Today we will be looking at Arcologies, a sort of mix of skyscraper and self-sufficient habitat. And will be exploring this idea, where it came from, and what it implies for human civilization. The first thing to understand is that Arcology has essentially developed two different meanings. The original one, where the name derived from, was essentially the idea of self-contained ecologically sustainable communities.

The word Arcology is a portmanteau of the words Architecture and Ecology and that accurately describes the original intent. In this context there’s no special implication of it being a single giant building, though it wasn’t unusual for it be a community under a dome, or linked together. There’s no need for such communities to be isolated from trade but the assumption is they are designed to be at least minimally self-sufficient in terms of things like food, in contrast to a classic cities or castles that certainly didn’t grow their own food on site.

The concept of a single massive building is the more modern notion, and as best as I can tell the enormous skyscraper approach was popularized by the classic game SimCity 2000. This portrayal almost inevitably shows the tower back-dropped against a major metropolis where it is being contrasted against it by its sheer size and usually a lot of plants and greenery in evidence, though it tends to imply that if that greenery is the real food source for the inhabitants the artist has wildly inaccurate notions of how much space growing foods takes.

Traditionally an acre could feed a single person, though just barely, but modern farming does about an order of magnitude better, and climate controlled greenhouses doing hydroponics especially if you can do layered setups supplemented with red light, which is the primary one used for photosynthesis, can bump that up another order of magnitude. So it is actually conceivable to grow enough food for one person on the equivalent space of one large apartment or the basement of a house. But most apartments of that size have more than one occupant, and obviously you can’t use that space for living in and dedicated growth, particularly if you’re optimizing your growing space with red light, carbon dioxide, and heightened heat and humidity. Also skyscrapers cost something like $1000 a square foot, meaning your growing space for one person would cost something like a million dollars. Nor would this include much excess food, feed for meat animals, or for non-food elements like cotton for textiles, wood for lumber, or bio fuels for fuel or plastics.

We’ve played with these numbers before in the fusion article and some of our looks at space habitats and ships and I’ve usually found that a value of about 2000 square feet or 200 square meters is a pretty decent size with lots of padding and rounding up. Keep that number, rounded and somewhat arbitrary that it is, in mind for later. Most Arcology art that I’ve seen seems to just have the walls covered with plants and maybe some more inside getting non-optimal lighting. And the image those tend to paint, to me anyway, is essentially an over-sized building with houseplants and gardens, which is hardly revolutionary.

Our cities have featured plants for as long as we’ve had cities and keeping a small herb garden out back, on a windowsill, or on your roof was a classic way of slightly supplementing your diet or improving the taste of your meals while helping to mask all the odors associated to human habitation especially prior to the invention of modern plumbing and sanitation. There’s nothing terribly revolutionary about growing plants in or around buildings, but if you actually want to feed the inhabitants primarily off those you not only need a lot more space devoted to it but to adopt some pretty intensive measures to get those yields, as I just mentioned.

Concepts of Arcology

Concepts of Arcology

In comes the more proper image of giant buildings integrated into a more natural setting but one with mankind’s hand print on it in the forms of the hexagonal grid below. Arcologies are supposed to replace cities, so while you would expect early ones to sit next to a cityscape that portrayal shows us Arcologies the same way sticking a Model-T next to a bunch of horse drawn carriages show us a modern cars and roads. This article is essentially a two parter with another article looking at the notion of the entire planet being subsumed into one immense city and I’m forever trying to explain that the sort of dystopian, packed concrete forest shown to us in most examples of that is just off the mark.

Later in the article we’ll walk through an example Arcology only about as tall a tallest skyscraper nowadays and not all that wide and we’ll see how just having one these poking out of the forests every couple miles would let you easily house dozens of times our currently population, and see that heat not space is the real bottleneck to further growth. So this image of them towering on their own or in small clusters scattered throughout forest and farmland is far more accurate. Now this doesn’t mean an Arcology can’t have all its food production done inside instead, but to do that you almost have to have fusion and ultra-cheap, ultra-durable construction in terms of height too, and we need to talk a bit about Vertical Farming to explain that.

Vertical Farming has become quite a craze in recent years and I say craze with the full derogatory intent because it never makes any sort of economic sense to have your food supply, which takes a lot of space, grown inside skyscrapers, which often cost thousands of times more per foot of area than farmland does, and which really has few advantages economically or ecologically if you’ve got to run yourself on fossils fuels or solar power.

