The manufacturers of 2010 EPA emission-compliant heavy duty on-highway diesel engines say their engines have been well received in the marketplace. Reports and feedback coming in from fleet customers, as well as from demo trucks in the field, have been positive, with the engines meeting expectations and consistently delivering fuel economy improvements over the previous generation of engine technology.
To comply with the EPA 2010 diesel emissions standards, the world’s most stringent, commercial truck and engine manufacturers settled on two types of emissions control technologies: selective catalytic reduction (SCR) and exhaust gas recirculation (EGR). SCR allows the engine to be optimized for fuel efficiency and treats the engine exhaust downstream. EGR, also referred to as in-cylinder EGR and enhanced, advanced or massive EGR, reduces emissions in the engine cylinder.
The standards mandate emissions no greater than 0.2 g/bhp-hr (grams per brake horsepower-hour) for nitrogen oxide (NOx) and 0.01 g/bhp-hr for particulate matter (PM). Both EGR and SCR technologies reduce NOx emissions. To decrease PM emissions, both systems employ diesel particulate filter (DPF) technology.
Navistar International, with its MaxxForce engines for its International brand trucks, is the only heavy duty truck company to offer an EGR solution for 2010 diesels. All others, including Daimler Trucks North America, Mack Trucks, Paccar and Volvo Trucks North America (VTNA), along with engine maker Cummins, have gone with SCR technology.
The number of 2010 EPA engines in the marketplace is relatively small due to two significant marketplace influences. One is the slowed economy in combination with the pre-buy last year where fleets got all the trucks they felt they needed, after which truck orders went dry. The other was the substantial upcharge for the engines, required to offset the costs of meeting the new emissions requirements. This had truck users seeking out good used late model equipment and new old stock on dealer lots.
“There’s no doubt that acquisition of 2010 trucks is off to a slow start,” says Allen Schaeffer, executive director of the Diesel Technology Forum. “I’d attribute nearly all of the delayed acquisition to the recessionary economy and not to any issues with the new generation of clean diesel truck engines.
Founded in 2000 and dedicated to raising awareness about the economic importance of diesel engines, the Diesel Technology Forum represents the nation’s engine and equipment manufacturers, fuel refiners and emissions control technology manufacturers. It also serves as a primary resource and partner for policymakers, media and non-governmental organizations on issues and activities related to the use of diesel technology.
Ed Saxman, drivetrain product manager for VTNA, says “there is a growing interest in fleets wanting to buy new trucks.” Tim Shick, director of engine sales for Navistar International, agrees that new heavy duty truck sales are starting to pick up but “builds are being pushed out to the later part of the year.”
Orders for new trucks EPA-compliant diesels are starting to rise, Schaeffer says, and notes Penske Truck Leasing’s ordering 750 Freightliner Trucks and Knight Transportation’s purchase of 370 Volvo VN tractors. At the time of this writing, Daimler Trucks North America had received orders for more than 10,000 trucks, chassis and buses from more than 700 customers. Cummins had built and shipped more than 5,500 EPA 2010 engines, including ISX15, ISL9, ISC8.3 and ISB6.7 models.
“We’ve been very deliberate in rolling out a slow launch for our 2010 EPA engines, which began in September 2009,” says VTNA’s Saxman. “There are hundreds of production trucks with EPA 2010 technology in daily operation with customers and they’re reporting fuel savings, improved performance and excellent reliability. Our D11, D13 and D16 engines are getting fuel economy which is a 5 percent increase over our 2007 engines, and those showed an improvement over previous engines.”
“Our 2010 engines have worked like they were expected too, even in the winter. On some of our test trucks, this past winter was their third winter and there have been no issues.”
“We are in the early stages of commercial release to customers,” David McKenna, director of powertrain sales and marketing for Mack Trucks says. “EPA 2010 Start of Production (SOP) was December 2009. However, the early data indicates improved fuel economy over the exact same spec in a pre-2010 configuration. We are continually seeing the 5 percent improvement as promised, even taking into account weather conditions in the first quarter of 2010, which were not conducive to good fuel economy.”
“After four months into this milestone launch year, we are seeing good response to our Detroit Diesel BlueTec SCR emissions technology,” says Mark Lampert, senior vice president of sales and marketing for Daimler Trucks North America (DTNA). (Detroit Diesel Corporation is an affiliate of DTNA.) Reports coming from current fleet customers and customer demo units equipped with Detroit Diesel’s DD13, DD15 and DD16 engines with BlueTec SCR “are meeting our expectations and consistently delivering up to a 5 percent fuel economy improvement over our 2007 engines.That is a payback of 2 to 4 cents per mile per truck, and it is providing both a payback on the equipment and a hedge against rising fuel prices.”
