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Building an Arcology

Oh, should have redone the total for that greater usage:
250kdT (park, with layer of dirt) + 400kdT (apartments) + 100kdT (utilities) + 50kdT (office space) = 800kdT

Edit: If you up the living space to, say, 10dT per person you get very spacious quarters, and 1MdT of space for a total of 1.4MdT. end edit
 
Fritz, I could agree with your numbers if we're talking about ground-based or beanstalk-based arcologies, which import heavily from a productive mainworld. I am generally coming at the problem from space-based arcologies.

Yah, 1000 dt for "life support" sounds absurdly silly. Wot, a space bigger than a liner to support one person for 80 years? But I am thinking about someone who has to live in the same place for his whole life, and has to breathe the same recycled air too. We're talking space for living, school, vocation, food production, recycling, medical care, recreation, everything required to support "a person".

That's why 1000 dt also seems small. Imagine that your "world" is essentially boiled down to 1000dt. Would you retain your sanity in a box 10t x 10t x 10t? The disconnect is that we play Traveller from our frame of reference, and in fact many of the rules are for our benefit rather than for the TU's benefit (examples: flat sector maps, contragrav and cutlasses). Otherwise we could say "holography solves space issues", but for game purposes, that's the tail wagging the dog.

I assumed Biosphere 2 as the standard, which is supposed to work with a minimum of machinery and 100% recycling. Even so, there's nearly 1000 dtons of air per person in Bio:2!

Perhaps that's TL8, then.

But we know that Manhattan is more than a 82km^2, 3m tall pancake. It could be a ground arcology, and a beanstalk arcology, but all of our cities are heavily dependent on imports, and could never be deep space arcologies.
 
How about edible vat grown algae. The entire project could pay for itself in few decades if there is a market. Ooooo and banks. Belters need credit and bankers do not want to live on asteroids.


Space per person considerations . . .
When we talk about people spending time in an enclosed space think the submarine crews. After a generation or two these people would be agoraphobic in wide open spaces.

The Ultmia Tower has an average of only 1,500 cubic meters per head and is about 107 dtons (?) per person BEFORE agricultural considerations, not a lot of space to be sure but cost is a consideration here. For the colony to work it will have to be able to make money.

Granted Manhattan has lots of open space above roads and between buildings. But air handling and excess heat disposal is “free".

I am thinking that the working class will live in a college dorm type setting. Communal facilities and little privacy because every cubic cm needs to be paid for. Air tax might be charged per cubic cm of residence.

The upper classes will have so space to be sure but it is going to be expensive in the long term.
 
how about just 'building' it using the ship design rules, but no 'engines'? I think I saw extended life support rules somewhere on the web for space arcologies. Just make sure it can support whatever accelerations the G's of the world are. And ignore the size limits of the rules.

just an idea
 
^Yeah but. . . .
Industry, some kind of native food production, recreation for the long term, schools, starport facilities, space for future development, and a lack of heavy weapons make the concerns of a space arcology are different from a starship. HG could be used as base to be sure but if you ever wanted any level of detail you are in a different place. This would also be a base for colonies on airless worlds. Less a FF&S and more of a rule of thumb guide from what I am reading. If X number of people @ TL ? = Y number of people with modifications for industry location etc.

The problem with a space colony in Traveller is that it means that there are simply no good rocks at all in-system that could be used. Gravity wells are child’s play when any commercially available grav vehicle can obtain orbit. Fusion powered thruster tech means no harmful exhaust and beanstalks mean cheap bulk transport. That arcology is gonna be prime real estate wherever it is.
 
A few points to make before going into the economics of orbitals.

