Space Station Biosphere

[Ol'Weedy]

I am designing an orbital station, that's sole purpose is to act as an orbital greenhouse/food production center.
I'd planned on just filling it with biosphere tonnage, until I saw the costs in HG; "1 Power point and MCr.2/ton"
I can understand this for a ship traveling the depths of space, were one might spend half their time not even be in a universe that has light. One needs to keep the grow lamps on, and the air circulating.
However, since this will be a station eternally in the sun, the power requirements seem overly steep. As do the monetary costs, when you consider it's pretty much banks and banks of shelves.
I'm thinking of reducing the power requirements by a factor of 10, and halving or quartering the costs for such a station.
Does this sound reasonable, or am I going too far?
I will use a distillation of any comments as my new canon...

 

[AndrewW]

It can replace life support costs, but there is a trade off for that. The initial cost then some tonnage but you save on life support costs needed. Could consider part of that to result in a lower life support power requirement (basic systems).

 

[Arkathan]

I agree with AndrewW.
You are in space. The cost is for life support systems. The biosphere cancels the future charges for life support of crew, tourists and residents. The power is for lighting, air circulation and water pumping, filtration and other recycling needs for both people and the biosphere.

Now, the amount of food produced by the biosphere is geared towards the residents. YOU want to feed a world. I would suggest that instead of a biosphere, aside from the needs of staff and visitors, that you use the Space Station rules for a manufacturing plant on page 67-68 of HG2022.
The Agricultural Plant can be ruled as glass domes with support infrastructure, mapped or drawn in the image of Silent Running or whatever inspiration you see fit.
As you say it is a stellar facing facility, you can offset the need for a huge power plant with solar energy systems found on page 44-45 of HG2022... assuming you don't have to worry about pirates or saboteurs wanting to steal/destroy the panels/coatings.

 

[Ol'Weedy]

I agree with AndrewW.
You are in space. The cost is for life support systems. The biosphere cancels the future charges for life support of crew, tourists and residents. The power is for lighting, air circulation and water pumping, filtration and other recycling needs for both people and the biosphere.

Now, the amount of food produced by the biosphere is geared towards the residents. YOU want to feed a world. I would suggest that instead of a biosphere, aside from the needs of staff and visitors, that you use the Space Station rules for a manufacturing plant on page 67-68 of HG2022.
The Agricultural Plant can be ruled as glass domes with support infrastructure, mapped or drawn in the image of Silent Running or whatever inspiration you see fit.
As you say it is a stellar facing facility, you can offset the need for a huge power plant with solar energy systems found on page 44-45 of HG2022... assuming you don't have to worry about pirates or saboteurs wanting to steal/destroy the panels/coatings.

I agree with him too to an extent, but it is an issue of scale in this case. As partially designed, the current power requirements for the entire 10000dTon station are:
Basic systems: 2000 PP (to keep all the lights on, gravity, ventilation the works).
Maneuver drive: 1000 PP (to keep an entire space station adjust orbit)
Biosphere: 8500 PP (For what? Doesn't need lights, can use photochromic glass to regulate solar intake, ventilation is taken care of by basic systems...cooling?)
The first 2 numbers make sense. 10000dTons doesn't seem that big in Traveller terms, but the ISS (in Traveller size), is about 65 dTons.
The 3rd number makes no sense to me at all (in the specific example above).
Even saving 1KPP by making it spin for gravity, and the fact life support cost is zero, doesn't help. The station is designed to run with barely any crew, and use robots for harvesting.

 

[Ol'Weedy]

I agree with AndrewW.
You are in space. The cost is for life support systems. The biosphere cancels the future charges for life support of crew, tourists and residents. The power is for lighting, air circulation and water pumping, filtration and other recycling needs for both people and the biosphere.

Now, the amount of food produced by the biosphere is geared towards the residents. YOU want to feed a world. I would suggest that instead of a biosphere, aside from the needs of staff and visitors, that you use the Space Station rules for a manufacturing plant on page 67-68 of HG2022.
The Agricultural Plant can be ruled as glass domes with support infrastructure, mapped or drawn in the image of Silent Running or whatever inspiration you see fit.
As you say it is a stellar facing facility, you can offset the need for a huge power plant with solar energy systems found on page 44-45 of HG2022... assuming you don't have to worry about pirates or saboteurs wanting to steal/destroy the panels/coatings.

And...sorry, I didn't read enough of your answer before posting! Nor did I read through the rules from start to finish before starting the design.
Using those rules the power use comes down to a respectable 680PP.
Cheers. And thanks for reading what I didn't!

 

[Arkathan]

No problem.
Rules as written, the Biosphere you describe supplies food air and clean water to 17,000 people.
You said you wanted this as an orbital greenhouse/food production center.
For that, you do not want 8500 tons of biosphere. You want to calculate the tonnage output needed and create that volume of Agricultural manufacturing capability, get your level of crew, divide by two and install THAT amount of biosphere.

 

[Condottiere]

1. I wouldn't try and square this with actual life support costs, because we actually don't know what they actually are.

2. Also, net calculations says paying off monthly costs is cheaper in the medium term.

3. How do I know this? Cheapest possible starship.

4. Energy independence is by solar panelling.

 

[alex_greene]

Rules as written sometimes make no sense, until you realise they're not talking about megajoules and megawatts and real SI units of energy and power, but Energy Points - an abstraction.