In the absence of fusion, to light an acre of farmland up with replicated sunlight is going to require a few million watts of electricity running for a couple thousand hours a crop, so that even if you’re very miserly and efficient with your power supply you are burning millions of kilowatt-hours, and hundreds of thousands of dollars, to light up one acre per crop yield. It’s only when you have an actual alternative to sunlight that this becomes viable. And just as reminder, if you’re in doors right now with light coming in through the window or from a light bulb, it’s not half as bright as the noon time sun, it’s more like a hundredth or a thousandth.

The noon time sun is about 100 Watts per square foot, a 100 Watts light bulb usually only produces about 10 Watts of visible light, and that’s being spread over a hundred or more square feet of floor and wall. The only reason LED lights, which produce strictly in the visible range, are even vaguely viable is that the super-majority of the sun’s light is not usable in photosynthesis, whereas LEDs can be tailored to emit a matching spectrum, and that plant’s can’t use most of the noon time sun light. So with LEDs you don’t need 100 Watts of sunlight per square foot and can get the same effect from maybe 5 watts of tailored light instead, less in most cases. That’s still prohibitively expensive, without fusion, but it also means you can light up a whole planet’s worth of surface area inside buildings without roasting the planet since you’re only adding 5% more heat to the setup, and we’ve discussed before some way of cooling planets and will look at that more in the follow up article. So that whole equation changes if you’ve got fusion. When you can exactly control the amount of and frequency of light and you control humidity, temperature, nutrient supply, the works, you can squeeze a lot of food out of an area and to the point that a large basement could produce the food for an entire family living in that house.

Cheap, sustainable power is a huge game changer, but so is ultra-cheap construction and automation. In that sort of context, a micro-arcology, a cabin in the woods, on first glance could look like any other, only you’d be surprised how lush and dense that forest was, and down in the basement there’s a couple level of hydroponics growing food and at night time little robots scurry out quietly to fertilize and tend to the forest, to harvest a bit of biomass, to water things, and so on. The notion of polyculture, which is mixing crops to optimize yields, is not very cost-efficient currently because it can be pretty manpower intensive. Like with fusion, the equation changes when you’ve got better robots. The big green grass lawn that is a staple of suburban America is a staple because its not very time consuming compared to elaborate gardens. We already see robots replacing lawn mowers and vacuums, when you’ve got robots cheap and sophisticated enough to scuttle around on orders from your house computer pruning trees and watering and weeding gardens you would expect to see that replace the green lawn setup because it’s just an initial capital outlay plus the occasional maintenance or replacement of robot when your dog or cat mauls it, and you’d see a lot more fresh produce being homegrown when they can just scuttle in from your garden or greenhouse and stick the stuff in the fridge. This is every bit as much Arcology as giant towers are.

So Arcologies as a concept is just self-contained, self-supporting habitats. That could include everything from domed cities on the Moon or Mars or the giant rotating habitats we’ve previously discussed, to tower buildings where everything is grown inside, all the way down to a small cabin in the woods. They needn’t be isolated from trade but the notion is minimalist, because you’re trying to do most of your consumption from local production.

But the giant building, if you do have fusion, can be one where everything is done not just nearby but totally inside the structure. Such structures could extend deep underground and high up into the air, and the control factors on their size run into two interesting problems. The first is strictly psychological, most folks would want a window view, so you aim to have hydroponics and factories and storage deep inside, the reverse of if you need sunlight for your food where the outside edge needs to be given over to hydroponics. In a fusion-powered setup you just have all these endless rooms lit mostly with red light to maximize photosynthesis with each room devoted to that being endless shelves of white or reflective material probably sealed off and mostly tended by robots.

In both cases you recycle your water, sewage, and air supply through there. The other problem is called the Elevator Conundrum. The elevator conundrum is a term used to describe the problem that while having elevators allows for tall buildings, they also limit the height of tall buildings since you need to provide more elevators for each floor you add on. Doubling the height of building means doubling the people in it and slightly more than doubling the number of elevator shafts you need since those elevators also need longer travel times for the extra floors. Each shaft takes the same place up on each floor, so if you double your elevators you ‘re doubling the portion of your building given over to it, and again probably a decent amount more since you need those elevators to spend more time moving to go from top to bottom.

