By Aaron Stone

Despite continuing technological advancements and ongoing efforts of automakers to limit carbon dioxide emissions and improve fuel economy, only seven of the 13 largest manufacturers decreased emissions from MY 2015 to MY 2016, with just five improving fuel economy during the same period.

These findings are part of a new report from the U.S. Environmental Protection Agency (EPA), entitled “The Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975-2017.”

The report, published annually, claims to be the authoritative reference for CO2 emissions, fuel economy and power-train technology trends for new personal vehicles in the United States and references data collected and maintained by the U.S. EPA and the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA), since 1975.

The U.S. EPA report acknowledges Japanese carmaker Mazda as the star performer of MY 2016, exhibiting both the lowest fleetwide average adjusted emissions and the highest adjusted fuel economy performance. South Korea’s Hyundai is the big improver from a year earlier, achieving adjusted fuel economy of 28.8 mpg (a 1.3 mpg increase) and adjusted CO2 of 309 g/mi (down 15 g/mi). Conversely, Fiat-Chrysler delivered the highest CO2 emissions and lowest fuel economy data during the sample period, though it is important to note both Fiat-Chrysler and Volkswagen are listed separately in select data due to ongoing investigations and/or corrective actions. Fiat-Chrysler is an Italian-American corporation and currently the world’s eighth largest automaker.

Four manufacturers in the report demonstrated an increase in average adjusted CO2 emissions in MY 2016 from a year earlier — Honda, Nissan, BMW and Fiat Chrysler. While the authors conceded increases in truck share have impacted overall values, they also emphasized that frontrunners Mazda and Kia, which is part of the Hyundai Group, both improved overall fuel economy despite significant increases in truck share.

On the face of it, the EPA review sounds damning of the recent performance of some automakers, however there is no need for undue alarm. Though MY 2017 statistics will not be confirmed until next year’s report — preliminary data from MY 2017 suggests nearly all manufacturers will improve as they continue to adopt a diverse range of technology approaches to achieve efficiency targets.

The release of the January 2018 report high-lighted the snowballing popularity of Gasoline Direct Injection (GDI) engines, the authors projecting they will be used by more than half of vehicles in MY 2017. Many manufacturers are nearing 100% adoption of GDI engines, case in point — Mazda will utilize GDI engines exclusively in MY 2017. BMW, Mercedes, Volkswagen and Ford are championing the use of turbochargers, often used in conjunction with GDI engines, with market share to exceed 25% in MY 2017.

The research claims almost a quarter of MY 2017 vehicles will leverage transmissions with seven or more speeds, supported predominantly by Mercedes, BMW and Fiat-Chrysler. An additional 24% will rely on continuously variable transmissions (CVT), the favoured option of Subaru, Nissan and Honda. The report also concludes that German luxury carmakers Mercedes and BMW are the leading manufacturers of non-hybrid stop/start, while GM and Honda are utilizing cylinder deactivation the most.

Encouragingly, 26% of MY 2017 vehicles are likely to already meet or exceed MY 2020 CO2 emissions targets, which accounts for approximately 4.5 million vehicles per year in current sales.