Why cities might not be the best place for large-scale, hi-tech food production — food-miles notwithstanding
Cities offer a lot of environmental benefits, at least compared to the alternatives. There are many reasons this is so, but they all spring from a fairly basic fact: cities are built for people. Lots of people, densely packed, sharing resources. Innovations that encourage or take advantage of that density are likely to make cities more sustainable. And innovations that undermine density have a lot of work to do to overcome their inherent environmental disadvantages.
New York City, for example, recently released an ambitious plan to slash municipal carbon emissions by almost two million metric tons per year. Fully 16% of total life cycle reductions will come from a new rail and barge network built for the express purpose of hauling garbage. No one will appear on The Colbert Report to plug the new garbage barges, but the system will eliminate five million vehicle miles per year. Less congestion, less noise, less air pollution, and less greenhouse gas emissions. New York’s size and density make this project possible. Urban vertical farms, on the other hand, fail miserably on this score. Land is one of the primary inputs for agriculture, which is why we don’t expect to see corn growing in lower Manhattan. Such spaces are better reserved for people, mass transit, mass entertainment, and businesses that depend primarily on human capital. Our collective confusion on this point seems to be most acute when the topic is food. We intuitively understand that it doesn’t really make sense to manufacture, say, iPods in small factories scattered across hundreds of urban centers, even though iPods are consumed in just about every city in the world. We readily grasp that the economics wouldn’t work out, and we probably even understand that such a scheme wouldn’t help the environment. Efficiency benefits more than just the bottom line.
from “Cities are for People: The Limits of Localism,” by Adam Stein, WorldChanging, 8 August 2008