Feeding a High Population, Non-Agricultural world

[mavikfelna]

I also have a real problem with this number. Since a biosphere can produce 2 persons life support requirements for 1DTon, you only need to provision the 1 point of power in less than the remaining 89.5 tons to make this figure illogical. That isn't much and a TL8 society has access to fusion plants. You arguably won't even need 1 power if your biosphere could take advantage of natural light or heat from raw solar (which a biosphere in a ship cannot). If you have raw solar then solar panels can also cover off all your other power requirements.

Conventional cultivation produces in the order of 2-4000 calories per meter (per growing cycle). At 14 cubic meters per DTon and assuming a 0.5m vertical space requirement (root tip to stem tip) that means each DTon could produce enough calories for over 50 person days. With future crops I could see that reasonably doubling (given the normal suggestion is 4 acres per family in medieval times and we have dramatically improved yields in one millennia).

Even when we talk about a planet with 0% hydrosphere, that still may not mean zero water anywhere, it just means no large bodies of free standing water. If it is high population it must have water locked up somewhere (even if you only count the population who are themselves around 60-70% water). Recycling water is not that difficult and need not take up that much space, A bucket with a polythene cover is enough, the per capita requirement is quite low when economy of scale is taken into account.

Water in greenhouses can easily be self purifying as you can feed with waste water and collect clean water as condensate that is a by product of transpiration. A greenhouse is not particularly advanced crop farming.

So 90 dTons is about a 3rd of an acre, 1260 square meters. So you're feeding 3 per acre using an intensive farming approach that doesn't use fusion power, just sun, air and water. That's better than the medieval times. And you're producing 365 person days of food per 90 dTons per year. It's no where near biosphere in space, .5 tons vs 90 tons per person per day, but you are saving on power and fuel and the cost difference is 200k per ton vs 20 per ton. Now, the biosphere doesn't need a processing plant or workers to harvest it so that does drive up the cost of the farming method but even if it doubles it, that's only 40 cr per ton. Also, TL7 vs TL12 for the biosphere

Also, solar panels are ridiculously expensive per power point compared to fusion. Fusion is .075 tons per power point and costs 133,333 cr per 2 points, solar is .5 tons per power point and cost 400k cr per 2 points. At TL12 for both.

Ok, running some designs, 1 mega ton pod. Farming method supports 8000 people and cost 7333 per person per month. Biosphere supports 1.2 million people at 579 per person per month. So, even with it's vastly larger power requirement, it's just too good per ton not to use Biospheres. I have to say, that surprized me. This is using TL12 fusion power. The transport requirements for that food is 24 tons for the 8000 and 3600 for the 1.2 million. But you can presumably leave the pod on a planet surface so the transport could be done by grav craft or rail without much difficulty. I am using a planetoid hull though so that may preclude landing but just says it's in-situ building on the planet.

 

[swordtart]

The numbers don't even support Common Consumables being that expensive. On a non-agricultural, high population world you are still only adding a modifier of +1 to the sale price. That normally adds around 10% (assuming a roll in the middle of the range).

The worst case scenario is an airless rock ball where you apply the highest possibly modifier. That comes to +5 and that might swing the price more substantially (25% or more). You can definitely make a profit shipping those to in system colonies and you might even be able to make a reasonable profit shipping to an asteroid main world, but you probably need to be buying cheap from an Ag world as well if you want to guarantee a profit.

The trade tables have been constructed such that other than the asteroid edge condition no world is that desperate for food that it commands a high price as an import. Now clearly they can free up time from producing food from sub optimal sources by importing it instead and use that time to produce more valuable goods that they can export. That is the basic economics of trade, both sides focus on what they do best and share the benefit of the surplus (the art of the deal is in the equity of that benefit sharing).

My rule of thumb is that the big boys are operating at the midpoint of the modified table (11 not including trade codes). They negotiate deals years in advance and lock in steady profits (and that is what sets the midpoint of the modified price scale). That means the normal going rate for a Dton of Common Consumables on a non agricultural world is floating at Cr525. The normal purchase price for a DTon of Common Consumables on an Ag world is is Cr350 giving a margin of Cr175. That won't cover the opportunity cost of a DTon of freight and so at first sight doesn't seem profitable, and it probably isn't for a tramp freighter but that assumes you can source a freighters worth of someone else's freight.

In reality the spot freight market isn't large enough to fill a corporate freighter and so the opportunity cost is actually the profit from some other goods that the corporation produces (and for any specific route only for goods you can sell to that planet). A junior corporate executive might say that you should sell them Textiles instead since the margin is higher at both ends for the same run. At this point the more experience exec would say to look at the name of the goods and think on the words. Common - everyone is buying them. Consumable - they are buying them week on week. You are probably spending as much on food every week as you would on textiles every few months. You will therefore stack your ship with a variety of products in proportion to your ability to sell and those products will generate different profit levels, but the main thing is to ensure a full ship on each leg of the round trip week on week.

