Well-managed fleets focus on fuel efficiency the way a surgeon focuses on the tip of his scalpel. It is, after all, a life-and-death issue
: Small gains in miles per gallon or fractional reductions in cost per gallon can make the difference between profit and loss, and are typically gained only through painstaking effort.

So far the challenge has been a private management issue, albeit much discussed among fleets looking for better ways of doing business. But over the course of the next several years it is going to take on a new dimension, as the government works its way toward setting fuel economy standards for medium- and heavy-duty trucks.

The path to fuel economy regs

There are two parallel efforts under way. One is a research program by the National Academy of Sciences. The other is a rulemaking scheduled to begin next year by the National Highway Traffic Safety Administration.

The cap-and-trade bill passed by the House late in June adds another wrinkle. It would give the Environmental Protection Agency the authority to set greenhouse gas emission standards for new heavy-duty trucks and engines, starting by the end of next year. Should this measure pass, it would in effect take fuel economy regulation away from NHTSA and give it to EPA, says Glenn Kedzie, vice president and environmental counsel for the American Trucking Associations.

"Greenhouse gas regulation and fuel efficiency regulation are heading down two roads but will end up at the same point," he says.

Both the National Academy of Sciences study and the NHTSA rulemaking were ordered up by Congress in the 2007 Energy Independence and Security Act. The original suggestion in an early draft of the bill was to simply require a 4 percent annual fuel economy improvement starting in 2016. Effective industry lobbying set that idea aside in favor of a more considered approach based on an accurate understanding of how the trucking industry actually uses fuel.

The National Academy of Sciences study is attempting to do that.

"We recognize the complexity of this issue," said Andrew Brown, executive director and chief technologist of Delphi Corp. and chairman of the National Academy of Sciences' fuel economy committee.

Brown, speaking at a recent conference on truck efficiency sponsored by the University of Michigan Transportation Research Institute, explained that the committee has until next March to complete its assignment. The committee's findings and recommendations will be passed on to NHTSA for its rulemaking, but meanwhile the agency must undertake its own study as well. The NHTSA study is due next September, and the agency has until 2012 to complete a rule that will take effect in 2016 - depending, of course, on what Congress does in the cap-and-trade bill.

The committee has 19 members, some from academia, some from public interest organizations and several from industry, including Duke Drinkard, vice president of maintenance (retired) at Southeastern Freight Lines, David Merrion, executive vice president (retired) at Detroit Diesel, and Charles Salter, executive director of engine development (retired) at Mack Trucks/Volvo Powertrain.

How to measure economy

The committee is trying to figure out an appropriate way to measure fuel economy for trucks - not an easy assignment, Brown said. "It's very complex. It's not an integrated industry like you see on the light-duty side," he said. "Given the diversity of vehicles and applications, consideration of classification of vehicles will likely be required."

Brown said that miles per gallon may not be the appropriate measure for fuel use in all trucks. "You may have a long-haul truck where something like an mpg standard makes sense, but you may have a work truck where it doesn't make sense. It may still not make sense for a long-haul vehicle, but we need to understand all the complexities, which means understanding the range of duty cycles, the range of actual in-experience use, and the technologies such as aerodynamics and hybrids."

In addition, the committee is charged with assessing the technologies that can be used to improve fuel economy, as well as their costs and the practicality of integrating them into truck manufacturing.

Brown listed a daunting set of issues, beginning with the key question of who should be regulated - the engine or truck manufacturer, the body builder, the owner or user, or all of them.

The committee is looking at whether regulations should cover specific vehicles, or be based on corporate average fuel consumption. It also is studying ancillary fuel economy techniques, such as lifting truck size and weight restrictions and reducing traffic congestion. And it wants to understand the impact of fuel economy regulations on safety, cargo capacity, fleet turnover, equipment resale values and equipment performance.

Where we go from here

The full scope of fuel efficiency technologies is on the Academy committee's list: aerodynamics for tractors and trailers; tires and wheels; weight reduction; the transmission; accessory electrification; idle reduction and management; engine efficiency; waste heat recapture; and hybrids.

NHTSA will use the committee's findings, but at the same time is gearing up its own research effort, as required by the 2007 law, said Mary Versailles, senior policy advisor at the agency.

She indicated that the agency will focus on a set of issues similar to those being studied by the National Academy of Sciences' committee. It wants to know, for example, the baseline fuel efficiency of each category of commercial vehicle, and whether those categories might frame a regulatory approach.

Other questions: What is the right metric for fuel efficiency; which test cycle and type of test should be used to measure efficiency; whether efficiency requirements should be applied to vehicles or to components; and who, from engine builder to truck driver, should be responsible under the regulation.

From the August 2009 issue of Heavy Duty Trucking.