This is a big deal with tall buildings, just as a quick example, if we needed 10% of the floor area to service a ten story building, say one that was 100×100 feet wide, 10,000 square feet per floor or 100,000 feet total, we’d have 10,000 square feet just devoted to elevators leaving only 90,000 for proper use. If we doubled that we’d needs 20% for elevators and our 200,000 square feet would need 40,000 for elevators and so we get 160,000 for other purposes, practically speaking probably less too from compensating for longer travel times. We doubled the area, we almost certainly more than doubled the construction cost, and yet we go from 90 to 160,000 usable footage and only got 78% more area. Adding ten more stories on, jumping to 30 floors and 300,000 total feet, and 30% devoted to elevators, give us only 210,000 feet for use, jumping to 40 stories, and 40% usable area, would give us only 240,000 usable square feet and at 50 stories we only get 250,000 feet, and at 60 stories we’re actually back down to 240,000 feet, and at 70 stories, 210,000.

So at a certain point you’re not even getting diminishing returns as you get less and less area from each new level while it costs far more to build each new level, with the elevator conundrum you eventually get a point where you actually have less usable area. And there’s similar 2D problems with roads in cities too. Needless to say there are a lot of partial solutions to these problems, double decker elevators, express and dedicated elevators, dispatching techniques and so on. And it’s quite a fascinating problem with a lot of math, but interestingly arcologies partially get around it. An Arcology being essentially self-contained you have a lot of low traffic areas and a much lower population per square foot ideally.

Remember early I said you’d need about 1-2000 square feet per person just for hydroponics, which doesn’t really need an elevator most days, whereas that’s a quite comfortable family sized apartment. You can also get away with a lot more levels because the first floor is no longer the primary destination for instance, and because there’s just more space per person. This doesn’t eliminate the elevator conundrum but it mitigates it an awful lot, and there’s never much point building higher than that would be a genuine concern for because you can always go wider instead and as we’ll see in the Ecumenopolis article even if you do every foot of your land and sea with Arcologies, so that all that’s left is to go up, you hit the heat wall long before the elevator conundrum becomes critical. Also looking at an Arcology, where construction needs to be cheap enough, either to build or maintain, that devoting the majority of it to food production is viable, does requires to discard the notion of cramped buildings entirely.

What is Arcology

What is Arcology

Arcologies are just something you don’t even build unless you’ve got the ability to make pretty spacious buildings in terms of individual area per person. We’ll look at that more in Ecumenopolis article but in short form, as long as you have to do your farming basically one level high, whether you’re doing that in land-inefficient but labor and cost-efficient open air farming or everything is being done in greenhouses, you just don’t need a lot of verticality to most of your buildings because it doesn’t benefit you.

Human living, working, and shopping areas just don’t take up much real space. You look at Hong Kong and New York, the two cities with the most skyscrapers, not only is neither of them even in the top 40 most densely populated cities, with the densest, Manilla, barely having 50 skyscrapers, but neither takes up much actual land area even though most of the buildings aren’t even shorter high rises let alone tall skyscrapers. Same as folks who don’t live in the country often forget how immense farms are, with larger ones often being bigger than cities, folks who mostly see metropolises on TV or going in for a shopping trip tend to forget that only a tiny fraction of the buildings in even the largest metropolises are 4 stories high or more, and only a small portion of those are skyscrapers.

You might need all of an entire continent devoted to feeding our current population but you could comfortably house the entire population in one or two story suburban style micro-mansions without even denting your total area. Suburban housing densities of 14,000 people a square mile is not even a little cramped, that’s like a quarter-acre lot per family, and that would fit the whole human population into half a million square miles. Which sounds huge but is about the size of Spain. So you only start housing most of your population in tall towers when building them has gotten so cheap per square foot that you can plausibly start thinking about doing most of your farming indoors too. We might build an Arcology principally for the prestige, same as building the tallest building, but don’t ever expect them to become normal things a significant fraction of the population lives in until we can actually grow food economically indoors. It just couldn’t happen. If it did though, if we could do it economically, you could toss out the cramped apartment concept because living area would have had to have gotten proportionally a lot cheaper. And you can overlap growing area with living space too as your fish tank becomes part of your water recycling and produces food, your hallways being lit have plants growing on the sides, maybe your window curtains are actually a mesh fruit vines grow in, that sort of idea.

Things we mostly don’t do now not because of space so much as time, doing them requires time and attention after all. Now there’s no optimal arrangement or size for these yet, so let’s walk through a conceptually and mathematically simple one. We’d previously said 1-2000 square feet was probably enough for food but let’s pad that out and remember we need other space too, and that we’re aiming for luxury and spaciousness.

