Cover Story: The road to greener trucks
February 06, 2013
by Sean Kilcarr
Vehicles changing to meet GHG/fuel efficiency regs
Greenhouse gas and fuel efficiency have become as much a part of the lexicon of trucking as freight and rates. Yet, the impact these few simple words are having on the industry is indisputable. In 2011, the Environmental Protection Agency (EPA) in conjunction with the National Highway Traffic Safety Administration (NHTSA) issued new regulations regarding heavy-duty vehicle fuel efficiency and greenhouse gas limits.
To be phased in from 2014 through 2018, the regulations, at least the initial requirements, are being met with relative ease among manufacturers and suppliers. But with each successive year, the requirements get a little bit tougher, and that has truck manufacturers looking at any number of possibilities to help meet the standards. And while the regulations do not specify changes to aerodynamics, transmissions or oils, truck OEMs are leaving no stone unturned as they try to produce the ultimate fuel-efficient vehicle.
What are the standards?
EPA predicts the greenhouse gas/fuel economy rules will save the industry some $50 billion in fuel costs with diesel priced at $3.50/gal. Even with an $8 billion price tag to meet the requirements, EPA says the trucking industry should see a net gain of $42 billion.
Under the GHG14 regulations, trucks and buses built in 2014 through 2018 are projected to reduce oil consumption by 530 million barrels and greenhouse gas emissions by 270 million metric tons.
But what are the rules, exactly? According to Byron Bunker, acting director for the compliance division of the EPA’s Office of Transportation and Air Quality, the rules actually mandate separate yet parallel efficiency improvements for engines and vehicles. EPA expects engine fuel efficiency to improve 3% in 2014 and a further 3% by 2017.
The rules are based on the size and weight of the vehicle, meaning there are many different iterations of the regulations. In fact, the type of vehicle matters as well; within the Class 7 and 8 combination tractor category, the differences in expected emissions and fuel consumption change with the key attributes associated with the vehicles, such as GVWR, cab type, and roof height.
Here are the basics:
*Most, but not all, tractor-trailers will be required to achieve up to about a 20% reduction in fuel consumption and GHG emissions by model year 2018, saving up to 4 gals. of fuel for every 100 mi. traveled.
*For heavy-duty pickup trucks and vans, separate standards are required for gasoline- and diesel-powered trucks. These vehicles will be required to achieve up to about a 15% reduction in fuel consumption and GHG emissions by model year 2018. Under the finalized standards, a typical gasoline- or diesel-powered heavy-duty pickup truck or van could save 1 gal. of fuel for every 100 mi. of travel.
*Vocational vehicles, including delivery trucks, buses, and garbage trucks, will be required to reduce fuel consumption and greenhouse gas emissions by about 10% by model year 2018. These trucks could save an average of 1 gal. of fuel for every 100 mi. of travel.
Tractor-trailers and vocational vehicles must meet targets for gallons of fuel consumed and GHG emissions per ton-mile. This figure is calculated by dividing gallons of fuel consumed and grams of carbon dioxide emissions per mile by tons of freight hauled.
Where to begin?
On the vehicle side, fuel economy gains are expected to be derived from five main areas, says Bunker. These are aerodynamic improvements, reductions in tire rolling resistance, vehicle weight reductions, speed limiting technology, and reductions in engine idling. He stresses, however, that fleets will not be compelled to make any specific changes to engine, transmission, or axle specs.
“We want fleets to maintain the ability to make spec’ing decisions based on their actual operations, not a national average standard,” he adds. “They need to be able to optimize their vehicles correctly.”
Even with that flexibility, though, truck makers have their work cut out for them.
Al Pearson, director of the vehicle test group for Daimler Trucks North America (DTNA), notes that there are more than 50 low rolling resistance tire models available for steer axles, with another 50 available for drive axles.
Pearson points out that the aerodynamic category alone is made up of five distinct “bins,” while Class 7 and 8 trucks will be broken down into nine separate categories for GHG/fuel efficiency designation.