1) FF&S-2 has values for "Extended Life Support" from "Vat Grown Algae" to "Yup I like Beef". Before making up your own numbers from whole cloth, take a look at them. they range from 100 to 1,500 m&sup3 per person, with pop minimums of 25 to 75 (more extensive habitats have higher mins)
2) Biosphere 1 was a debacle: please don't use it as a base for anything serious (they flushed the air supply "on the sly" repeatedly, and a crew was insufficient to maintain the internal systems...) Lessons were learned, but it was *not* self contained.
3) if you're "poor" you're probably living in something like a college dorm anyway, If you're rich then you can afford a nicer spread. In Vancouver $2,000,000 either buys you 1,500 square feet near the top of a tower downtown, a slightly run-down home in the "good" part of town across from the ocean / beach, a nice house in one of the "good" parts of town with an ocean view, 4 "average" 3 bedroom houses, a fairly large acherage inland 30-40 minutes from the city, or your own private island in the northern gulf islands. the "choice" between "quality" of habitat or "Quantity" of habitat is already here, most folks just aren't used to thinking that way.
4) You're using the wrong paridigm for habitat construction: you will find that the cost for 2,000 square feet of living space is much greater in a yacht (or cruise liner) than in a house. Yes, the "house" must be pressure tight, but floating houses (we have them here) are generally close to the "square foot" construction costs of "standard" houses (they use more prefab components, but then no-one expects them to be built the same way as "normal" houses)
5) A lot of the cost for current construction is based on the cost to drag it out of the ground, transport it to a refinery (whether this is a sawmill or a smelter) power to refine it and the cost to ship it to the construction site. If you are doing this in orbit (and have fusion rockets) most of your "transportation costs" approach 0, your cost for refinery energy is amortized over *decades* if you are using solar arrays, and your cost to "dig it out of the ground" is minimized if you have planetoud belts. As a result, orbital construction costs (once you have built the infrastructure) will be significantly lower than "planetary" construction costs, even ignoring efficiencies that having ready access to vaccum (without having to pump the air out) gives you.

I think that perhaps too much is being made of the "cost" of these archologies. What is the "cost" of a current home? My house, on a 33x120 lot in sunny (not) British Columbia is currently valued (tax assessment) at over $400K . The "house" value has doubled in the last three years, to a massive $30K, so that 33 x 120 (~ 400 square meter) chunk of dirt is "worth" about Cr100,000. What's the cost of 100 square meters of hull and dirt? One of the reasons that real estate is such a "good investment" is (to steal a line) "because there isn't any more of it being made"

There is *lots* of money to be made in selling the suburban (suborban?) dream, and with a planetary population in the 10's of billions and (relatively) inexpensive orbital / interplanetary transit you're looking at an economic situation where it's probably *cheaper* to buy into an orbital archology than to buy an appartment on planet.

And you can't tell me that those developers who are currently making a killing selling subdivisions of exactly the same cookie-cutter houses can't do the same in space? (they'll probably have the same problems too ;) )

Pro's: Pick your climate, don't be bothered by rain etc
Con's: The relatives get a bit freaked out by having the "ground" hang over them like that (spun habitat)
Pro's: Mother in law won't visit, due to aformentioned Con.
...

If you have a system pop in the 10s of billions and the capability to build archologies (A or B starport) then you have a MINIMUM of tech/9. If you can build starships, you have a min of Tech/11, and if your homeworld sucks in any way, that also increases the base tech (and reduces the effective "cost" of the habitat). This also INCREASES the number of people who would see orbital habitats as an attractive alternative.

If the atmosphere is "tainted" in any way, then you're living in archologies *anyway* and a cylindrical archology will give a lot more space (cubeage) than any ground based habitation, since you're only paying for the surface area (the hull) not the volume enclosed (ok, air will cost a bit, but that's really stretching it...)

Even Robject's "Trade Minimums" are trivial: Archology 1 produces machine parts, and rades with Archology 2 (electronics) Archology 3 (fine art / entertainment) Archology 4, 5 and 6 (Ag, forest products and sushi respectively) while getting materials from Rockball 2 (silicates and corbonates) Daedalus Fuels (gasses) and Belter Consortium 318 (metals and rare earths). For large production runs on energy intensive products, excess power is provided by trading with Solar Farm 226 for beamed power, although their "anchor" client is the bulk smelters owned by Belter Consortium 318.

Most of the infrastructure would be supported by *taxes* just like any other large public works. We just don't have any experience with "the world" being a public work.

No "superfund" sites, since anything really polluting is just packed up and parked in a holding orbit until someone decides there is something in the "junk yard" that can be more economically processed from waste than refined from raw materials.

Chances are you'll be using passive solar for generation, both because it will probably be much lower maintenance than running a reactor, but also because your "air" is probably largely generated by converting silicates into silicon and O&sub2, which leaves you large piles of purified (or partially purified) silicon which has few "construction" applications other than solar cells and other "low quality" electronics ("High tech" electronics will probably use carbon semi-cons: diamond can handle more heat than silicon...)

Anyway, you get the idea, and yes, I will eventually get around to populating the "other deep space facilities" thread...

Scott Martin
 
Duh!

I forgot to point out the single largest assumption that makes Orbital Archologies cost effective:

There's nowhere nearby to move on the cheap.

This is the reason that property prices in Honolulu, New York , Vancouver and San Fransisco are so high, despite the fact that this planet has bajillions of underdeveloped square kilometers, and why prices in "prarie" cities tend to be so much lower than the national average.

