[3e] Stating a Refrigerated Cargo Hold

[GURPS Fox]

So, I was trying to look up refrigerated cargo holds for 3e, and so far, I have found very little.

... just a reference to 4e, where a refrigerated cargo hold is $500 per ton more than a regular cargo hold.

While I plan to have a homebrew fallback option, is there anything for a refrigerated cargo hold?

[Varyon]

Note that "$500 more per ton" for a Spaceships Cargo Hold works out to "$500 per ton," because Spaceships Cargo Holds are free - or, rather, their price is low enough compared to all the other components of a spaceship you can just ignore it. Power draw is presumably similar, low enough you don't need to account for it (just like you don't need to account for the power draw of the computer systems in the Control Room). For volume, the guideline from Payload (B74) is 1 cubic foot per 20 lb cargo space; I believe Spaceships vessels tend to have a density somewhere around that of water, which would instead be around 1 cubic foot per 60 lb cargo space (Spaceships stats assume all cargo holds, fuel tanks, etc are full).

EDIT: Forgot this was about 3e, which I assume means you're using Vehicles. I think the Environmental Control system from page 77 would cover most refrigeration needs.

[RyanW]

Originally Posted by Varyon

Power draw is presumably similar, low enough you don't need to account for it (just like you don't need to account for the power draw of the computer systems in the Control Room).

When you are already dumping reactor heat (thousands of degrees), dumping refrigerator heat (tens of degrees) is a fairly trivial addition.

[The Colonel]

I'm guessing the size of the refrigeration plant is going to make a difference as well - a TL6 reefership is going to have to dedicate significant amounts of machinery space to its plant, but that will fall off over time. I know people use individually temperature controlled shipping containers now, but doubt they have completely superseded the cooled hold. Come to think of it, TL is probably going to have a big effect on the cost isn't it?

Oh, by the way, found this:

http://www.ships-for-sale.com/

when I was down the GoogleHole over this ... did we know about this site? Some of the ships even have deck plans...

[GURPS Fox]

Originally Posted by Varyon

Note that "$500 more per ton" for a Spaceships Cargo Hold works out to "$500 per ton," because Spaceships Cargo Holds are free - or, rather, their price is low enough compared to all the other components of a spaceship you can just ignore it. Power draw is presumably similar, low enough you don't need to account for it (just like you don't need to account for the power draw of the computer systems in the Control Room). For volume, the guideline from Payload (B74) is 1 cubic foot per 20 lb cargo space; I believe Spaceships vessels tend to have a density somewhere around that of water, which would instead be around 1 cubic foot per 60 lb cargo space (Spaceships stats assume all cargo holds, fuel tanks, etc are full).

EDIT: Forgot this was about 3e, which I assume means you're using Vehicles. I think the Environmental Control system from page 77 would cover most refrigeration needs.

So use a combination of additional cost (and I've seen a reference to additional space) and use a modified version of the Enviro-Con energy consumption rules?

Originally Posted by RyanW

When you are already dumping reactor heat (thousands of degrees), dumping refrigerator heat (tens of degrees) is a fairly trivial addition.

True.

Originally Posted by The Colonel

I'm guessing the size of the refrigeration plant is going to make a difference as well - a TL6 reefership is going to have to dedicate significant amounts of machinery space to its plant, but that will fall off over time. I know people use individually temperature controlled shipping containers now, but doubt they have completely superseded the cooled hold. Come to think of it, TL is probably going to have a big effect on the cost isn't it?

Oh, by the way, found this:

http://www.ships-for-sale.com/

when I was down the GoogleHole over this ... did we know about this site? Some of the ships even have deck plans...

Interesting information... could help quite a bit.

[Anthony]

There's two reasons a refrigerated hold would be preferable to individually refrigerated containers:

1. The weight and cost of a refrigeration system should vary with the surface area of the container (roughly 2/3 power of volume), not the volume -- both insulation weight and the amount of heat leaking through (which determines required refrigeration power) are surface effects.
2. A refrigeration system produces waste heat that has to be dealt with. For something built into the ship, you just run ventilation from the inside to the outside of the ship. For containers, they either dump the heat into the interior of the hold, or they need specialized hookups to the ship's ventilation system so they can dump heat outside.

However, as far as Vehicles goes, given that Vehicles doesn't use different tank types for water and liquid hydrogen, I expect this is below the threshold of caring.