2011 edition of EPA Fuel Economy Trends report shows several advanced powertrain technologies making significant gains
|Light duty vehicle characteristics for seven model years. Data: EPA. Click to enlarge.|
The average fuel efficiency for new cars and light duty trucks has increased while the average carbon dioxide (CO2) emissions continue to decrease for the seventh consecutive year, according to the 2011 edition of the US Environmental Protection Agency’s (EPA) annual report, “Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 Through 2011.”
The report highlights that several advanced powertrain technologies are making significant inroads into the mainstream market. In terms of market share, gasoline direct injection doubled in MY 2010 (from 4.2% to 8.3%) and is projected to triple from MY 2009-2011 (to 13.7%); turbocharging is projected to double in MY 2011 (from 3.5% to 7.4%); cylinder deactivation is projected to nearly double in MY 2011 (from 6.4% to 11.1%); and both 6-speed and 7-speed transmissions approximately doubled from MY 2009-2011 (from 24.7% to 52.4% and from 2.6% to 4.9%, respectively).
Conventional gasoline vehicles continue to account for more than 95% of all light-duty vehicles. While engine size has been decreasing slightly in recent years, overall engine horsepower has continued to increase, with the notable exception of MY 2009. Nearly all engines now have multiple valves (approximately 85%) and variable valve timing (projected to approach 95% in MY 2011).
Hybrids of all types are projected to grow slightly to 4.0% share for MY 2011, up from 3.8% for MY 2010, with almost a doubling from MY 2009 (2.3%). Fuel economy improvements for the hybrid vehicles vary considerably from 5-10% for the larger, luxury hybrid vehicles to more than 40%.
Light-duty diesel are seen dropping share slightly to 0.6% for MY2011, down from 0.7% in MY 2010, but up from 0.5% in MY 2009. Fuel economy improvements for diesels range from 15% to 30% relative to gasoline counterparts.
Final MY 2010 data in the report are are based on formal end-of-year CAFE reports submitted by automakers to EPA and will not change. The preliminary MY 2011 data in the report are based on confidential pre-model year production volume projections provided to EPA by automakers during MY 2010 for the fuel economy label program.
|Data: EPA. Click to enlarge.|
Other highlights in the report include:
MY 2010 had the lowest CO2 emission rate and highest fuel economy since the database began in 1975. While year-to-year changes often receive the most public attention, the report notes, the greatest value of the historical trends database is the identification and documentation of long-term trends.
Since 1975, overall new light-duty vehicle CO2 emissions have moved through four phases: 1) a rapid decrease from MY 1975 through MY 1981; 2) a slower decrease until reaching a valley in MY 1987; 3) a gradual increase until MY 2004; and 4) a decrease for the seven years beginning in MY 2005, with the largest decrease in MY 2009.
From MY 2004 to MY 2010, CO2 emissions decreased by 67 g/mi (15%), and fuel economy increased by 3.3 mpg (17%). Prior to MY 2009, the previous records for lowest CO2 emissions and highest fuel economy were in MY 1987. Compared to MY 1987, MY 2010 CO2 emissions were 11 g/mi (3%) lower, and fuel economy was 0.6 mpg (3%) higher.MY 2010 adjusted composite CO2 emissions were 394 g/mi, a record low for the post-1975 database and a 3 g/mi decrease relative to MY 2009. MY 2010 adjusted composite fuel economy was 22.6 mpg (10.4 L/100 km), an all-time high since the database began in 1975, and 0.2 mpg higher than in MY 2009. Preliminary MY 2011 values are 391 g/mi CO2 emissions and 22.8 mpg (10.3 L/100 km) fuel economy, reflecting slight improvements over MY 2010.
MY 2010 truck market share increased by 5% compared to MY 2009, but is at the second lowest level since 1996. EPA made two changes to the database this year that affect truck market share. Most small, 2 wheel drive SUVs from MY 1975-2011 have been reclassified from trucks to cars; this lowers the absolute truck share, particularly since the mid-1980s when SUV sales began to increase rapidly. EPA cautions that truck share values in the current report should not be compared to those in past versions of the report.
For example, for MY 2010 data in the 2011 report, nearly 1.1 million vehicles are reclassified from trucks to cars, representing a 10% absolute change in both the car and truck production share. The second change is that, for the first time, the preliminary data for MY 2011 include MDPVs (medium-duty personal vehicles). EPA does not have data for MDPVs for MY 1975-2010, so there is a small discontinuity in the database beginning in MY 2011.
With those adjustments, light trucks, which include SUVs, minivans/vans, and pickup trucks, accounted for 36% of all light-duty vehicle sales in MY 2010. This represents a 5% increase over MY 2009, but MY 2009 truck share was 8% lower than MY 2008. Truck market share is now at the second lowest level since MY 1996 and 9% lower than the peak in MY 2004. The MY 2011 light truck market share is projected to be 38%, based on pre-model year production projections by automakers.
MY 2010 weight and power increased from MY 2009, but decreased relative to MY 2008. MY 2010 vehicle weight averaged 4,002 pounds (1,815 kg), an increase of 85 pounds (38.6 kg) compared to MY 2009, but the second lowest average weight since MY 2004. The average car and truck weight both increased by about 25 pounds (11.3 kg) each, and the remaining difference was due to higher truck market share.
In MY 2010, the average vehicle power was 214 horsepower, an increase of 6 horsepower since MY 2009, but lower than in MY 2007-2008. Car power increased slightly and truck power was unchanged, so the primary factor in increasing the overall power level was higher truck market share. Estimated MY 2010 0-to-60 acceleration time decreased slightly to 9.6 seconds.
Most manufacturers increased fuel economy in MY 2010, resulting in lower CO2 emission rates. In MY 2010, the last year for which EPA has final production data, Hyundai had the lowest fleet-wide adjusted composite CO2 emissions performance, followed very closely by Kia and then Toyota. Hyundai and Kia tied for the highest fleet-wide adjusted composite fuel economy value.
Daimler had the highest CO2 emissions (and lowest fuel economy), followed by Chrysler and Ford. Kia had the biggest improvement in adjusted CO2 (and fuel economy) performance from MY 2009 to MY 2010, with a 37 g/mi reduction in fleet-wide CO2 emissions (and 2.8 mpg fuel economy improvement), followed by Hyundai (26 g/mi reduction in CO2 emissions) and Mazda (19 g/mi reduction in CO2 emissions).
Preliminary MY 2011 values suggest that 11 of the 13 manufacturers will improve further in MY 2011, though these projections are uncertain and EPA will not have final data until next year’s report.