The United States Environmental Protection Agency and the Department of Transportation are deliberating on a second phase of regulations to increase the efficiency of heavy-duty vehicles. One of the most substantial policy questions in the rulemaking is whether trailers of Class 7 and 8 combination tractor-trailers will be regulated and, if so, how. That decision hinges on technology availability and the associated costs and benefits of regulating trailers. This paper aims to inform the agencies’ deliberations on these important questions.
The paper builds on recent ICCT research on the integration of commercial trailers into the regulations of heavy-duty vehicle fuel consumption and greenhouse gas (GHG) emissions (see here and here and here). It finds that the Phase 2 regulation presents an opportunity to capture substantial and highly cost-effective efficiency gains offered by trailer technology improvements. The analysis considers three scenarios for increased technology penetration in new trailers. An “advanced technology” scenario, which represents the highest penetration of advanced trailer efficiency packages, indicates that there is the potential to achieve GHG-emission savings of up to 19 million metric tons of CO2 and oil savings of 149 million barrels per year in 2040. Under this scenario, the benefit-to-cost ratio of advanced trailer technologies is 11-to-1 and the average payback period for end users is roughly two years.
These findings point toward a Phase 2 heavy-duty vehicle regulatory program for the United States and Canada that more comprehensively promotes these known cost-effective trailer technologies. The ICCT recommends integration of trailers into the Phase 2 U.S. heavy-duty vehicle regulatory program, with emphasis on box trailers but inclusion of other types as well. Beyond these results from this analysis, we recommend that as they deliberate on this rulemaking the EPA, NHTSA, and other stakeholders continue to investigate trailer activity rates and levels of technology adoption--especially for "pup" and non-box trailers--as well as complementary policy measures.