Decoder: Miles to Go Before You Eat Why it pays to buy locally grown food by Paul Rauber
Posted May 31, 2006; amended May 2009 Editor's note: Subsequent to the publication of this feature, Sierra learned that there was a calculation error in the original paper on which the article was based, "The Load Less Traveled" (Leopold Center for Sustainable Agriculture, 2002). In addition, Sierra's own calculations failed to account for the differing fuel-energy values of gasoline (light truck), diesel (commercial truck), bunker oil (ship), and jet fuel (air). We also neglected to cite the weight of our example produce; e.g., the potato was large, weighing one pound. Together, these errors led us to significantly overstate the amount of fuel needed to move the items to market.
On May 31, 2006, we posted the Leopold Center's recalculations of the fuel requirements to transport various produce to market. Unfortunately, we recently learned that those calculations were also in error. The figures below are the center's new calculations using a different (and, they think, more reliable) estimate of the energy requirement by mode of transportation. By chance the results are very similar to the miscalculated totals. Please note that for the purpose of this example, the "market" was designated to be Des Moines, Iowa.
Calculations for estimating energy (fuel) requirements to transport various produce: