By Ryan Beene, Crain News Service
WASHINGTON (Feb. 24, 2015) — The U.S. Environmental Protection Association (EPA) issued on Feb. 23 updated procedures for a critical part of fuel economy testing that some auto makers have struggled with in the last two years.
The update covers how auto makers should calculate road load values in coast down tests, which measure the rolling resistance and aerodynamic drag of vehicles as they glide from 70 mph to a stop on a straight, flat track. Those values are used to program dynamometers the auto makers use to calculate fuel economy ratings using the EPA's test cycle.
The update clarifies how auto makers should prep vehicles for coast down testing and updates the test to monitor road load levels over a broader range of speed during the test. Chris Grundler, director of the EPA's Office of Transportation Air Quality, said the changes will help ensure the accuracy of fuel economy labels, and clarify how the EPA expects the tests to be done.
“It will be more accurate,” Mr. Grundler said. “Both the EPA and the auto makers have a common cause to make sure that customers are getting the best information.”