On top of that, the new rules task OEMs with determining the classification for each vehicle they build, be it a long-haul tractor-trailer, medium-duty truck, or vocational vehicle. While vocational trucks will have the most leeway in complying with the new rules, OEMs will be restricted to building 21,000 such units in a three-year period.
Truck engine manufacturers must certify their products as well, but that certification is separate from the vehicles.
One tool, many calculations
The “certification process” revolves around OEMs being tasked to calculate and then certify the GHG emissions levels for each class of vehicle they build using a special greenhouse gas emissions model (GEM) tool developed by EPA to ensure manufacturers are building trucks on a yearly basis that emit no more than the GHG grams per ton-mile levels set for each vehicle classification.
GEM is a free desktop computer application designed to use algorithms to gauge the GHG emissions (and thus fuel efficiency) produced by a slew of truck components, from tires and transmissions to engines.
“Specs will need to be extracted exactly as ordered and plugged into the GEM tool, so we’re going to need an automated documentation system to do it,” says DTNA’s Pearson. “It shows how complex calculating all of this is going to be.”
Initially, items such as low-rolling resistance tires and aerodynamic fairings will go a long way to meeting the regulations. As the regulations stiffen over the years, though, more work will need to be done. That’s why manufacturers are looking at every aspect of the vehicle to see where efficiencies can be achieved.
Engines, too, must meet greenhouse gas standards. Detroit has achieved early certification of its entire 2014 engine lineup.
“It is our goal to pace the industry in emissions compliance and fuel efficiency. Early submissions for GHG14 engine compliance is evidence of this strategy for the updated family of Detroit engines,” says Brad Williamson, manager of engine and component marketing for DTNA. “The Detroit brand is synonymous with power and efficiency, and our enhanced engine lineup builds on our tradition of providing our customers with the best performing products in the market today while meeting the emissions regulations.”
Cummins has also achieved early certification of its ISX15 and ISX12 powerplants.
“Cummins 2013 truck engines will deliver better fuel economy with no major hardware changes,” says Jeff Jones, Cummins vice president of sales and market communications. “The certification of the ISX15 demonstrates Cummins’ commitment to deliver products that exceed both environmental and customer requirements.”
Jones points out that the ISX15 will achieve up to 2% improved fuel economy over the current product with only minor changes, most related to calibrations.
Transmissions are another area where work is being done to improve fuel efficiency. Again, while not directly specified by NHTSA and EPA, many manufacturers see more efficient transmissions as part of the solution.
Mack Trucks’ mDrive and Volvo Trucks’ I-Shift transmissions are among those on the market that seek to maximize fuel efficiency by keeping rpm in the engine’s “sweet spot” as much as possible. Eaton’s UltraShift and UltraShift Plus and Allison Transmission’s new TC10 TS are other options that operate with the same goal in mind.
Detroit is launching the DT12 this year, a transmission designed as part of an overall powertrain package aimed at improving fuel economy. The DT12 smoothes out torque inputs to protect the driveline and gives the driver a choice between economy and performance driving characteristics.
Allison, Dana Holding Corp. and Fallbrook Technologies are working to bring a continuously variable transmission (CVT) to the trucking market before the end of this decade, a transmission designed to boost fuel economy and vehicle efficiency while significantly reducing weight. The companies will use Fallbrook’s NuVinci CVT design.
“We’re exploring exclusively producing transmission components under this agreement,” says Roger Wood, Dana president & CEO. “We expect it will take two to three years to optimize the technology and then ramp up to full-scale manufacturing.”
William Klehm III, chairman & CEO of Fallbrook, says the key to the company’s NuVinci CVT design is the use of what he calls “balls and discs” to replace the gears used in a traditional transmission. Tilting the balls changes their contact diameters and varies the speed ratio, thus providing what Klehm says is “an unlimited number of gear ratios” to optimize engine efficiency, thus improving fuel economy.
“It also means the transmission is less complex, scales and packages more easily, and costs less to manufacture—all while achieving optimum performance,” he notes.
The regulations are having an indirect effect on oil as well, a study notes. Frost & Sullivan’s Sandeep Kar, global director of commercial vehicle research, and Wallace Lau, truck research analyst, say that to boost engine efficiency and thus fuel economy, a switch to much lower viscosity formulations must take place over the next six years.
