A clearer picture of the energy footprint of irrigation could help make water and energy use more sustainable.
Agricultural irrigation is the largest consumptive use of water in the United States, supporting an enormous farming economy and requiring thousands of pumps.
This niche of the energy-water-food nexus was the subject of research by undergraduate student Emily Dicataldo and professor Rob Sowby in BYU's Civil and Construction Engineering Sustainability Lab. They estimated that the pumping associated with agricultural irrigation consumes about 1% of all U.S. electricity (37.5 of 4,000 terawatt-hours per year).
"One percent may not sound like much, but it's a piece of the pie no one has seriously looked at until now," said Sowby. "And in states with concentrated irrigation like California, Idaho, and Nebraska, the proportion is even greater."
"This is a great starting point for conversations about better characterizing and optimizing irrigation-related energy use," said Dicataldo, a civil engineering senior.
While energy information is directly available for other sectors, irrigators do not report to any centralized agency, so quantifying their resource use is difficult. Sowby and Dicataldo laid out a repeatable approach that synthesizes existing data from various government sources.
"Besides coming up with a number, we want to be able to update that number as irrigation techniques, water use, and crop choices change," Sowby said. "Using open data allows us to do just that."
Their article, The Energy Footprint of U.S. Irrigation: A First Estimate from Open Data, was published in the open-access journal Energy Nexus.