufacture all necessary food.")

It does, however, conflict with the numbers for replicators, found on page 16 of Spaceships under "Factory (TL8) [ANY!]", which not only precludes putting ANY factory on an SM+5 craft, (which is too bad, as that seems like a fine size for a Von Newman probe), but would also limit a roughly 1.5 ton module to about 0.15lbs of output per hour. (Values extrapolated.)

06-18-2024, 05:41 PM	#19
SRoach Join Date: Oct 2015	Re: GURPS Spaceships, upscaling sizes I agree that it should be possible to produce total life support in a package that is no bigger than whatever is consuming the life support. UltraTech has a Suitcase Universal Replicator, on page 93, that can produce a quarter pound of material in 10 seconds. Assuming it can do that once per minute without overheating, and extrapolate that up to 24 hours, and you have a production capacity of 360 pounds of production capacity per day. Most of that time could be spent turning atmospheric CO2, and sealed waste containers from the head, into breathable air and "sanitized" feedstock modules for later use, in something that could fit under the galley counter. Or as part of it. That would certainly make for a diet that was more interesting, and desirable, than rotating the same 3 E-Ration flavors for the duration of the journey. A little digging gave me some ROUGH numbers for CO2 production and O2 consumption for an adult human. It's Something like 1.73lbs of O2 consumed per day, and something higher than that for CO2, (2.2kg, for an active adult, per the EPA's guidelines, with a lot of wiggle room, as one would expect from a government agency). Data is taken from two different websites. (Personally, I'd take that 2.2kg, divide it by 44 and multiply it by 32, or the molar mass of the O2, with the C cracked off, as that's where the majority of the CO2 is coming from. That gives us an upper bounds of 1.6kgs of O2 consumed.) Still, (1.6kg+2.2kg)*2.2=8.4lbs, is well within the materials handling capabilities of a suitcase nanofac from Ultratech, (UT92), making the throwaway line on page 17 of Spaceships ("Alternatively, vessels with replicators....can be assumed to be able to manufacture all necessary food.") It does, however, conflict with the numbers for replicators, found on page 16 of Spaceships under "Factory (TL8) [ANY!]", which not only precludes putting ANY factory on an SM+5 craft, (which is too bad, as that seems like a fine size for a Von Newman probe), but would also limit a roughly 1.5 ton module to about 0.15lbs of output per hour. (Values extrapolated.)