|Transportation is the leading source for energy-related CO2 emissions.|
US energy-related emissions of CO2 rose 0.1% from 2004 to 2005, increasing from 5,903 million metric tons (MMTCO2) to 5,909 MMTCO2 in 2005, according to an early estimate from the US Energy Information Administration.
Emissions from petroleum accounted for 43.75% of total energy-related CO2 emissions in 2005. Although total emissions from petroleum fell 0.1%, (while emissions from coal increased by 1.4%) emissions from transportation edged up by 0.2% in 2005.
|Average fleet fuel economy, passenger cars and light-duty trucks. Source: EIA|
Declines in emissions from gasoline and jet fuel were offset by increases in distillate and residual fuel emissions.
In 1999, transportation-related CO2 emissions overtook industrial emissions and remain the largest source of energy-related CO2. Between 1990 and 2005, transportation CO2 emissions grew 23.4% (1.4% per year) and accounted for 32.8% of all energy-related CO2 emissions in 2005 (1,937 MMTCO2).
Separately, Environmental Defense released a new report—Global Warming on the Road—that concludes that US cars and light trucks are responsible for 45% of the CO2 emitted by automobiles around the world, even though America’s vehicles represent just 30% of the nearly 700 million cars in use worldwide.
The US share of CO2 emissions is disproportionately higher because American vehicles are driven more each year and on average burn more fuel than cars in other countries.
|Automakers vs. power companies. Click to enlarge.|
The cars and light trucks from each of the Big Three automakers—GM, Ford, and DaimlerChrysler—emit more carbon dioxide than the nation’s largest electric utility, American Electric Power (AEP), with its nearly 60 large coal-fired power plants and 36,000 megawatts of generating capacity, according to the report.
The report details, by automaker and vehicle type, the greenhouse gas contributions from the auto sector.
Surprisingly, given the popularity of SUVs, small cars (compacts and subcompacts) still accounted for the greatest portion of carbon emitted as of 2004 (25%)—a testament to how long today’s vehicles remain on the road. SUVs—with a 21% carbon share in the entire fleet and a 34% carbon share among new vehicles only—are close to moving into first place.
The report examines the three factors behind greenhouse gas emissions from automobiles: amount of driving, fuel economy, and the carbon content of motor fuel.
Reducing global warming on the road is a shared responsibility. By underscoring the magnitude of emissions from America’s automobiles, this report shows that all actors—automakers, fuel providers, consumers, and various levels of government—can help solve the problem by addressing those aspects of CO2 emissions they can control.—John DeCicco, author of the report and senior fellow at Environmental Defense