

Photo by Thomas A. Ferrara/Newsday

President Obama will announce Tuesday that the federal government will further tighten fuel efficiency for medium- and heavy-duty trucks, according to a White House official, as part of the president's ongoing effort to use his executive authority to address climate change.

Obama's directive to the Environmental Protection Agency and the Department of Transportation, which he will announce at the Safeway distribution center in Upper Marlboro, Md., marks the second time he has mandated a cut in fuel consumption and carbon emissions from larger trucks. This category, which encompasses all vehicles weighing more than 8,500 pounds, ranges from large pick-up trucks and school buses to massive 18-wheel tractor-trailers.

An earlier rule, finalized in September 2011, improved the fleet's fuel efficiency by between 9 percent and 23 percent, with the largest trucks experiencing the largest reductions. The Obama administration estimates that those standards, which applied to the model years 2014 through 2018, cost the industry roughly $8 billion but would save truck users about $50 billion in fuel costs over the lifetimes of the vehicles.

The new greenhouse gas standards will become final by March 2016, according to a fact sheet provided by the White House, and apply to subsequent model years. The White House did not specify what reduction targets it hoped to achieve through the new rule.

Unlike some of the president's greenhouse gas proposals, which have prompted a backlash from the affected industries, many truck suppliers have embraced the idea of reducing carbon emissions.

"The juxtaposition between the positions of the motor vehicle and power sectors on the president's climate action plan is startling," S. William Becker, executive director of the National Association of Clean Air Agencies, wrote in an e-mail. "While truck manufacturers are lining up behind the plan pledging their support and cooperation, most of the power plant industry is fighting it tooth and nail."

In 2011 transportation accounted for about 28 percent of the nation's greenhouse gas emissions, second only to the electricity sector. Heavy-duty vehicles represent a major opportunity to cut transportation oil use and carbon pollution.

In 2010, heavy-duty vehicles represented just four percent of registered vehicles on the road in the U.S., but they accounted for roughly a quarter of the transport sector's greenhouse gas emissions. They are the second-largest source of greenhouse gas emissions within transportation, after cars and light-trucks.

Obama is unveiling the proposal at Safeway, said a White House official who asked not to be identified because the event had not taken place, because the company has invested in more efficient trucks and trailers, through both better aerodynamics and more efficient tires.

"What the president plans is a classic example of using executive power to make further reductions in greenhouse gases from one of the most notorious emission sources," Frank O'Donnell, president of the advocacy group Clean Air Watch, wrote in an e-mail.