White House proposes greater fuel efficiency for trucks to cut emissions

The Obama administration on Friday announced plans to tighten fuel-economy standards for heavy trucks, buses and vans, taking aim at a transportation sector that contributes a quarter of the greenhouse-gas pollution emitted by U.S. vehicles each year.

The proposed regulations would require truck manufacturers to dramatically improve engine efficiency over the next 12 years in an effort to cut down on fuel consumption and reduce the carbon-dioxide emissions blamed for global warming, administration officials said.