As a result, orbital archologies will be severely uncommon unless There are NO nice habitable areas with relatively inexpensive land nearby for the rich folks to "get away" to. Reasons for this could include:
-YTU / the system has no FTL travel capability
-FTL travel is expensive or heavily regulated
-Biohazards are a significant threat
-All of the nearby planets / systems are also insanely overpopulated (Core or Solomani Rim sectors anyone?)

Scott Martin
 
Fritz, I've been thinking that your idea about sharing "public space" is reasonable. With one caveat.

Since the closest thing to a self-contained arcology we have is Biosphere 2 (as I mentioned, it was a failure, but a darn good one), I don't see what alternative I have than to take it as at least one data point (not good enough to draw a line, but it's better than nothing).

Bio2 didn't have any parkland, per se -- everything was (more or less) used to support those 8 people. Every cubic meter was important.

FFS' suggested 100 dt/person is within an order of magnitude of my ever-diminishing requirements. I suppose I could concede down to that itty bitty number.
 
robject, one of the things to realize, though concerning all those "places" you mention is that they are all workspaces and are accounted for in that. Now, I recognize my numbers may be low on the workspaces, so that could be looked at.

Edit: robject sorta concedes this in the post he snuck in there while I was typing... end edit
However, one of the things you are not considering (I think) is redundancy. Not everybody needs a medical facility - at least not at the same time. What percentage of folks will be in that position at any one time? That's why I figured the park for 25% of the population at a time - you are never (yeah, maybe I shouldn't say that word) going to have everyone go to the park at the same time. Not everyone is going to flush their toilets at the same time (though some bunch of kids would try it...
file_28.gif
), or go shopping at the same time. This is especially true since you don't have to worry about day/night cycles nearly as much (you need some for all the plants). Some of the park will see dual use as an orchard, and all of it will see dual use as an air filtration system.

Also, robject, my calculations are not for a resort arcology, but a working man's abode - hence the comparison to Manhattan.

(BTW, no I wouldn't want to live in that space arcology. I want mountains, not the inside of a sphere or cylinder.)
 
Oh, I also didn't take into account fuel for any kind of power system. I think you could do some of it with solar, you might need something more robust if you build it very far out from the primary.

Personally, I would use fusion just so you always have hot water. Navy showers are bad enough, but when they're cold showers... :eek: :(
 
There seems to be some differing opinions on how dense people can live and still feed themselves. So I conjured up a little list of population density (per sq.km) and also what percentage of the population that lives in cities. based on this .

</font>
  • Nation --- Pop. density - Percentage Urban</font>
  • Netherlands -- 392 --- 66.8%</font>
  • Bangladesh -- 985 --- 25.0%</font>
  • Singapore --- 6 333 --- 100%</font>
The Netherlanders are able to feed themselves. I am pretty sure that Bangladeshis can do so too, although on a poorer level, I don’t believe Singaporeans can do it. Therefore, based on this data, I think that at TL 8, 500 dudes/ km² can easily feed themselves and have the space for other activities, like industry, space ports and so forth. 500 dudes/ km² equals 5 dudes/hectare equals 2000m² per dude.

-------------------------
Runo'da'mil Rotating Torus, RRT

Gravity: 0,01G
Rotational speed: 1/hour (1/3600Hz)

a/g = v²/(r·g)
v = 2pi·f·r
=>
a/g = (2pi·f·r)²/(r·g)
=>
a = 4pi²·f²·r
=>
r = a/(4pi²·f²)

r = 0.01/(4pi²·(1/3600)²) = 3283m

Baah! Puny!!

---------------------------
Gnusams Planetary Girdle, GPG
Gravity: 1G
Rotational speed: 1/24h (1/86400Hz)
r = 1/(4pi²·(1/86400)²) = 189 089 646m

GPG be a project for grand-pappy me thinks.

---------------------------
The cross-section of the torus would be a rectangle in this example. The Torus would have inclination of axis towards the sun with, say 20 degrees. Giving it a cross-section width of 2·3283m·sin20 =2246m
The farmland area would then be:

2246·2·pi·3283 = 46329808 m²

enough area for sustaining 23165 dudes.
 
This has some bearing on starports, as well.

I think that Fritz' idea is of a habitat, rather than an actual arcology. Thus, a starport may have a Fritzian habitat (appx 8 dt per person?) to support personnel, plus starship-like volumes for temporary visitors.

Then, an arcology would have a habitat for its personnel... but surely agriculture would be separate from habitat in this case. Agriculture may range in average volume, probably primarily based on tech level. Is "ecosystem" another part, or is that the same as habitat?

Fritz' view minimizes open spaces, relegating them to a proportional recreational area. In other words, food and air production won't need that. At TL12, this may well be the norm. I hate giving up my numbers, but his estimates may be reasonable.
 
