U.S. Emits Nearly Half World's Automotive Carbon Dioxide

WASHINGTON, DC, June 28, 2006 (ENS) - The United States has five percent of the world's population and 30 percent of the world's automobiles, but the country contributes 45 percent of the world's automotive emissions of the greenhouse gas carbon dioxide, according to a report released today by the advocacy group Environmental Defense.

Automobile exhaust has weight. The report estimates that two mid-sized vehicles emit more than nine metric tons of carbon dioxide (CO2) a year into the atmosphere, where it blankets the Earth, trapping the Sun's heat close to the planet.

The authors present the image of a coal train that stretches 55,000 miles, long enough to circle the globe twice, carrying 314 million metric tons of carbon - the amount of CO2 emitted by U.S. cars and trucks in the year 2004.

"Cutting greenhouse gas emissions from U.S. automobiles will be critical to any strategy for slowing global warming," said John DeCicco, author of the report and senior fellow at Environmental Defense.

"To address global warming, we'll need a clear picture of what sources are contributing to the problem," he said. "This report details, by automaker and vehicle type, the greenhouse gas contributions from America's auto sector, for the first time."


American vehicle traffic contributes 45 percent of the world's automotive carbon dioxide load. (Photo courtesy Federal Highway Administration)
The report examines the three factors behind greenhouse gas emissions from automobiles - amount of driving, fuel economy, and the carbon content of motor fuel.

The authors found that U.S. cars and light trucks were driven 2.6 trillion miles in 2004 with an average fuel economy of 19.6 miles per gallon, and they conclude that American vehicles are driven more each year and on average burn more fuel than cars in other countries.

Small cars - compacts, subcompacts and two seaters - were once the most popular type of car sold, and they accounted for the greatest portion of carbon emitted as of 2004 - showing how long today's vehicles remain on the road.

The report says gas-guzzling SUVs will soon be the main source of CO2 emissions from U.S. autos, because in 2002 they overtook small cars in market share.

In terms of usage, the U.S. light vehicle stock now has a "half-life" of roughly eight years - that is, 50 percent of vehicles are replaced within that time.

It takes 16 years for the American automotive fleet to be 90 percent replaced in terms of the carbon emitted during driving, the authors found. "In short," they said, "the choices made regarding new vehicles influence emissions for many years to come."

In 2005, transportation-related carbon dioxide emissions, which account for about a third of total carbon dioxide emissions, increased by 0.2 percent, according to a report issued today by the U.S. Energy Department's Energy Information Administration.

Emissions related to gasoline demand decreased by 0.4 percent, emissions related to diesel fuel grew by 1.0 percent and jet fuel emissions decreased by 0.5 percent, the goverment report states.

"Fixing the global warming problem without making cars more efficient is like trying to fix a leaky roof without a hammer," said Environmental Defense President Fred Krupp. "The leading automakers must accept responsibility for becoming part of the solution."

The report states that the total CO2 emissions in 2004 from automobiles made by the three largest U.S. automakers - Ford, General Motors, and DaimlerChrysler - was comparable to the total emissions from the top 11 electric companies.

"Reducing global warming on the road is a shared responsibility," said DeCicco. "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."

Automakers are developing vehicles that offer lower emissions profiles. Ford announced that its Volvo environmental car program took home the gold at the Michelin Challenge Bibendum in Paris, earlier this month. The annual event showcases the latest technological advances in the field of environment-friendly vehicles.

The Bibendum attracted 2,500 participants, representing around 100 manufacturers, nongovernmental organizations and institutions. Participants competed in seven areas: acceleration, braking, slalom, noise, emissions, fuel efficiency, and carbon dioxide emissions.

Volvo debuted the Multi-Fuel Vehicle, a five-cylinder, 2.0-litre prototype car that can run on five different fuels. It operates on hythane (10 percent hydrogen and 90 percent methane), biomethane, natural gas, bioethanol E85 (85 percent bioethanol and 15 percent petrol) and gasoline.


Volvo's new Multi-Fuel car runs on five different fuels. (Photo courtesy Ford)
By running on pure renewable fuels like hydrogen, biomethane and bioethanol, Volvo says the Multi Fuel Vehicle makes a "negligible net contribution of fossil carbon dioxide."

"The whole car is optimized for high performance, driving on any of the five different fuels," said Mats Moren, project leader for engine development at Volvo Car Corporation. "It is a first step towards a hydrogen powered society."

In March, General Motors introduced the world's first hybrid vehicle with zero CO2 emissions. The Saab BioPower Hybrid Concept car displayed at the Stockholm Motor Show is a convertible that runs on bioethanol fuel and electric power.

The 260 hp (191 kW) 2.0-liter turbo BioPower engine and 53 kW electric motors allow the driver to achieve zero to 100 kph (60 mph) acceleration in just 6.9 seconds.

Jan Ake Jonsson, Saab Automobile's managing director said, "Although the exact hybrid application shown in this concept does not currently figure in our production plans, the project has been extremely valuable in helping us further our expertise. It shows how we could develop the sporty performance associated with Saab while using only renewable resources and saving energy overall."

DaimlerChrysler will be introducing its diesel-powered smart car to the U.S. market in 2008. The two-seater low emissions vehicle is fuel-efficient but it uses only petroleum diesel. The manufacturer says biodiesel fuel is not recommended.

To view the Environmental Defense report, "Global Warming on the Road," click here.