Food wastage accounts for two percent of US energy use: Study

Over a quarter of the American food supply ends up in the garbage – and the energy used to produce this wasted food accounts for about two percent of total US energy use, according to new research.

The study, published in the journal Environmental Science and Technology, calculated that about 350bn barrels of oil could be saved if this food waste were eliminated. The researchers wrote that this is “substantial when compared to other energy conservation and production proposals.”

And the figure is likely to be on the low side, the authors said. To estimate levels of food wastage, they used data from a 1995 US Department of Agriculture (USDA) report, which found 27 percent of the US food supply is wasted. However, it only included food loss from retailers, food service establishments and consumers – but did not include the “significant food losses from other components of the food processing chain”. Nor was the energy required to dispose of food waste included in the study.

The authors pointed out that although meat uses the most energy to produce, the foods associated with the greatest energy loss are dairy and vegetables, as they are more likely to be thrown out.

The researchers wrote: “The energy embedded in wasted food represents a substantial target for decreasing energy consumption in the US. A decrease in food waste must be accompanied with a retooling of the food supply chain to ensure that the energy consumed during food production does in fact decrease with a decrease in food waste.”

In March this year, the USDA reported that about 15.7 percent of total energy expenditure in the United States was used for food production in 2007.

The full study is available online here.

Source: Environmental Science and Technology

2010, 44 (16), pp. 6464–6469

“Wasted Food, Wasted Energy: The Embedded Energy in Food Waste in the United States”

Authors: Amanda D. Cuéllar, Michael E. Webber.