from: The Energy Cost of Food
By Eric Garza
... Just how much energy does it take to fuel a food system? The answer, of course, depends on where you are. Based on data from the United States Department of Agriculture, in 2002 it required just over 12 calories of energy to produce, process, distribute and prepare one calorie of food in the US once waste and spoilage are accounted for.2 Of these, 1.6 fuel calories were used in the agricultural sector, while another 2.7 were used to process and package food. Distribution, which includes long distance transportation, wholesale and retail sales, and food service enterprises such as restaurants and caterers, used another 4.3 calories, while food-related household energy use added the final 3.4 calories to the tab. This figure has been increasing; it took just over 14 fuel calories to deliver a calorie of consumed food in 2007, and has almost certainly increased since.
As high as the 14 calorie figure might seem, it’s surely an underestimate. The report from which these data were derived left out a number of segments of the US food system, including research and development, waste disposal, water provision and treatment, food system governance, and the energy needed to provide healthcare for those suffering from maladies brought about by poor food choices, among others. A more expansive assessment of energy use in the US food system, one that attempted to account for food’s entire life cycle from soil to consumers and back to soil, would likely estimate a total energy demand of 15-20 calories per consumed food calorie, or more. To put these statistics into perspective, 15 fuel calories equates, in thermal energy terms, to the average American drinking 1.3 gallons of gasoline along with their typical daily food intake. That’s nearly 480 gallons of gasoline per year, an amount on par with what the average American burns in their car. The US food system is more energy intensive than most, but high fuel demand in the service of food procurement is quickly becoming the norm around the world.