Research by both Kar and Lau indicates that 5W-40 and 5W-30, even so-called “zero weight” oil blends of 0W-20 and 0W-30, are being developed for medium- and heavy-duty truck engines in an attempt to generate the fuel savings necessary to meet federal fuel economy rules. However, Lau stresses that the challenge for such “low” and “no weight” oils will be to maintain engine protection properties as well as temperature handling characteristics.
Battling the heat
“Right now, one of the issues with low viscosity oils is that they do not apply well in warmer regions of North America,” Lau points out. “Yet [diesel] fuel costs across all of the U.S. and Canada are predicted to only keep rising, so fleets want the fuel-saving advantage of a low viscosity fluid. Our fleet-focused research indicates steadily rising interest in advanced engine oils, which is already translating to rising aftermarket demand for synthetics and semi-synthetics.”
The desire for oil that helps improve fuel economy is evidenced by the process already underway to develop a new oil category. This was started by the American Petroleum Institute (API), the governing body that oversees oil and other petroleum classifications, along with truck makers and engine manufacturers. Currently called Proposed Category 11 (PC-11), this new category will likely include two different oils for fleets: a fuel-efficient, low-viscosity version to meet the demands of 2014 and newer engines, and one that is backwards-compatible for older powerplants.
Slated to debut in January 2016, the lower viscosity oil that will be required to help new engines meet federal fuel economy standards may not be suitable for older engines, according to Dan Arcy, global OEM technical manager for Shell Lubricants.
BAD MIX FOR CARRIERS
One drawback to this development is that companies with a mix of older and newer equipment may be saddled with using different oils.
In addition to the new viscosity characteristics, PC-11 will include a number of updated or new specifications and tests required by recent changes in engine technology and materials. Arcy says the new tests should result in improvements in oxidation and shear stability, aeration reduction, scuffing and adhesion wear, and biodiesel compatibility.
With all the moving parts that continue to be shuffled around to meet ever-changing regulations, the result can sometimes be growing confusion among truck buyers. Along with all the changes happening to meet the greenhouse gas/fuel efficiency regulations, trucks and tractors will continue to see advances in aerodynamics and weight reductions, to name just two.
As part of that, engines will see additional changes in terms of size and power density, according to a survey by Frost & Sullivan. The firm projects that the average displacement for Class 8 truck engines in the U.S. is going to shrink anywhere from 2% to 3% by 2018 as OEMs and fleets alike seek ways to improve fuel economy and payload capacity simultaneously for tractor-trailers.
However, Kar says the power density of Class 8 engines will actually increase significantly—some 6% to 8%—over the next six years even as they shrink in size, providing in many cases an opportunity, in his words, for fleets “to have their cake and eat it too.”
“What we’re finding is that criteria such as total cost of operation [TCO] are becoming more important to fleets in the face of rising fuel prices,” Kar says. “The upfront purchase price and total lifecycle costs of smaller engines are lower, while fuel economy is better.”
The key is that power isn’t necessarily lost in the transition to smaller engines anymore, he explains, meaning fleets don’t necessarily have to sacrifice performance to gain a better TCO position. And it’s the ability to retain power density that’s getting more fleets to consider “downsizing” their truck engines, Kar says.
RISING PRICES, RISING PROFITS
Based on its research, Frost & Sullivan projects that average Class 8 truck engine displacement will fall to between 13.4L and 13.7L by 2018, down from an average range of 13.7L to 14.1L back in 2011. Conversely, average horsepower will climb to between 425 and 540 by 2018, compared to a range of 400 to 520 back in 2011. Torque will also jump as well, increasing to between 1,300 and 1,750 lbs.-ft. on average compared to between 1,250 and 1,650 lbs.-ft. averaged in 2011.
The end result? While truck buyers can expect to see an increase in sticker prices due to the technological improvements to meet new regulations, the overall drop in fuel costs is predicted to offset that, leaving truckers to run rigs that are more efficient, cleaner and profitable.