The White House wants to cut U.S. greenhouse gas (GHG) emissions by 80 percent by 2050, but the goal raises questions about one of the greatest sources of those pollutants, light-duty vehicles (LDVs). The Energy Department's National Renewable Energy Laboratory (NREL) has taken a close look at what specific combination of measures national experts have determined is needed to slash LDV emissions from 1,514 million metric tons (MMTs) to 303 MMTs of carbon dioxide (CO2) per year and meet this larger emissions-reduction goal.