Agricultural Energy Use at All-Time Low
Leonard Gianessi, Ashley Williams -
Thanks to advances in crop protection and management, agriculture has seen a dramatic decrease in energy use in recent decades. Since 1973, farm output has grown 63 percent while direct energy consumption has declined 26 percent. And the news gets even better - direct energy use per unit of agricultural output is 50 percent less today than it was in the 1970s!
What is behind these impressive numbers? Spurred on by spikes in energy costs in the early ’70s and again in the ’80s, the agriculture industry – like many others – sought ways to maximize efficiencies. An increase in conservation tillage, coupled with the safe and effective use of herbicides, helped significantly decrease energy use and costs.
Conservation tillage is a method of leaving residue from a previous years crop to reduce soil erosion and run-off. In order to gain maximum benefit from conservation tillage, a minimum of 30 percent (up to 70 percent) of the soil surface is covered with residue such as corn stalks or wheat stubble.
The utilization of conservation tillage can reduce soil erosion by as much as 60-90 percent, and results in benefits ranging from water conservation to reduced energy costs from fewer trips across the field. Coupled with the safe and effective use of crop protection products that offer protection from insects and other potential harm, these methods have helped increase yield and decrease costs.
As a result, the total direct and indirect energy used in agriculture accounted for about 5 percent of U.S. energy use in 1978, and is down to approximately 1.5 percent today. For additional statistics and details please visit CLF case study number 32.