Consequences of Weakening 2022–2025 Corporate Average Fuel Economy Standards

It is critical to consider the potential consequences of weakening Corporate Average Fuel Economy (CAFE) standards for Light-Duty Vehicle (LDV) model years 2022-2025. In particular, weak standards for 2022-2025 will make it much more difficult to reduce U.S. greenhouse emissions to a level compatible with two degrees Celsius of global warming. The existing literature does describe the impacts of weakening these medium-term CAFE standards in relative terms on the long-term average fuel economy of the LDV fleet. In addition, the literature does not provide specific targets for CAFE in 2050 that would be compatible with a two-degree scenario under either existing or weakened 2022-2025 CAFE standards. In this paper, fuel economy trajectories for both scenarios are explored and the consequences of forgoing progress on U.S. LDV climate policy are discussed using a model of the U.S. LDV Fleet. With the U.S. LDV Fleet Model, the model shows that a very aggressive CAFE target is necessary in 2050 in order for the LDV fleet to contribute proportionally to the requisite U.S.-wide reductions for a two-degree scenario. The necessary 2050 standard given the current 2025 CAFE standard is 220 MPG greenhouse gas-equivalent (MPGghg), and the necessary 2050 standard required under Weak CAFE standard is 330 MPGghg. These results show that the average new vehicle in 2050 will have to achieve 110 additional MPG ghg between 2025 and 2050 for the sake of avoiding 7 MPG ghg fuel economy increase between 2021 and 2025, if the U.S. is to implement an LDV policy compatible with a two-degree scenario.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References;
  • Pagination: 6p

Subject/Index Terms

Filing Info

  • Accession Number: 01661628
  • Record Type: Publication
  • Report/Paper Numbers: 18-04865
  • Files: TRIS, TRB, ATRI
  • Created Date: Jan 8 2018 11:12AM