The following article by Christopher Ingraham was posted on the Washington Post website August 2, 2018:
The Environmental Protection Agency on Thursday announced a plan to weaken fuel-economy standards put in place under the Obama administration.
The new plan would freeze standards at 2020 levels through the year 2025 and beyond. Under the Obama administration, automakers were required to reach a fleetwide average fuel economy for all cars and light trucks of 51.4 miles per gallon by 2025. The Trump administration’s proposal instead freezes that figure at its 2020 level of 36.9 miles per gallon.
But the EPA’s standards refer to testing under laboratory conditions, not the mileage we get when driving our cars on the road. To know how the new standards would affect real-world gas mileage, researchers need to take the further step of modeling how real-world use differs from laboratory conditions.