An op-ed in the New York Times illustrates why those concerned about energy use and “sustainability” should not be concerned about farms and being locavores, but about households energy usage

Overall, transportation accounts for about 14 percent of the total energy consumed by the American food system.

Other favorite targets of sustainability advocates include the fertilizers and chemicals used in modern farming. But their share of the food system’s energy use is even lower, about 8 percent.

The real energy hog, it turns out, is not industrial agriculture at all, but you and me. Home preparation and storage account for 32 percent of all energy use in our food system, the largest component by far.

Driving to a nearby Walmart to buy factory foods may be more environmentally sound if it saves you a car trip because you’re going there anyway, or if it’s closer than wherever it is you buy local food. I don’t know if anyone has quantified the extent to which big boxes have helped the environment by allowing one-stop shopping, but it seems it would be significant.

And it sounds like foodies should be focusing on which ways to prepare food conserve the most energy. Is microwaving your food the most environmentally friendly thing you can do? Clearly, locavores and greens are focusing on the wrong part of the food production chain to wring energy savings out of. The urban farmer/locavore/foodie aesthetic is a high status one though; the Walmart shopper/microwaver is not.

The piece closes with this paragraph which I will second and should be repeated to urban farmers everywhere:

The best way to make the most of these truly precious resources of land, favorable climates and human labor is to grow lettuce, oranges, wheat, peppers, bananas, whatever, in the places where they grow best and with the most efficient technologies — and then pay the relatively tiny energy cost to get them to market, as we do with every other commodity in the economy. Sometimes that means growing vegetables in your backyard. Sometimes that means buying vegetables grown in California or Costa Rica.