The National Research Council weighs in on heavy truck trailers

Last Thursday, the National Research Council published its interim report on technologies and strategies for reducing the fuel consumption and greenhouse gases (GHGs) from heavy-duty vehicles in the U.S. This is part of a longer study, scheduled to be completed in 2016 and designed to be a important input for the Environmental Protection Agency and the National Highway Traffic Safety Administration as they craft the Phase II regulation on fuel efficiency and GHG emissions from trucks and buses over the course of the next two years. (In February, President Obama announced plans for the Phase II regulatory proposal to be published by spring of 2015, with a final rule published roughly a year later.) The report weighs in on a number of topics relevant to the Phase II rulemaking, including technology potential for tractor-trailers and the other commercial vehicle segments, potential regulatory structure and test procedures, and the role of natural gas vehicles.

One very important detail in the Phase II rulemaking that we at the ICCT have focused on will be whether and how to incorporate truck trailers into the rule (see our recent white papers here and here and here, as well as this consultant report). So we’re glad to see that the NRC committee devoted an entire chapter of the six-chapter report to a review of options for reducing the energy use associated with trailers. Specifically, the report addresses trailer technology potential, current levels of fuel-saving technology adoption, costs, testing and certification, market barriers, and policy considerations.

And we’re also glad to note that the report’s conclusions are congruent with our own. Some of the highlights below.

On regulating trailers:

The omission of trailer regulations has led to suboptimal regulatory constructs when considering the combined tractor-trailer. The culture change in the tractor-van trailer fleet technical community has progressed but has done so absent clear signals on the cost effectiveness of integrating trailers into the total vehicle. Separate regulation of trailers for fuel efficiency will have the beneficial effect of beginning integration of trailer design with the tractor for improved aerodynamic performance, lower tare weight, and a requirement for low-rolling-resistance tires. (page 1-8)

On trailer technology’s efficiency potential:

Trailer manufacturers indicate a high customer interest in side-skirt-equipped pup trailers (dual, 28 ft trailers). Several manufacturers reported a fuel use reduction of 7 to 9 percent for pups with side skirts (compared to 5 to 7 percent for advanced sides skirts used on 53+ ft van trailers). (page 6-17)

On applicable trailer types:

NHTSA, in coordination with EPA, should adopt a regulation requiring that all new, 53 ft and longer dry van and refrigerated van trailers meet performance standards that will reduce their fuel consumption and CO2 emissions. (Recommendation 6.1, page 6-25)

NHTSA, in coordination with EPA, should determine whether it would be practical and cost effective to include with the regulation of van trailers the regulation of other types of trailers such as pups, flatbeds and container carriers, as doing so could substantially increase overall fuel savings. (Recommendation 6.2, page 6-26)

With regard to “pup” trailers (i.e. shorter trailers generally between 24 and 40 feet) and non-box trailers, the report notes that there are aerodynamic, tire rolling resistance, and weight reduction technologies that can provide fuel savings, but stops short of recommending that pups and non-box trailers be regulated along with 53-ft. or longer dry and refrigerated trailers. This is in contrast to many other stakeholders, who believe that, at a minimum, the EPA and NHTSA would be on sound footing to enact standards that promote improved tire efficiency across all trailer lengths and categories.

Altogether, this report from the NRC emphasized the fuel-saving and GHG reduction opportunities presented by trailers and the need to include them in the Phase II program to maximize cost-effective improvements for tractor-trailers. If the agencies do look to enact standards for tractors and trailers, trailer technologies might contribute up to half of the required new efficiency improvements from Phase II.

In a paper to be published this spring, we will investigate various regulatory scenarios, some timing options for trailer requirements, the estimated incremental technology costs, and the fuel-saving benefits associated with bringing trailers into the next regulatory phase. That paper will illuminate some of the research and data gaps that can be shored up over the next year or so, and synthesize the findings of our previous papers to explore the net benefits of various trailer regulation approaches. All of this will, we hope, help in developing as strong and sound a regulation for trailers as possible.