Carrying on from yesterday's introduction of vertical farming, I thought I would try to put together a little bit more of a primer for you.
First off, Discovery channel offers this video. Basic, but effective:
First and foremost among the reasons we "need" vertical farming* is that we have a growing population of humans what need feeding, contrasted with an ever-shrinking amount of arable land for farming. If that sounds familiar, it's because it's pretty much what Thomas Malthus was talking about a couple hundred years ago in England (minus the whole bit about vertical farms, and plus a whole lot of OH GOD OH GOD WE'RE ALL GONNA DIE!). We've had pretty good luck so far avoiding the direst of his predictions, and that's because - surprise surprise - people aren't actually that eager to die in droves, and we've been perfecting farming technologies that have allowed us to greatly increase the crop yield of our finite fields. Unfortunately, not all of these technologies are without cost: chemical fertilizers and pesticides have been contaminating water and animal tissues since their respective inventions, and the high-yield monocultures that we grow today are leaving us ever more succeptable to devastating blights, should they arise. I think I would argue that while these technologies have definitely served us well in the past, they're a bit of a misstep overall. We're looking at the problem a little bit backwards. In its early phases, agriculture was the creation of a controlled environment where before humans had to deal with the fortune that nature dealt them. As an extension of that control, synthetic fertilizers and pesticides seem more or less logical...but now that we can grow food indoors with hydroponics/aeroponics, we can leapfrog the whole problem of trying to reign nature in by building the ultimate controlled environment quite literally across the street.
*Ok, so we don't actually need it. We could just let people die or keep poisoning the Earth.
Hydroponics is probably a technology you've already heard of: you grow plants in nutrient-infused water, it saves space and doesn't require dirt, etc. Aeroponics is pretty much the same deal, except that rather than being immersed in water, the roots of a crop are sprayed with it. The water requirements of an aeroponic crop are comparatively much lower than that of a conventionally or hydroponically grown one. And once you've bypassed the need for dirt, you can pretty much stack your crops in racks on top of each other (with a little root space in between). I was ballparking the efficiency of a vertical farm much, MUCH too low when I guessed fifty times that of a conventional farm yesterday. Scientfic American puts the figure somewhere around five hundred times more efficient (they say a one-city block x 30 story building could equal 2400 acres of farmland, and it seems a Manhattan city block is about 5-6 acres)...and I missed another interesting point: a lot of these designs also include living space. I'm not sure there's anything necessarily superior about this configuration, but I'm a fan of the idea anyhow.
The million-dollar (well, probably 5 or 20 million in today's dollars) question is, of course, whether or not anyone is actually going to do it. On paper it's a pretty perfect solution: piles of local organic food without pests and presumably at affordable prices (even if the infrastructure's pricey you'll be killing the competition in volume and on top of that your growing season never ends!). It's a nice change of pace for your city skyline, and it reforges a lost connection between people and their food. Unfortunately, I think there's a potential chicken-and-egg problem: since that link has been severed, does anyone really care enough about food to support such an undertaking? Would vertical farming even win a few percentage points as a plank in a mayoral platform? Obviously I can't say, but I'm not holding my breath...
The closest thing I've seen so far is a planned eco-city in the UAE called "Masdar". It's supposed to be some kind of sustainable paradise. Solar powered, more or less self-sufficient, etc. Of course, the UAE is probably not the best place for conventional agriculture...but they do have the kind of venture capital to look into building a vertical farm. Even if it's just for show now, it should subsidize the startup costs of future iterations by getting all the kinks worked out beforehand. So while I may be a little too cynical to book my tickets for Abu Dhabi just yet, I'll be keeping my eyes on this bizarrely utopian project (set to open in this quarter, no less!)
That's all I've got for now. If I come across some more interesting material I will tack it on somewhere. Until tomorrow, goodnight