New CAFE standards announced recently by President Obama could potentially decrease fuel efficiency in fleet vehicles if regulators are not careful, according to a report in Fleet Owner.
President Obama recently announced new, tougher standards for the corporate average fuel economy (CAFE) standards in an effort to reduce carbon emissions among U.S. automobiles. However, these standards are based on miles-per-gallon measurements, a metric that is inappropriate for medium- and heavy-duty vehicles, according to the report.
While a partially loaded tractor-trailer will have a better mpg rating than one that is fully loaded, the difference does not accurately reflect the efficiency level of transporting goods, Fleet Owner reported, citing a report by the National Research Council (NRC). According to the NRC, a better metric for such vehicles is the amount of fuel consumed for every unit of payload. Otherwise, CAFE could favor half-loaded trailers that get better gas mileage, but result in less efficient transportation than a fully loaded trailer.
In order to arrive at metrics that accurately reflect energy efficiency ratings for a variety of vehicle types, The National Transportation Highway Safety Administration (NHTSA) will need to develop more complex calculations that vary depending on vehicle type, according to the report. That will require segmenting the market and developing multiple duty cycles with load-specific measurements.
One possible metric for highway trucks could be ton-miles per gallon, which would incorporate how far a truck is able to transport a ton on a single gallon of fuel.