“Sky farms are fantastically beautiful, with their kilometer long networks of glass framed in grids of metal, and the sunlight shining through jungles of vegetation inside. When one of them catches the light, you can see the refracted beauty for miles; they are life-giving stars on a desolate planet…gardens on the wing.”
— Lady Deirdre Skye, “Planet Dreams”
Some of my favorite quotes come when, as with this one, Reynolds turns his hand to describing the wonders of the future. Here, Lady Deirdre paints a picture of the massive greenhouse-like structures floating through space. It’s almost impossible not to imagine what they must look like, first in a close-up from orbit and then from the ground beneath. For one thing, they’re just so huge. Each one is a full kilometer of glass girded by plasma steel, filled to the brim with an edible Earthly ecosystem.
In the game, sky hydroponics labs are the first kinds of satellite a faction can launch after developing the Orbital Spaceflight technology. Like all satellites, their benefits are spread throughout the whole of the faction that builds them. They’re a little like more like miniature secret projects than base facilities.
One neat bonus that usually accompanies this quote is that any remaining unexplored territory on the map is revealed. The idea is that the first satellites can perform a mapping function as well as serving their normal economic purpose. Games like SMAC are commonly referred to as “4X” games, where the first X stands for eXploration, so this serves to draw a definitive close to the initial exploration phase of the game. Henceforth, the remainder of the game takes place on a known board.
Each orbiting sky farm delivers one nutrient to each base. The number of bonus nutrients is capped at the number of citizens in the base, so building more sky farms than the size of the largest base in the faction is a waste. And this benefit is halved if the base doesn’t have an Aerospace Complex, presumably to model the difficulty in getting the goods back down from space to a location that isn’t properly equipped to receive them.
As the player certainly is aware by this point, just a couple extra nutrients can be the difference between a rapidly growing base and a stagnant one. Since every citizen requires two nutrients to continue to survive, this means that a base needs to bring into cultivation a new square with at least a two nutrient yield for each pop point. But sky farms radically change that calculus by essentially halving the cost per pop point. This literal manna from the heavens helps break the game wide open. Suddenly it is not at all difficult for virtually any base to grow up to its population cap.
But all of these concerns and musings pale compared to the most interesting question of all. How can it possibly be a sensible idea to build these? In modern times, the reason why satellites and space travel are so expensive are because it is so expensive to get mass into orbit. This is presumably still true just as the space industry gets going again. And food is cheap and heavy. Growing more food is therefore not an obvious killer app for space travel.
Only one potential reason comes to mind. The player has seen that farms and condensers – the ground-bound versions of these sky farms – have a significantly negative impact on the ecology of Planet. Growing the necessary nutrients in space is therefore best seen as a compromise. If a faction keeps many of the Earth plants they need to thrive in orbit, they can help to avoid the inevitable fungal encroachments and mind worm attacks that come from the more straightforward solution to the problem.