EIA: “The U.S. agriculture industry used nearly 800 trillion British thermal units (Btu) of energy in 2012, or about as much primary energy as the entire state of Utah. Agricultural energy consumption includes energy needed to grow and harvest crops and energy needed to grow livestock. Crop operations consume much more energy than livestock operations, and energy expenditures for crops account for a higher percentage of farm operating costs. Agricultural energy consumption includes both direct and indirect energy consumption. Direct energy consumption includes the use of diesel, electricity, propane, natural gas, and renewable fuels for activities on the farm. Indirect energy consumption includes the use of fuel and feedstock (especially natural gas) in the manufacturing of agricultural chemicals such as fertilizers and pesticides. Energy makes up a significant part of operating expenditures for most crops, especially when considering indirect energy expenditures on fertilizer, because the production of fertilizer is extremely energy-intensive, requiring large amounts of natural gas. For some crops like oats, corn, wheat, and barley, energy and fertilizer expenditures combined make up more than half of total operating expenses. The proportion of direct to indirect energy use varies by crop. For example, corn, which is also used as an energy input for ethanol production, has relatively low direct fuel expenditures but has the highest percentage of fertilizer expenditures.”