A team of University of California, Riverside Bourns College of Engineering students have won an EPA student design contest for developing an exhaust aftertreatment device that cuts CO, NOx and PM emissions from lawnmowers. EPA estimates that a standard gasoline-powered lawn mower emits 11 times the air pollution of a new car for each hour of operation.
The device is a L-shaped piece of stainless steel with filter and catalyst that attaches to the lawnmower where its muffler was. When tested, the device reduced carbon monoxide (CO) by 87%; NOx by 67% and particulate matter (PM) by 44%. An improved version of the device eliminated 93% of particulate matter emissions.
The team, which calls itself NOx-Out, believes there is a market for the device for lawnmower manufacturers and current lawnmower owners, especially operators of landscape companies, who could retrofit their existing gasoline-powered lawnmower. The device has the added benefits of reducing noise from the lawnmower and the smell of gasoline.
The students—Timothy Chow, Brian Cruz, Jonathan Matson and Wartini Ng, all of whom just graduated—won a phase one grant of $15,000 as part of the EPA’s P3 (People, Prosperity and the Planet) competition. Next year a new group of students—Anna Almario, Priyanka Singh and Alyssa Yan—will take over the project and compete for a $90,000 phase two grant.
All the students have been advised by Kawai Tam, a lecturer at the Bourns College of Engineering, Phillip Christopher, an assistant professor of chemical and environmental engineering, and David Cocker, a professor of chemical and environmental engineering.
The student team that just graduated inherited the project from another team of students that started it before graduating in 2013. They were: Joshua Callihan, Rosalva Chavez, Jonya Blahut, Risa Guysi and Holly Clarke.
The incoming team will work to further improve the device. Possible areas for refinement including scaling it up so that it could be used with rider lawnmowers and develop a way to insulate it.