My grubby little town was full of young men in big trucks and muscle cars who had come north to make their fortunes in the oil fields. During oil booms they kept the bars hopping and the hookers busy, dropping hundred dollar bills like candy…When the wells ran dry the young men disappeared, shops shuttered their windows, and the town shrank. New oil discoveries brought them back, with all of the goldrush excitement and disarray that accompanied them.
I remember the sunny day—well into my Ph.D. work—when I first read that each calorie of energy I got from food required seven to ten calories from fossil fuels to get to my plate. I was stunned.
Surely this couldn’t be true. I, like other living organisms, got my energy from plants, which got it from the sun. Of course I knew it took some petroleum to farm, process, package, haul, and market food, but I still considered food a renewable resource.
I checked other sources, and found that anybody who took a serious look at the energy balance of an industrialized food system reached a similar conclusion: My food was much more nonrenewable than renewable. The young men in the oil patch were doing more to feed me than the farmers.
I knew how fickle those young men were. The sun would keep shining, but the oil would run out, and they would be gone. I didn’t want my food supply to depend on them, and I knew it didn’t have to. For most of human history we, like other animals, got by on renewable energy. We used muscle power for farm tools and food hauling. We ate fresh food when it was available, keeping what we could in root cellars or storing it longer by pickling, salting, fermenting, and drying. We cooked and heated with wood fires. We packaged our food in ceramic jars, wooden boxes, leaves, and paper. Our diets were shaped by where we lived, and changed with the seasons. We lost a lot of food to spoilage.
Only in the past century and a half did we start to invest a lot of fossil energy in our food system. The 1840s brought a diverse array of new factory-made farm machines that made farming easier but demanded that farmers raise enough cash crops to pay for them. The wheel-blade can opener was patented in 1870. A glass-bottle blowing machine made mass production of jars possible in 1903. By 1910 we were beginning to make synthetic nitrogen fertilizer and use gasoline-powered tractors. Frozen foods, fridges, freezers, and refrigerated trucks showed up in the early 1930s and 1940s.
Each ingenious new invention made it easier to get food to the plate—at an energy cost. In 1840 the U.S. food system depended almost entirely on renewable energy sources, including labor from 70 percent (12 million) of the 17 million Americans of the day, more than 2 million of whom were enslaved.1 By 1900 the population had grown to 76 million, less than 40 percent (30 million) farmed, slavery had finally been abolished, and the food system consumed about 3 quadrillion Btu of fossil fuel.2
Today less than 1 percent of the population farms, and those 2 million farmers feed more than 300 million of their fellow citizens. The entire U.S. food system consumes about 10 quadrillion Btu from fossil fuel every year: 1 quadrillion Btu to make farm inputs like fuel, fertilizer, and machinery; 1 quadrillion to farm; 1 quadrillion to haul; 4 quadrillion to process, package, and sell food; and 3 quadrillion to run the fridges, freezers, stoves, and the other appliances that fill our home kitchens.3 The vast majority of energy used to get food to our plates is used after the food leaves the farm. Our kitchens consume far more energy than our farms.
…Food processing, packaging, storage, and preparation account for most of the energy cost of most of our food.13 If local food economies can reduce the need for these elements of the food system they will succeed in reducing our fossil-fuel dependence dramatically. Whole, unprocessed foods—often promoted for their health benefits—offer tremendous energy benefits too. If we’re concerned about food-system energy, it’s hard to beat whole grains, protein-rich beans (stored dry), and fresh produce, prepared simply. Yum!
About The Post Carbon Reader
How do population, water, energy, food, and climate issues impact one another? What can we do to address one problem without making the others worse? The Post Carbon Reader features essays by some of the world’s most provocative thinkers on the key issues shaping our new century, from renewable energy and urban agriculture to social justice and community resilience. This insightful collection takes a hard-nosed look at the interconnected threats of our global sustainability quandary and presents some of the most promising responses.
Contributors to The Post Carbon Reader are some of the world’s leading sustainability thinkers, including Bill McKibben, Richard Heinberg, Stephanie Mills, David Orr, Wes Jackson, Erika Allen, Gloria Flora, and dozens more.