We don’t dystopia much on this blog. Let’s say an Arcology needed to devote 10,000 square feet to each person, and that includes not just living area but all the shops, farms, elevators, warehouses, public buildings, offices, and factories you’d need. You want to cram everyone into a monolithic tower you might as well give them a lot of breathing space. And let’s assume a population of 5000 per Arcology, also not entirely arbitrary, many places like my own state of Ohio use 5000 people as the official transition number from village to city and it happens be a value we often use for colony considerations in terms of both Dunbar’s number and minimum gene-pool to avoid genetic bottlenecking. Means you can have a specialist in almost every field living on site, and more than one of most. Means you can hypothetically know everyone in your own tower but is still big enough you can easily avoid people you don’t like. Means school class sizes don’t have three or four people, or three or four thousand, per grade. 5000 is a good community size, it allows a lot of independence yet still massively benefits from cordial relations and trade with neighbors.

We could go bigger or smaller but it’s a solid number and a mathematically convenient one. So how much space is that? 5000 people needing an average of 10,000 square feet a piece for all their living, working, storage, recreation, and farming needs? Well its 50 million square feet, just under 2 square miles, about 4.6 square kilometers, just under a thousand acres or 500 Hectares. If we turn that into a 100 story high cylindrical building that would mean each circular floor needed to have half a million square feet and a radius of 400 feet.

That incidentally is just under 3 times larger than the world-recorder holder, China’s New Century Global Center, in floor area, 8 times bigger than the Pentagon, and 15 times bigger than Khalifa Tower in Dubai, which is 154 levels high. All of these are deigned to either house or be workspace for a lot more than 5000 people, but remember this is all inclusive. It’s your parks and shops and factories and farms too. Now we don’t really think of cylinders or circular floors as the optimum design for window space, in fact it is the exact opposite, the shape which minimizes that exterior surface per volume, but the structure I’ve just described still has 2500 feet of circumference times 100 levels, or 250,000 feet of possible windows, or 50 feet per person for a population of 5000. That’s a lot of windows, especially considering most people prefer to live with someone else.

We usually put the US coastline as being just under 100,000 miles, so if everyone lived in one of these and they only existed on the coast and only were spaced one per mile of coast you’d be able to pack about half a billion people into them, the population of the entire North American Continent, and leave the whole remainder of the continent over to forest if you wanted. If you just put one per square mile over the whole continent, keeping in mind that these only have a diameter of a sixth or seventh of that and would take up only a few percent of that square mile, you’d have ten million of these things with 50 billion people living in them, just in North America. Of course that would include tundra but an Arcology works just fine in tundra, desert, or ocean, or frankly on the moon, though they can generate a lot heat and would be harder to cool there.

Everything about Arcology

Everything about Arcology

We’ll look at that issue and maximum packing in Ecumenopolis but it’s kind of key to understand that this concept of larger human populations living in dystopian trash dumps and eating Soylent Green is just a figment of over-population concepts from earlier science fiction. If you’ve got the power, either by fusion or secondhand fusion by solar, your real control factor is waste heat, not space, not food, and certainly not how many forests you can pave over. We’ll talk about that more next time too. Now you can builder these wider, you can build them taller, but if you’re a regular on this blog it seems pretty silly to try to impress people with sheer size. Last week we were talking about Matrioshka Brains and those can make classic Dyson Spheres look small and those are a billion times bigger than a planet, so some ten-mile-high building is not exactly over-awing at this point. In contrast the Arcology I just described is quite tiny and it’s still so large that if it wanted to have that central atrium a lot of skyscrapers go for with some trees in it, you could keep a full grown redwood in it. Nothing is really stopping you, besides maybe the elevator conundrum, from building these things so they stretch a mile underground and poke up into the upper atmosphere either.

But larger Arcologies, pretty much anything bigger than our 5000 person one I outlined, start needing ventilation, cooling, and transport networks built into them that are best compared to the human arterial or nervous networks. One reason you’d want to build them near a coast besides the view, much like a power plant, which would presumably be in the basement of one of these anyway, you’d need to suck in a lot of water to cool the places, and that can have positive effects on the local ecology too if done right. For that matter a lot of things can be done when you’ve got cheap power and automation that boost local ecologies. I talked before about the notion of vertical reefs in the oceans, just having fusion powered strings of light emitting at a photosynthesis optimized spectrum of light, to let plants grow far more abundantly and far deeper in the ocean, and you can do something similar on land too if you’ve got fusion, making your forest areas much taller and lusher by supplementing natural light with some photosynthetic calibrated red light and watering systems and fertilizer.

