The Obama administration made the latest in a series of moves to address climate change Friday, proposing to hike the fuel economy standards for heavy-duty trucks like tractor-trailers, delivery trucks and school buses. The proposed rule from the EPA would boost fuel efficiency for trucks, requiring ambitious improvements in post-2018 model years. Heavy-duty vehicles make up a small portion of the U.S. fleet but contribute an outsized portion of transportation-related greenhouse gas emissions.