For a corporate freighter you are also interested in the profitability of the whole route. You do not want to be shipping credits one way and a world doesn't want to be just buying or you end up with a trade deficit (and you cannot fix this with Tariffs whatever the president of the galaxy might tell you). To get the best deal on that High Population world's valuable exports you need to help them make them more efficiently and if that means you have only marginal profit on one leg then so be it, you will make it up on the other. You might also want to ensure you dominate their Common Consumables market to ensure that no-one else can, that may mean you run it as a loss leader.

If you try to gouge the world, they will either go with someone else who doesn't or their economy will shift to allow them to become more self-sufficient.

Bottom line, even if you feed your population entirely on imports you won't be paying 1500 per ton for them. A million tons of foodstuff should be costing the importer MCr525 so maybe Cr2 per person day. This will cost the wholesaler 4Cr, the retailer Cr8 and the consumer Cr16 (or Cr32 if they eat out). Each stage is making a 5-10% profit the rest of the price doubling is to cover costs (labour, rent, taxes etc.).

 

[swordtart]

So 90 dTons is about a 3rd of an acre, 1260 square meters. So you're feeding 3 per acre using an intensive farming approach that doesn't use fusion power, just sun, air and water. That's better than the medieval times. And you're producing 365 person days of food per 90 dTons per year.

I think we are talking at cross purposes. I was talking about the normal non-agricultural WORLD rather than a spaceship. DTon is only relevant where you need to consider a volume limited environment. The majority of non-agricultural worlds might have sub optimal atmospheres, but even on worlds with hostile environments the people will need to be in domes (or underground structures) anyway so adding head space is simply a matter of a bit more excavation or construction.

I also think that 1m headspace is generous for "high intensity" farming. I have seen numbers down as low as 0.17 of an acre per person with everything tuned ideally with current crops. If you have a meat based diet it all increases significantly but that is a just our current fashion, we may all be printing meat from chemical soups made from chaff in the future.

I stand by the 2-4000 calories per metre figure with modern crops as that seems to be a common value from government agencies (though jackfruit is much higher) and so that means.

It's no where near biosphere in space, .5 tons vs 90 tons per person per day, but you are saving on power and fuel and the cost difference is 200k per ton vs 20 per ton. Now, the biosphere doesn't need a processing plant or workers to harvest it so that does drive up the cost of the farming method but even if it doubles it, that's only 40 cr per ton. Also, TL7 vs TL12 for the biosphere

Also, solar panels are ridiculously expensive per power point compared to fusion. Fusion is .075 tons per power point and costs 133,333 cr per 2 points, solar is .5 tons per power point and cost 400k cr per 2 points. At TL12 for both.

The capital cost is largely irrelevant since this is a worlds primary food source (and we are probably not paying retail costs). All we need is .5 power per person for the biosphere. 1 Dton of TL8 fusion plant can supply 10 biospheres (20 people). It costs 0.5Mcr but since we are not bothered about the footprint on the planet we could tune that down by buying overly large units. I would also contest that since it is not sitting the cold vacuum of space it probably doesn't need the full 1 power. It produces oxygen as a by product. The power requirement for the biosphere is a small percentage of the power requirement we'll need for the rest of the colony. The ongoing maintenance and fuel costs will be minor as well.

If we are talking a planetary installation, the costs of Solar will be far lower (compare costs in the CSC). Solar panels on spaceships are not the same at all.

Ok, running some designs, 1 mega ton pod. Farming method supports 8000 people and cost 7333 per person per month. Biosphere supports 1.2 million people at 579 per person per month. So, even with it's vastly larger power requirement, it's just too good per ton not to use Biospheres. I have to say, that surprized me. This is using TL12 fusion power. The transport requirements for that food is 24 tons for the 8000 and 3600 for the 1.2 million. But you can presumably leave the pod on a planet surface so the transport could be done by grav craft or rail without much difficulty. I am using a planetoid hull though so that may preclude landing but just says it's in-situ building on the planet.

As you say, anything you can do with a spaceship in orbit can be done with a spaceship landed on the planet. If you never intend for that "spaceship" to take off you can forgo a lot of the contents (manoeuvre drive for starters and thence the cost for supporting them). To hollow out an asteroid in space you need space worthy equipment and a means to get it into space, support it etc. To "hollow out" the planet you just need atmosphere protected excavators. As a result you can probably discount even the Cr4000 per DTon hull cost.

