Today the Department of Transportation and the Environmental Protection Agency adopted the first fuel efficiency and greenhouse gas standards for heavy trucks and buses in the U.S., covering vehicles from super-duty pickups to tractor-trailers starting in model year 2014. ACEEE projects that the program will save 280,000 barrels of oil per day by 2030, roughly the amount the U.S. currently imports from Brazil. Fuel savings under the program will quickly pay back the upfront cost of the truck improvements. Buyers of tractor-trailers will get their investments back in under a year, and net lifetime savings will total tens of thousands of dollars per vehicle.
While the standards do not capture all the cost-effective fuel savings and emissions reductions available, getting a heavy-duty efficiency program off the ground is a major step forward. The new standards parallel the longstanding light-duty fuel economy (CAFE) standards, though for the larger trucks the standards are put in terms not of miles per gallon but of gallons per ton-mile, reflecting the work done by these trucks.
So what’s next? While the new rule reduces tractor-trailer fuel consumption between 7 and 20 percent, the National Academy of Sciences showed in its 2010 study how tractor-trailer fuel efficiency could be improved by 35 percent in the near-term. The agencies should bring trailers under the rule, which could reduce the fuel consumption of tractor-trailers by another 10 percent. Then they need to begin working on the next phase of the program, which begins in 2019. The huge challenge – and promise – of this next phase is to design a program that treats heavy vehicles as integrated systems, rather than taking a component-by-component approach.
To pull that off, a better picture of how these vehicles are used will be essential. Data on heavy-duty trucks – their specifications, fuel consumption, and duty-cycles – is sparse, especially since the demise of the Commerce Department’s Vehicle Inventory and Use Survey in 2006. That needs to be addressed as soon as possible, along with the further development of vehicle simulation tools that can reduce the number of individual truck models that will otherwise need to undergo physical testing under the program.
Most challenging of all will be to fashion a rule that can drive efficiency improvements tailored to real-world operation without becoming too complicated. The U.S. program is the second to be adopted, after Japan’s in 2005, and truck regulators around the world are watching with interest. An effective program will bring benefits globally, both in terms of fuel consumption and emissions reduction, and in terms of strengthening the market for truck efficiency technologies, an area in which the U.S. is a world leader.