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Smoked Out

Terp Invention Unmasks VW Emissions Cheating

By Chris Carroll


Photo Illustration by Steffanie Espat

Photo Illustration by Steffanie Espat

Volkswagen’s far-reaching plot to cheat on its vehicle emissions tests was exposed last fall by a device created decades ago by a Terp.

As he supervised emissions testing at the Environmental Protection Agency’s Virginia Testing Laboratory in the mid-1990s, Leo Breton M.S. ’90 couldn’t help but wonder if putting cars on rollers with professional drivers in a climate-controlled facility was a valid simulation of actual driving. So he went to work.

“No one was asking me to do it. There was no known reason to do it,” he says. “I invented it because I wanted to see what the emissions are in the real world.”

His 1995 solution was the Real-time, On-road, Vehicle Emissions Reporter (ROVER). It included a flow meter placed on the car’s tailpipe and other testing gear in the back seat to provide real-time accounting of emissions as a car navigates actual roads.

It confirmed his hunch: Emissions tests of the day underestimated emissions across the board while overestimating fuel economy.

His results helped the EPA improve regular emissions testing — and gave the agency the ability to detect when manufacturers were manipulating the computers that increasingly controlled every aspect of vehicle operations. Breton himself declines to talk about past cases, saying manufacturers have settled the issues and moved on, but old news reports illustrate ROVER’s value to regulators.

In 1998, the invention showed that manufacturers of heavy truck engines were employing operating strategies that EPA labeled “defeat devices” — software to change the way the trucks’ diesel engines ran while undergoing testing to cut emissions of nitrogen oxide, a chemical harmful to human health. The EPA alleged that when the truck computers sensed the test was over, they switched back, resulting in more fuel-efficient but dirtier operations. Breton’s device, however, defeats defeat devices because it can’t be detected by vehicles in real-world testing.

That case resulted in a $1 billion settlement and changes in how nitrogen oxide emissions are measured, as well as requirements for manufacturers to speed up the introduction of engines with additional emissions control hardware. In another case, General Motors paid a $40 million fine after the EPA used the equipment to show that flipping on the climate control system in some Cadillacs caused an increase in carbon monoxide emissions.

In 2001, however, the EPA closed the Virginia lab and stopped testing cars with the ROVER system, as reported by The Washington Post. Critics say that left the door open for manufacturers to again deploy defeat devices.

The Volkswagen scandal was revealed after investigators from a clean-air group, the International Council on Clean Transportation, tested cars in Europe and the United States using a commercial version of Breton’s invention. When hooked up to laboratory testing equipment, Volkswagen diesel cars met stringent U.S. requirements. When tested on the road, however, nitrogen oxide output rose up to 40-fold.

Breton wasn’t involved with that testing. He long ago left the EPA and now focuses on improving fuel economy in the Vehicle Technologies Office at the U.S. Department of Energy. (He still invents in his spare time, and is currently trying to market a “smart” stovetop that automatically controls the burners to save energy and increase convenience.)

But he’s happy his hunch 21 years ago helped reveal a cheating scandal Volkswagen admits encompassed 11 million vehicles worldwide manufactured since 2009. The company stopped selling the dirty vehicles, shook up its management and is facing a U.S. government lawsuit.

“You could say I was rather satisfied when I learned the testing that showed the emissions levels from those vehicles was based on the equipment I invented,” he says.

Maryland Today is produced by the Office of Marketing and Communications for the University of Maryland community on weekdays during the academic year, except for university holidays.