Originally posted by Gnusam Netor:
There seems to be some differing opinions on how dense people can live and still feed themselves. So I conjured up a little list of population density (per sq.km) and also what percentage of the population that lives in cities. based on this .

</font>
  • Nation --- Pop. density - Percentage Urban</font>
  • Netherlands -- 392 --- 66.8%</font>
  • Bangladesh -- 985 --- 25.0%</font>
  • Singapore --- 6 333 --- 100%</font>
The Netherlanders are able to feed themselves. I am pretty sure that Bangladeshis can do so too, although on a poorer level, I don’t believe Singaporeans can do it. Therefore, based on this data, I think that at TL 8, 500 dudes/ km² can easily feed themselves and have the space for other activities, like industry, space ports and so forth. 500 dudes/ km² equals 5 dudes/hectare equals 2000m² per dude.

...the big question is "and how high is your ceiling", because in the Netherlands, the ceiling may theoretically be 100km high. So do you pick 1km? 100m? 3m? In other words, how much volume of air does one person's support structure need?

Phrased differently, is the air quality going to be like that of a Scout, a Liner, Regina, Mexico City, Tokkaichi, or something else?

Japan is 300+/km2, China 200+/km2, and neither can feed themselves. Or is that true? Japan might be feeding itself.

Biosphere 2 did show that 40 people could be fed from one hectare.

From your numbers and my musings, I'm thinking the single most important factor for self-sufficiency is going to be government... and secondarily TL.
 
I would like to add, that i first did the calculations based on how much volume an archology-inhabitant would need. I realised though that if we assume that they should grow their stuff "old-school" the growing area is the limiting factor anyway. This RRT space-farm-station would probably be fairly thin with say a 99m air-dome, 1m of soil and say 20m of hull/livingarea/industry.

That would mean that it's displacement would be:

(120·2246)·(2·pi·3283) / 14 = 397MdT

wow that was big... let's hand-wave away the air-dome.

disp.= 69.5 MdT

still pretty big... rats, i'm sure it's expensive too.
 
Good, that means my assumptions were based on old-school, whereas Fritz' assumptions are tech-savvy. He and I have to reconcile.

But I wouldn't worry about the cost. If we used planetoid-tunneling prices, 60 million dtons is only MCr6... and even if it's 10 times the cost, it's still only MCr60... a paltry sum for the centerpiece of a massive arcology.
 
Originally posted by robject:
...the big question is "and how high is your ceiling", because in the Netherlands, the ceiling may theoretically be 100km high. So do you pick 1km? 100m? 3m? In other words, how much volume of air does one person need?
good question, read my previous post

Originally posted by robject:

Japan is 300+/km2, China 200+/km2, and neither can feed themselves. Or is that true? Japan might be feeding itself.
Japan has mountains and China deserts, let's build our archologies without those.

Originally posted by robject:

Biosphere 2 did show that 40 people could be fed from one hectare.
Now thats a number I wish I had earlier!

Thus my RRT can feed:

46329808 / 250 = 185319 dudes
 
Well, yeah, "old-school" farming will be right out - unless you want a planet, and not an arcology.

I think you can grow meat on a significantly smaller scale than cows - how much room do chickens really need? (Not much if the ones we raised to feed the falcons is any indication....) Better yet, rabbits need very little space, and guinea pigs even less........ And, you have to have some way of disposing of your never-fail, unwelcome guests. :D

Edit: I mean rodents, not your mother-in-law!
file_22.gif
end edit
 
So, handwaving slightly, you have 75 million dtons of "life support" for 200,000 people?

About 375 dtons per person.

I can live with that.

Actually, if this is "old school", I'd stay with 1000 dtons per person. In other words, 1000 dtons per person at TL7.

That suggests to me a metric of 7000 / TL, but that's probably not steep enough for Fritz.

Okay then, how about 10,000 / TL^2. Still not enough, eh?

2^(18 - TL)

There. At TL15, "permanent" life support is 8 tons per dude. At TL12, it's 64 tons per dude. At TL7, it's 2048 tons per dude. At TL20, it's 0.25 dtons per dude. Cool beans.

The 375 dt / person ratio would fall somewhere between TL9 and TL10.

I'm happy.

Fritz?
 
Originally posted by robject:
So, handwaving slightly, you have 75 million dtons of "life support" for 200,000 people?

About 375 dtons per person.
i assumed 20m of hull, we could go with 2m too and let the archolgists live in sheds on the surface...
I just calculated how much farming area a torus would yeild, based on how big it would be.
 
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