Some of DTNA’s customers are reporting even better fuel mileage gains. By way of example, Penske Truck Leasing has seen up to a 7 percent fuel efficiency gain over 2007 units; Tri-Hi Transportation, an 8 percent fuel economy jump over other fleet equipment; C.R. England, 8.2 to 8.3 mpg; and Meijer, 12 percent fuel economy over trucks replaced.
Shick says Navistar is seeing the kinds of fuel economy and performance it expected “but there’s really not enough units in the field with enough mileage on them” to make a solid determination yet. “However, we’re not disappointed with what we’ve seen so far.” Navistar has said its 2010 MaxxForce engines “deliver outstanding fuel economy, excellent power characteristics and exceptionally smooth and quiet ride, and high strength without added weight.”
Designed to meet the EPA 2010 emissions regulations, Paccar’s new 2010 MX engines have yet to hit the marketplace. Introduced in February, they will be installed in heavy duty North American Kenworth and Peterbilt trucks beginning this summer, says Alan Treasure, Paccar’s director of marketing. However, orders are already coming in.
The Cummins heavy duty ISX15 is delivering 5 to 6 percent better fuel economy than its predecessor, the EPA 2007 ISX, says Christy Nycz with Cummins’ on-highway market communications department. “Some customers are reporting even better improvements.”
She says driver training techniques and following manufacturer gearing recommendations will also help truck users maximize fuel efficiency of the new 2010 engines, as well as older engines.
Additionally, vehicle insights based on engine diagnostic codes from sensors and components that can packaged and analyzed for tracking performance, as well as faster remedial action, will help with fuel economy, Lampert of DTNA says. Implementation of remote diagnostic programs driven by the advent of technology enhancements will help truck users maximize uptime and optimize revenue generation through remote and immediate vehicle insights on performance and improvements to the long-term reliability and durability of the equipment.” (This type of system will soon be standard equipment on all 2010 Freightliner and Western Star trucks with Detroit Diesel engines equipped with BlueTec emissions systems.)
All of the manufacturer says their emission systems are performing well in the field. “Most of the issues, if any, are specific to fleet tuning and use,” says Lampert, and these are easily addressed. Adds Mack Trucks’ McKenna: “Some production vehicles already have more than 75,000 chassis miles and there have been no complaints regarding the ClearTech system (what Mack trucks calls its SCR emissions technology). On the earlier customer field test trucks, there were the usual bugs that had to be corrected prior to SOP, but there were no major issues.”
Also helping avoid problems was the leveraging by the manufacturers of their extensive European experience with SCR and EGR emissions technology.
There are no significant changes to maintenance with the 2010 EPA engines, notes Cummins’ Nycz, with primary engine maintenance intervals remaining unchanged. With the exception of changing the diesel exhaust fluid filter, there are no additional changes to maintenance practices or procedures, adds DTNA’s Lampert.
“To see these new engines come out with near zero emissions and be as clean as alternative fuels is nothing short of a major milestone,” says Diesel Technology Forum’s Schaeffer. “The level of research and innovation that the engine and truck makers have done to get here is extraordinary. This accomplishment positions clean diesel as a technology for the future.”
He points out that clean diesel technology involves three pieces. One is low sulfur diesel fuel - is a cleaner-burning diesel fuel that contains 97 percent less sulfur than low-sulfur diesel and allows the use of improved pollution control devices that reduce diesel emissions more effectively. The other two pieces are low-emitting diesel engines and advanced emissions control devices. There is also the element of being able to leverage programmable electronic features, says Nycz of Cummins.
The “most extraordinary fact” is that heavy duty on-highway diesel engines manufacturers have been making dramatic strides in recent years in reducing emissions and at the same time increasing fuel efficiency - basically competing forces in diesel engine design, says McKenna of Mack Trucks. “These have long been competing goals from both a technical and customer group, adds Schaeffer of the Diesel Technology Forum. “It is remarkable that given the 99 percent reduction in PM and NOx emissions that we have not seen a substantial reduction in fuel economy.”
“Clean Diesel is not a contradiction in terms,” McKenna observes. “The amount of soot is completely invisible to the naked eye. The amount of NOx emitted is essentially zero, or as near to zero as 0.2 grams can be. 0.2 grams equals 0.000441 of a pound. Not much at all.
