Abstract
This paper investigates the potential for making deep cuts in US transportation greenhouse gas (GHG) emissions in the long-term (50-80% below 1990 levels by 2050). Scenarios are used to envision how such a significant decarbonization might be achieved through the application of advanced vehicle technologies and fuels, and various options for behavioral change. A Kaya framework that decomposes GHG emissions into the product of four major drivers is used to analyze emissions and mitigation options. In contrast to most previous studies, a relatively simple, easily adaptable modeling methodology is used which can incorporate insights from other modeling studies and organize them in a way that is easy for policymakers to understand. Also, a wider range of transportation subsectors is considered here-light- and heavy-duty vehicles, aviation, rail, marine, agriculture, off-road, and construction. This analysis investigates scenarios with multiple options (increased efficiency, lower-carbon fuels, and travel demand management) across the various subsectors and confirms the notion that there are no "silver bullet" strategies for making deep cuts in transport GHGs. If substantial emission reductions are to be made, considerable action is needed on all fronts, and no subsectors can be ignored. Light-duty vehicles offer the greatest potential for emission reductions; however, while deep reductions in other subsectors are also possible, there are more limitations in the types of fuels and propulsion systems that can be used. In all cases travel demand management strategies are critical; deep emission cuts will not likely be possible without slowing growth in travel demand across all modes. Even though these scenarios represent only a small subset of the potential futures in which deep reductions might be achieved, they provide a sense of the magnitude of changes required in our transportation system and the need for early and aggressive action if long-term targets are to be met.
| Original language | English |
|---|---|
| Pages (from-to) | 5580-5596 |
| Number of pages | 17 |
| Journal | Energy Policy |
| Volume | 37 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 2009 |
| Externally published | Yes |
Funding
The authors would like to thank the Sustainable Transportation Energy Pathways (STEPS) Program at the University of California-Davis, Institute of Transportation Studies for funding. Gratitude is particularly expressed to Joan Ogden, Daniel Sperling, and David Greene for extensive review and helpful comments on this paper and to numerous others for input on this project, especially Ryan McCarthy and Wayne Leighty. We are also grateful to two anonymous reviewers who spent a considerable amount of time, helping us to significantly improve this paper. In addition, the authors would like to acknowledge the participants of the 2007 Asilomar Conference on climate change and transportation, whose shared wisdom and dialogue spawned this research effort. The views and opinions expressed in this paper are those of the authors alone and do not necessarily represent those of any sponsoring organization or outside reviewer.
| Funders | Funder number |
|---|---|
| Institute of Transportation Studies | |
| University of California-Davis |
Keywords
- Alternative fuel
- Efficiency
- Emissions reduction