There’s obviously a heat issue with something like that but it’s actually pretty minimal and considering some of the leviathan structures we’ve discussed elsewhere in the series, setting up solar shades between us and the sun that only blocked infrared light, which is again most of the sun’s emissions, would let you massively boost the amount of heat you could make on Earth without any ramifications to the ecology or aesthetics. Agriculture probably seems pretty boring compared to some of the subjects we look at on this blog and that’s probably why it tends to be a huge gaping hole in a lot of science fiction and futurism, fantasy too for that matter. Where you get your food from and how much food you can squeeze out of an area and how much labor that takes is a very big deal. These days we tend to grow crops as one giant field of all the same thing. The preferred way is polyculture where many different things are being grown to maximize the overall yield. That is more efficient, in terms of land or raw energy. What it isn’t more efficient in is equipment and manpower. Corn and wheat let you spew out a ton of calories from a large spot with very little human labor.

That’s why they’re so cheap, and part of why things like strawberries are so expensive since we still need actual humans to do the picking. One man with a tractor can tend hundreds of acres of cereal crops while it can take the equivalent of an entire man year of labor to pick one acre of strawberries, which can actually yield a higher weight per acre than stuff like corn, albeit most of that weightism water not calories. We’ve a lot of crops that give much better yields in terms of calories than our staple crops but just take too much manpower to produce cheaply. It’s the human time, or the cost of machinery, which is our production bottleneck. We need those people for other tasks. That’s why we don’t just dome over every last drop of growing land, even though doing so would hugely increase yields and save huge amounts of water. We can still spend less time per calorie yielded by open air farming and have more than sufficient land to feed the population that way. As the dynamic shifts, either because we have more people than open air farming can supports have to go for more time-intensive but calorie-intensive production, or we get better robots, or we can spew out polycarbonate greenhouse sheeting for pennies on the dollar, our farms will begin shifting and probably our diet too.

Many luxury crops that require a lot manpower to produce or have very touchy growing conditions would become more common and more to the point you can adapt elements of polyculture into industrial scale farming. And it wouldn’t always need to be robots either, I remember an example from Gregory Benford’s Galactic Center Series, coincidentally the earliest book I know of to reference arcologies by name, where they’d gene-tweaked their ants to go plant and harvest their corn, dutifully taking it kernel by kernel to silos and taking their share of the crop back to the hive. They didn’t use robots because robots were the bad guys in that series. Still while robotics is great stuff genetic engineering has its options too, for instance finding a way to make plants able to run on infrared light or green light too. Genetic Engineering like robotics is one of those controversial topics that some folks are fine with and others hate but I wanted to toss it out there as a reminder there’s lots of options. Most livestock tend to be inefficient grazers, trampling and ruining as much as they eat if you could tweak them or the things they’re eating to avoid that for instance you get twice your yield.

Arcology is a pretty broad-spectrum concept as I’ve been trying to emphasize and it really does extend across a lot of topics and disciplines and you try to fit the right one for what you want, what you can do, and what you’re willing to do. There are these giant climate-controlled warehouses where we grow lettuce for instance where they plant the suckers on little rafts on one end and pick them down on the other end and it just floats through like a slow conveyor belt, and you can expand the rafts the seedlings are on so you’re not wasting sunlight on them when they’re small. It’s not hard for me to imagine adapting that sort of concept to feeding livestock, like some big turf wheel that comes out at the trough and rolls slowly around through compact chambers spraying it with light and nutrients and rotating through like a conveyor belt over the course of a week. And there’s no reason you can’t double-dip on that to be raising fish off the water system being used or sucking the methane the cows are producing off be used as feedstock for fertilizer or plastics too.

Again our bottleneck is a manpower and brainpower thing and increased automation, increased population, and so on really changes the playing field. That’s a topic we’ve explored more in the article on Ecumenopolises, where we’ll continue to blast away at this sort of Malthusian Apocalypse Myth that always seems so fixated on portraying humans and industrialized civilization as either intensely sterile or filthy places, and try to integrate how science and technology can allow more Eden-like setups without needing to decrease how many people we have and quite the opposite, actually have more people enjoying a higher standard of living without having to sacrifice many of things that we tend to feel are very important to who we are too.

Lot of concepts today, as we tinkered with the classic image of the giant super skyscraper Arcology, and more next time, make sure to subscribe to our YouTube channel and like our Social network pages if you want alerts when that and other articles come out. If you enjoyed the article, please let me know in comments and share the article with others,  questions and comments are welcome, and you can explore other neat concepts like this by reading other articles in EduQuarks. Thanks for reading, and have a great day!