Muddied Waters on Local Consumption and Energy Efficiency

I have been paying attention recently to the local sustainability and economy debate. Now comes word that the calculus for evaluating energy efficiency by consuming locally may actually be more complex than advocates have let on:

Discussing the need to rethink our food system in terms of distances traveled, ["Eat Local" Advocate Barbara] Kingsolver writes, “this isn’t rocket science” .... But ... when you factor in the externalities of life-cycle assessments, it sort of is rocket science.

By incorporating more measures, scientists reached surprising conclusions. Most notably, they found that lamb raised on New Zealand’s fertile pastures and shipped by boat to the U.K. consumed 688 kilograms of carbon dioxide emissions per ton. By contrast, stock produced within the U.K.’s poorly adapted pastures consumed 2,849 kilograms per ton. In other words, it is four times more energy efficient for Londoners to buy lamb imported from the other side of the world than to buy it from a producer in their backyard.

There seems to be an "ecology of scale" involved in the global market, that strictly local common sense fails to grasp:

If you’re wondering what it is like to eat local in the wrong place: It sucks.

Read the article to the end for the author's counter-proposals, which involve more regional development and hybrid transportation, and he also has a shorter op-ed piece on the subject in today's New York Times.