On multiple environmental measures, “peecycling” almost always comes out ahead
December 22, 2020
Manufacturing the fertilizer on which much of modern agriculture depends takes a heavy environmental toll. The phosphorus in commercial fertilizer comes from phosphate rock, a non-renewable resource, while nitrogen comes from natural gas and requires a lot of energy to produce.
But there’s an endless stream of renewable phosphorus and nitrogen available: yes, we’re talking about urine. And meanwhile, lots of energy and expense goes to removing nutrients like nitrogen and phosphorus from municipal wastewater.
“Both conventional wastewater treatment and fertilizer production are carbon intensive processes,” says Gregory Keoleian, director of the Center for Sustainable Systems at the University of Michigan in Ann Arbor. “Flushing urine with its valuable nutrients down toilets for processing in energy intensive wastewater treatment plants makes no sense.”