The food system in different countries uses a massive amount of energy from start to finish. In the U.S. they consume as much energy preparing and transporting food as France uses to power the entire country for a year.
Food systems around the world account for about 30 percent of the world’s total energy consumption. Since most food systems are run primarily on fossil fuels, that means they also account for 20 percent of our global greenhouse gas emissions.
These emissions take place at every step of the food chain. Manure and fertilizer give off nitrous oxide while cattle and other animals produce methane. Machinery requires diesel and gasoline, and the entire process is fueled by coal and natural gas power plants, creating carbon dioxide.
The energy in food production can be broken down into four parts: agriculture, transportation, processing, and handling.
This accounts for everything involved in the growth and cultivation of food crops. 60 percent of this energy is consumed directly in the use of gasoline, diesel, electricity and natural gas, while the rest is indirect through fertilizer and pesticide production. In total, agriculture consumes roughly 2.1 quadrillion Btu of energy each year in the US, enough to power the entire country of Norway.
The transportation of food from farm to table accounts for just under 14 percent of the energy that goes into producing food (U.S. numbers). Romania could power itself for a year on the 1.4 quadrillion Btu it takes to ship avocadoes from South America (among other tasty imports).
Food processing refers to the transformation of raw ingredients into a food product, in other words, turning raw corn into cereal and the like. This section of the system makes up about 16 percent of the total (U.S. numbers). This breaks down to about 1.6 quadrillion Btu per year, equivalent to the total energy use of Nigeria.
Food handling is by far the largest sector of energy in producing food, and accounts for nearly half of the energy used in food production – over 49 percent (U.S. numbers). This piece of the system includes retail, restaurants, packaging, and consumers. The energy used to package milk and keep it refrigerated in the grocery store and at home falls into this category. At 5 quadrillion Btu, the food handling sector’s total energy is more than enough to power a year of life in Taiwan.
Energy efficient foods
Certain foods require less energy to produce than others, whether because it requires less land and water or because there are fewer industrial processes needed to produce it. The most energy efficient foods include wheat, beans, fish, eggs, nuts and other non-resource-intensive products.
The least energy efficient foods are animal-based products, particularly beef, lamb and goat. This is because beef requires up to 20 times more resources and emits 20 times more greenhouse gas emission than plant-based protein sources. Poultry and pork use slightly less energy but are still far bigger emitters than plant products.
This doesn’t mean you have to be a vegetarian to cut down energy use. Just reducing the amount of meat and dairy you eat can allow you to have a much lower impact diet. Regardless, both meat-based and vegetarian diets rely heavily on fossil fuels, so neither is sustainable long-term in the current food system.
How to reduce food system energy use
Because so much of the energy used in food production comes from non-renewable resources, it’s important to make the food system more energy efficient. A few key ways to start making a difference at home are:
- Buy only as much food as you eat. One of the easiest ways to help conserve energy in food production is to waste less. It’s estimated that 40 percent of food in the U.S. goes uneaten. In 2017, that added up to 38 million tons of food waste. As a comparison, that’s the weight of 38 million polar bears, 5.5 million elephants, or nearly 300,000 blue whales.
- Buy food that is locally sourced. Shop at local farmers markets instead of buying produce at the grocery store. You’ll be supporting local farmers and saving the energy needed to transport perishable foods from across the world.
- Invest in energy-efficient food storage. Get an EnergyStar refrigerator, which use 20%-30% less energy. Also, keep your refrigerator fully stocked. If you don’t have enough food, keep containers of water in there instead. It may sound counterintuitive, but your refrigerator works most efficiently when it’s full.