The cost of an excavator bot capable of shifting an impressive amount of material per day is surprisingly low. With an OMCR at MCr1 your materials cost becomes zero and the only cost is power for the bot (plus maintenance if your game includes that aspect).

 

[Condottiere]

Has anyone tried just dumping some dirt in a cargo hold, and adding fertilizer, light, and water, as needed?

 

[Galadrion]

Has anyone tried just dumping some dirt in a cargo hold, and adding fertilizer, light, and water, as needed?

It could be done short-term, but drainage (among other things) will quickly become a problem. Longer term, crop rotation will become an issue, unless you completely strip the spent dirt out and replace the entire ecosphere periodically - say, every five growing cycles, tops.

 

[Condottiere]

Layer the floor with some perforated plastic foundation, complete with drainage pipes.

Add an agricultural college graduate to the crew.

The issues we'd have would be calculating added oxygen cleansing, crop yields, energy costs, fertilizer costs, water usage, for a given tonne.

And, of course, how much headroom.

 

[Fluffy Bunny Feet]

Has anyone tried just dumping some dirt in a cargo hold, and adding fertilizer, light, and water, as needed?

Inefficient use of volume and what is your CO2 source? A normal size crew wouldn't be enough. If it was this easy you would use a much cheaper building on site and get your CO2 from the planetary inhabitants.

 

[Condottiere]

We could adjust the day night cycle in the cargo hold, to police oxygen carbon dioxide ratios.

 

[mavikfelna]

We could adjust the day night cycle in the cargo hold, to police oxygen carbon dioxide ratios.

Cargo hold with dirt is basically the 90 dTon figure I gave at the beginning. You still need something tending it and then processing the raw output. For the 1260 cubic meters of space, you need 25.2 man hours of labor per day to harvest food for 1 person. A robot with large agriculture equipment will harvest it in 2.26 hours. A 200 ton agricultural plant will process 10 tons of edible food stuff per day. If we assume a 50% loss rate from processing that means 20 tons of input. Each 90 dTon plot then is producing a measly 6 kilograms of food a day. So the processing plant supports 3333 plots and feeds that many people. Each plant needs 21 workers plus some admins, mechanics and engineers. It adds up fast.
Compare that to a Biosphere that takes 1 ton, 1 power, no crew and produces 6 kg of food that needs no processing, air and purified water.

 

[Terry Mixon]

Cargo hold with dirt is basically the 90 dTon figure I gave at the beginning. You still need something tending it and then processing the raw output. For the 1260 cubic meters of space, you need 25.2 man hours of labor per day to harvest food for 1 person. A robot with large agriculture equipment will harvest it in 2.26 hours. A 200 ton agricultural plant will process 10 tons of edible food stuff per day. If we assume a 50% loss rate from processing that means 20 tons of input. Each 90 dTon plot then is producing a measly 6 kilograms of food a day. So the processing plant supports 3333 plots and feeds that many people. Each plant needs 21 workers plus some admins, mechanics and engineers. It adds up fast.
Compare that to a Biosphere that takes 1 ton, 1 power, no crew and produces 6 kg of food that needs no processing, air and purified water.

Robots! That's what you need!

 

[Condottiere]

Half a tonne of biosphere covers the current life support costs of one human, at a hundred kilostarbux and half a power point.

There are actually three points to cover.

How much space do you need in the (free) cargo hold for plant life to create enough oxygen for one human?

What's the operating cost thereof?

How much food, as a byproduct, would this area produce over a given time period?

Personally, I think oxygen creation is more important, since we can always take along a couple of six packs of instant ramen.

 

[rinku]

Since the question revolved around planets, starship equipment based answers are almost certainly misleading.

Even a rockball has space and sunlight for some kind of greenhouse arrangement to be built, that can likely be set up much cheaper than a shipboard equivalent.

Long terms planetary solutions are also going to be as closed cycle as possible. You ideally shouldn't need to ADD oxygen (although turning rock into O2 isn't impossible by any means), you'd be setting up the usual animal/plant exchanges. With the people being the main animals.

Waste goes into processing, grows plants, plants take in CO2 and release O2. Ideally using direct sunlight if possible, but if needs be you could use artificial lighting powered from fusion, fission, solar or whatever.

 

[Condottiere]

Giant mirrors in space.

And, I recall, deep valleys, though I would think they'd be carbon dioxide traps.

Or, was it monoxide?

Plus, canals.

 

[rinku]

Clearly more than 30% hydrographics...

 

[swordtart]

Since the question revolved around planets, starship equipment based answers are almost certainly misleading.

