This study undertakes an investigation of the effect of battery charge balance in hybrid electric vehicles (HEVs) on EPA fuel economy label values. EPA's updated method was fully implemented in 2011 and uses equations which weight the contributions of fuel consumption results from multiple dynamometer tests to synthesize city and highway estimates that reflect average U.S. driving patterns. For the US06 and UDDS cycles, the test results used in the computation come from individual phases within the overall certification driving cycles. This methodology causes additional complexities for hybrid vehicles, because although they are required to be charge-balanced over the course of a full drive cycle, they may have net charge or discharge within the individual phases. As a result, the fuel consumption value used in the label value calculation can be skewed.
What happens if you buy an electric car and at some point in your ownership have to replace the battery? In this episode of Eye on Engineering, Editor-In-Chief Lindsay Brooke looks at the cost of replacing the BMW i3's battery. SAE Eye on Engineering also airs Monday mornings on WJR 760 AM Detroit's Paul W. Smith Show. Access archived episodes of SAE Eye on Engineering.
While the White House proposes to relax U.S. vehicle emission standards, in Europe theres no such talk. In this episode of SAE Eye on Engineering, Editor-In-Chief Lindsay Brooke looks at Mercedes race to meet tighter tailpipe regulations coming in 2021. SAE Eye on Engineering also airs Monday mornings on WJR 760 AM Detroit's Paul W. Smith Show. Access archived episodes of SAE Eye on Engineering.