A new study from the International Council on Clean Transportation details the currently available options for achieving big reductions in greenhouse gas emissions and fuel use from an easy-to-overlook source: making semi-trailers more efficient.
Heavy duty vehicles account for roughly 20 percent of U.S. greenhouse gas emissions from transportation, and about 17 percent of transportation oil use, making them a key target of opportunity for both climate and energy policy. The Obama administration's climate action plan explicitly recognizes their importance: increasing fuel-economy standards for HDVs is the first step it identifies toward "building a 21st-century transportation sector."
There are numerous promising strategies for reducing fuel use and CO2 emissions from this part of the U.S. transportation sector. The ICCT study, "Trailer technologies for increased heavy duty vehicle efficiency," authored by Ben Sharpe, Nigel Clark and Dana Lowell, focuses on one: increasing the efficiency of semi-trailers on long-haul trucks, primarily by reducing aerodynamic drag, rolling resistance, and weight.
When the EPA and the National Highway Traffic Safety Administration were finalizing the first GHG and fuel-efficiency standards for medium and heavy duty vehicles in 2010–2011, the agencies acknowledged the substantial fuel savings to be achieved from improvements to trailers. Nevertheless, they declined to include trailers in that "Phase 1" rule, citing time constraints and the need to reach out to the industry.
Phase 2—which, the administration's climate plan signals, is soon to begin—presents an opportunity to take the important next step of integrating trailers into that pioneering regulation. A combination of off-the-shelf technologies for reducing aerodynamic drag, rolling resistance and trailer empty weight can reduce overall tractor-trailer fuel consumption by 10 percent or more—a significant gain, in view of the fact that tractor-trailers account for roughly two-thirds of fuel use and GHG emissions from the entire heavy duty vehicle sector.
Bringing trailers into the U.S. medium and heavy duty vehicle standards will significantly improve the fuel savings and climate benefits of the Phase 2 regulation. This study outlines the technology options and offers some specific recommendations for that upcoming rulemaking.
The report is available from the ICCT website, http://theicct.org/heavy-duty-vehicles.