Whilst that is true, we don't have much else to go on in Traveller terms.

Even a rockball has space and sunlight for some kind of greenhouse arrangement to be built, that can likely be set up much cheaper than a shipboard equivalent.

It depends on whether the planet is in the habitable zone. Many asteroid bases may not benefit greatly from sunlight and will be reliant on artificial lighting. Space might also be an issue if the surface is subject to scarifying clouds of dust, or harmful radiation due to the lack of atmosphere. Not all solar radiation is the helpful kind. I agree entirely though that the cost could be lower and that given space is less of an issue than a ship as you just need to dig for a bit longer.

Long terms planetary solutions are also going to be as closed cycle as possible. You ideally shouldn't need to ADD oxygen (although turning rock into O2 isn't impossible by any means), you'd be setting up the usual animal/plant exchanges. With the people being the main animals.

Yes, and of course there are more exotic mechanisms that we don't current possess the technology for. Portable Fusion Reactors operate off water and produce oxygen as a by product. Humans do not tends to break down water but simply use it as a transport fluid, so recycling it is straight forward. Nanotech could efficiently crack CO2 and I am sure there are other technologies on the cusp of similar.

Waste goes into processing, grows plants, plants take in CO2 and release O2. Ideally using direct sunlight if possible, but if needs be you could use artificial lighting powered from fusion, fission, solar or whatever.

I think this is what a Biosphere is doing. Paying the same cost for them as a private individual would be appropriate. If you were a planetary government on the other hand, you would probably be building from raw materials and therefore your prices are going to be at Fabricator rates (and likely the mid range for those as you are buying in bulk). If you re using nanos many of those raw materials will be converted from the planetary surface and you are just paying for the nanos themselves (and the hive queen will be fabricating those nanos on the fly at reduced cost.
Just because your end point is TL8 it doesn't mean your initial build can't use a higher TL.

 

[ottarrus]

Back to the OP on this one.
Life support, or rather the mathematics of life support are one of the few magical handwaves in Traveller. There isn't one Traveller starship, for example, that has a sewage tank or an oxygen scrubber accounted for in the ship design worksheet. Okay, there's ONE... back in the days of the LBBs you had to install a 1-ton 'improved air filtration system' in your Type S or your ship would smell like the inside of boot with a rotten foot in it. And that 1 ton took up one third of the 3 tons of cargo space you had.
So, getting to your main question, it is germane to note that every Hi-Pop world is also Non-Agricultural. Billions of people take up lots of room needed to produce wheat, rice, and soybeans. It's also reasonable to note that even with a trade system as detailed as the Imperium's, it is virtually impossible to feed billions of sophonts strictly from interstellar trade. That kind of thing is more a Warhammer 40K than Traveller.
So how DOES a Hi-Pop world feed itself? Some suggestions from past discussions:
- Ultra Green power and life support systems... EVERYTHING/ONE gets recycled, vertical gardening, hydroponics, carniculture vats, the whole list of near-future sci-fi solutions;
- Using the space provided by a rockball world in the system to set up agriculture stations where VAST amounts of foods are produced. Imagine landing on Mars and seeing agriculture domes as far as the eye could see. Water is provided by both the Martian ice-cap and by asteroid ice mining and, of course, water is intensively recycled. Would this be expensive? Absolutely, but it's still a Hell of a lot cheaper than having to fly million-ton bulk grain carriers in every single day;
- Maybe the Imperium has found some technology that seriously helps the matter. There's a lot of ground to cover in 7 levels between TL 8 and TL 15. We can't even conceive of the basic scientific underpinnings of TL 11 yet... it's like trying to describe radio to a Neanderthal.
- Lastly, you can just accept that something does the job and just move the story along without worrying about it.

 

[Condottiere]

Life support could be broken down, for humans, to:

1. Climate control

2. Oxygen regeneration

3. Water

4. Food


Earth is large enough, that we have critical masses of everything, and if we didn't like a particular climate or environment, we used to be able to move to somewhere where we did.

Any place in space that we intend to set up our tent is going to need access to the above, and if we're smart, secure long term, if not permanent access.

Which, supposedly, is the role of government.

Besides, providing security preventing others taking what we decided is ours.

 

[paltrysum]

A little technology can make any star system completely functional at producing its own food. Artificial habitats, designed to support biological sophonts, can be considerably superior to any garden world. With a lower population digit, our Terra would be a garden world, yet it is has made 99.9% of all species created extinct. Artificial can be better.

 

[swordtart]

With a lower population digit, our Terra would be a garden world, yet it is has made 99.9% of all species created extinct.

And arguably the wrong 99.9%

 

[Condottiere]

If God wanted them to survive, they would have.