The average lifetime carbon emissions for Nissan's 2005 fleet rose 9.2 percent from 1990 as the company added more light trucks with poorer fuel economy, Environmental Defense, an advocacy group based in Washington, said today. Toyota Motor Corp.'s average emissions rate fell 3 percent during that span.
The report comes five days before Congress returns to session, and lawmakers such as Representative John Dingell have said they will propose laws to reduce U.S. carbon emissions. Cars and light trucks account for about 20 percent of the country's carbon output, which contributes to global warming.
``Market shifts to date fall far short of what would be needed to truly address global warming,'' wrote John DeCicco, the study's lead author. ``New policies will be needed to significantly limit automobile carbon burdens.''
DaimlerChrysler AG's fleet had the second-highest increase in emissions during those 15 years at 4.8 percent, followed by Honda Motor Co.'s 4.4 percent and Ford Motor Co.'s 4.3 percent. General Motors Corp.'s average rose 3 percent.
``Since the end of this report in 2005, we have added the subcompact Nissan Versa, Altima Hybrid and flex-fuel-capable trucks,'' Nissan spokeswoman Jeannine Ginivan said in an e-mail. She said Nissan ``has committed to a comprehensive plan to reduce carbon-dioxide emissions and to improve fuel economy.''
Hybrids, Flex-Fuel Cars
Hybrid vehicles reduce emissions by generating some power from an electric motor, using less fuel for each mile traveled. Flex-fuel vehicles can run on conventional gasoline or E85, a blend containing 85 percent ethanol.
The rising emissions rates in the U.S. stem from an increase in demand for pickup trucks, minivans and sport-utility vehicles, which generally get poorer fuel economy than passenger cars, the study said. An increase in driving and the number of the cars on the road has also pushed up total emissions.
Toyota's shrinking emissions rate is due to its hybrid Prius and improving fuel economy in its conventional gasoline cars, such as the Corolla sedan, DeCicco said at a news conference today.
