https://www.nytimes.com/2017/03/03/us/politics/trump-vehicle-emissions-regulation.html
WASHINGTON The Trump administration is expected to begin rolling back stringent federal regulations on vehicle pollution that contributes to global warming, according to people familiar with the matter, essentially marking a U-turn to efforts to force the American auto industry to produce more electric cars.
The announcement which is expected as soon as Tuesday and will be made jointly by the Environmental Protection Agency administrator, Scott Pruitt, and the transportation secretary, Elaine L. Chao will immediately start to undo one of former President Barack Obamas most significant environmental legacies.
The regulatory rollback on vehicle pollution will relax restrictions on tailpipe emissions of carbon dioxide and will not require action by Congress. It will also have a major effect on the United States auto industry.
Under the Obama administrations vehicle fuel economy standards, American automakers were locked into nearly a decade of trying to design and build ever more sophisticated fuel-efficient vehicles, including electric and hybrid models. The nations largest auto companies told Mr. Trump last month that they found those technical requirements too burdensome.
On Feb. 21, a coalition of the 17 largest companies that sell cars in the United States sent two letters to Mr. Pruitt, asking him to revisit the tailpipe rules. They said it may be the single most important decision the E.P.A. has made in recent history.
They complained about the steep technical challenge posed by the stringent standard, noting that only about 3.5 percent of new vehicles are able to reach it. That even excludes some hybrid cars, plug-in electric cars and fuel cell vehicles, the automakers wrote. Even today, no conventional vehicle today meets that target.
The automakers estimated their industry would have to spend a staggering $200 billion between 2012 and 2025 to comply and said the tailpipe emissions rule was far more expensive for the industry than enforcing the Clean Power Plan.