Research Proposal

Medium/Heavy-Duty Vehicle Emissions


Find out which vehicle classes make the biggest contribution to greenhouse gas emissions in order to test a hypothesis.

Early Findings

  • According to the EPA, the typical passenger vehicle emits 4.6 metric tons of carbon dioxide per year (based on fuel, fuel economy, and the number of miles driven each year).
  • “In addition to carbon dioxide (CO2), automobiles produce methane (CH4) and nitrous oxide (N2O) from the tailpipe and hydrofluorocarbon emissions from leaking air conditioners. The emissions of these gases are small in comparison to CO2; however, the impact of these emissions can be important because they have a higher global warming potential (GWP) than CO2.”
  • Greenhouse gas (GHG) emissions from transportation account for approximately 29% of the total GHG emissions in the United States.
  • SmartWay is a collaboration between the EPA and its partners in the freight transportation industry to improve supply chain efficiency and reduce GHG. Partners include FedEx, Schneider, Nike, IKEA, and the Home Depot, among others.
  • GHG emission regulations from a joint EPA and NHTSA effort were rolled out in August 2011. The regulations were set to “reduce CO2 emissions by about 270 million metric tons and save about 530 million barrels of oil over the life of vehicles built for the 2014 to 2018 model years, providing $49 billion in net program benefits.”
  • Phase II was set to begin in August 2016. This phase of the joint EPA/NHTSA was set to lower CO2 emissions by ~1.1 billion metric tons, save $170 billion on fuel costs for car owners, and reduce oil consumption by up to 2 billion barrels over the lifetime of vehicles sold under the program.
  • "However, in November 2017, a proposed rule to repeal the emissions requirements was issued noting that for heavy-duty glider vehicles, glider engines, and glider kits based on a proposed interpretation of the Clean Air Act (CAA) under which glider vehicles would be found not to constitute 'new motor vehicles' within the meaning of CAA section 216(3), glider engines would be found not to constitute 'new motor vehicle engines' within the meaning of CAA section 216(3), and glider kits would not be treated as 'incomplete' new motor vehicles. Under this proposed interpretation, EPA would lack the authority to regulate glider vehicles, glider engines, and glider kits under CAA section 202(a)(1)."
  • Glider vehicles are said to produce 55 times more diesel soot than new trucks.
  • GHG emissions for the EPA are currently reported up to the year 2014. The latest GHG emissions inventory written by the EPA was published in April 2016. That report is available here.
  • In 2014, GHG emissions in the United States totaled 6,870 million metric tons of CO2 equivalents. The emissions in 2014 are 9% below 2005 levels. However, others report that vehicle emissions are rising.
In addition to this public search, we scanned our proprietary research database of over 1 million sources and were unable to find any specific research reports that address your goals.
Prepared By
Amy R.
1720 assignments | 5.0