Average fuel economy for light-duty vehicles sold in the U.S. reached a record high, and carbon dioxide emissions have reached a record low for model-year 2018, according to a report released by the Environmental Protection Agency. The average real-world carbon dioxide emission rate fall by 4 grams per mile to 353 g/mile, while fuel economy increased by 0.2 miles per gallon to 25.1 mpg.
Since 2004, CO2 emissions have decreased 23%, and fuel economy has increased 30%, or 5.8 mpg. Over that time, CO2 emissions and fuel economy have improved in 12 out of 14 years and have repeatedly achieved new records.
Preliminary data suggests further improvements in model-year 2019 — with carbon dioxide emissions expected to fall 6 g/mi to 346 g/mi and fuel economy projected to increase 0.4 mpg to 25.5 mpg. These are based on manufacturer projections rather than real-world data.
Tesla, since it only produces electric vehicles, had the lowest tailpipe CO2 emissions at 0 g/mi and the highest fuel economy at 113.7 mpge of all the large manufacturers in MY-2018. Of the remaining manufacturers, Honda had the lowest CO2 emissions and highest fuel economy.
Car and truck SUVs captured a record high 46% of market share in MY-2018. Truck SUVs improved fuel economy by 0.8 mpg and CO2 emissions by 14 g/mile, while car SUVs improved fuel economy by 1.2 mpg and CO2 emissions by 15 g/mile. Sedans, making up 37% of the market, increased fuel economy by 0.6 mpg.