Food Energy: The Invisible Energy Sink Behind What's on Your Plate

Colin Hyatt
November 27, 2016

Submitted as coursework for PH240, Stanford University, Fall 2016


Fig. 1: This is an example of a Machine used on farms that is much more efficient than humans but also requires more energy. (Source: Wikipedia Commons)

Have you ever sat down for a meal and thought about where the food you are eating was grown and how much energy was used in order to grow it? Due to huge increases in both technology and efficient global transport networks, the amount of energy being consumed by the food industry has skyrocketed. [1] Farmers are being replaced by machines, which use energy, and food is being shipped all over the world, resulting in huge energy expenditures. Global warming is a widely talked about topic, but rarely do you hear the food and agriculture industries brought up in the same discussion. When talking about global warming, most people think about the industrial and transportation sectors, but greenhouse-gas emissions from the agriculture sector account for about 22% of global total emissions; this contribution is similar to that of industry and greater than that of transport. [2] Just by consciously making an effort to buy locally grown food, it is possible to greatly reduce the energy spent in the food industry and greenhouse gas emissions.

Food Transportation

The fact that food is being transported all over the world is not necessarily a bad thing, but in most cases, it is done so unnecessarily resulting in unneeded wastes of energy and greenhouse gas emissions. In many cases, produce is shipped thousands of miles to locations where the same produce is grown much closer. Although some of the shipping is needed a lot of it is actually unnecessary. A quote from a LA times article said, " California squid are being caught, frozen, sent to China, unfrozen, processed, refrozen and sent back to the United States in giant 50,000-pound shipping containers." [3] Due to the huge increases in technology and the globalization of the earth, it has made it possible for people to save money by buying products from far away and having those products shipped to them instead of buying them locally. This global food exchange only makes sense financially because the true cost, which includes the contributions to climate change, is never taken into account. Humans are choosing to save a couple bucks in exchange for much higher energy expenditures and green house gas emissions.

Energy Cost of Production and the Industrialization of Farming

Food provides energy and nutrients, but it also requires the expenditure of energy to be produced. The amount of people who are involved in farming has declined greatly in the last decade and continues to decline. At the same time, the amount of work of animals has declined to almost nothing. Fewer farmers are now producing more food than ever before with basically no help from work animals. This has been made possible by new technologies and industrialization. [1] Farmers and work animals are being replaced with machines. This is hugely beneficial to the farmers because it is much more efficient, but it drives the energy input through the roof.

In nature, plants preform photosynthesis which in basic terms transforms the suns energy into food. This process is renewable and produces energy, but the industrialization of agriculture has reversed this. "Instead of producing energy, industrial agriculture consumes it, through the addiction to fossil fuel-powered machinery and petroleum-based agrochemicals." [3] This process is widely used because it is highly efficient and highly profitable for the farmer. Without having to pay for the environmental cost of the huge energy input this process is highly efficient and highly profitable. [3]

Essentially the worlds food systems have become highly industrialized. If you were to compare a farm from 50 years ago to a present day farm they would look completely different. Farms from 50 years ago would look much like small scale sustainable farm today. They would rely on people power, not huge machines, and nature instead of chemicals and fertilizers. [3] As illustrated in Fig. 1, most farms are much different now. Most farms only grow one or two crops and use huge machines and pesticides in order to increase crop yields and decrease labor time. This method is much more efficient than farming used to be, but it uses much more energy and is much more harmful to the environment.


Overall Farming has changed dramatically from what it used to be and with this change came the ever increasing energy usage in the farming sector. The huge increases in technology and globalization has allowed the global food exchange system to reach a point where they are using energy unnecessarily. This coupled with the new farming techniques of using machines, chemicals, and fertilizers instead of humans, work animals, and nature have caused the energy use of the food sector to increase dramatically. A simple way that you can help change this and reduce the huge amount of energy used to produce your food is to but food produced locally and food from small scale sustainable farms, instead of industrial farms.

© Colin Hyatt. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.


[1] J. S. Steinhart and C. E. Steinhart, "Energy Use in the US Food System," Science 184, 307 (1974).

[2] A. J. McMichael , "Food, Livestock Production, Energy, Climate Change, and Health," Lancet 370, 1253 (2007).

[3] P. Greenberg, "The Long Journey of 'Local' Seafood to Your Plate," Los Angeles Times, 11 Jul 14.