“Couple the near zero exhaust emissions with a goodly 5 percent improved fuel economy and we are ‘green’ in two ways - we’re environmentally friendly, and we put green dollars back into the customers’ pocketbook with the lower fuel consumption savings.”
“2010 diesel engines are at a level now where in the cities with poor air quality, the ambient air going into the engines is dirtier than the emissions coming out,” Navistar’s Shick says. “You’ve got to wonder how much cleaner diesels can be.” He feels the next focus will be on carbon dioxide (CO2) “because no matter how clean you burn diesel fuel, some CO2 will be formed.”
The EPA does not classify carbon dioxide by itself a pollutant, but considers it a hazard to human health as a greenhouse gas which contributes to global warming, says VTNA’s Saxman agrees. He, too, believes “CO2 will probably be the next focus of regulations, but we’re not at a point yet where this has even been defined.”
“In terms of new emissions regulations, we believe it’s not a matter of if, but rather what and when,” says Cummins’ Nycz. “It is reasonable to assume that in the future, there may be a regulation on greenhouse gases, however any details are unknown at this point.”
It would be near impossible to get today’s heavy duty diesel engines any cleaner, adds McKenna of Mack Trucks. “The next target, I’m sure, will be CO2. This will likely entail various technologies to reduce CO2 production, including but not limited to, more restrictive idle controls, shore power for parked sleeper units, electric APUs, low-rolling resistance tires, all types of truck, tractor and trailer aero aids and the like. The current EPA SmartWay-type vehicle provides a basic model for the future.”
“The future is going to be all about reducing emissions of CO2 - shorthand for increasing fuel economy,” Diesel Technology Forum’s Schaeffer says. “One big shift is that instead of just focusing on making the engine more efficient, any future effort is likely to focus on the total vehicle. The truck, its tires and its aerodynamic profile all have significant impacts on fuel economy.”
He points to a substantial research effort on approaches for improving fuel economy in medium and heavy duty vehicles just completed by the National Academy of Sciences. The research, presented to the National Highway Traffic Safety Administration, forecasted about 20 percent more improvement in energy efficiency out of the engine alone. It said the use of hybrid powertrains in medium duty pickup and delivery type vehicles will grow, and efforts to improve aerodynamics in trucks and trailers will take on new significance, as will tires and how the driver drives - a key variable in reducing fuel consumption from heavy duty trucks.
The engine is a piece of the equation and so is aerodynamics, says Navistar’s Shick. “In our testing and research, we’ve found that in round numbers, about 50 percent of the fuel consumed by a highway tractor at 60+ mph is used to overcome aerodynamic drag. Another 15 to 16 percent is the engine itself and the balance is the load - tires against the pavement, geartrain, etc. So a relatively small portion of fuel use is due to the engine.”
For post 2010, efforts will be focusing on an integrated vehicle for more fuel economy and reduced emissions, he says and “we’ll see very different looking configurations aerodynamically for both tractors and trailers, particularly trailers as not much has been done with them.”
DTNA’s Lampert notes that the U.S. Department of Energy’s SuperTruck Program has awarded grants to the truck manufacturing industry to develop the next generation of fuel efficient heavy duty trucks. Project goals include the demonstration of a 50 percent total increase in vehicle freight efficiency through a five-year research and development process focusing on advanced vehicle systems and engine technologies.
DTNA is a recipient of some of the program’s $187 million grant money. So are Cummins, Navistar and Peterbilt.
“It’s hard to imagine cranking down any further on heavy duty diesel emissions standards like NOx and PM, given that they are so close to zero,” says Schaeffer of the Diesel Technology Forum. “I think the emphasis for new vehicles is going to be holding the line on emissions, but seeing targets for reductions in CO2 and gains in fuel efficiency.
“However, I think that if there is any additional regulatory activity on the emissions aspects of diesel, it is more likely to come in the form of addressing emissions of the in-use fleet of vehicles with a focus on fleet operations, more so than new engine technology/standards and manufacturers. The Diesel Emissions Reduction Act established a voluntary incentive-based program aimed at on- and off-road fleets to modernize and upgrade their older technology through a variety of approaches, including repowers - putting in newer engines, adding emission control devices like particulate filters or oxidation catalysts, etc.”
The next regulations come in 2013 when all on-highway diesel engines will require on-board diagnostics (OBD) systems, says Nycz of Cummins.
Manufacturers must install OBD systems that monitor the function of emission control components and alert the vehicle operator to any detected malfunction or deterioration with the emissions system prior to emissions exceeding a threshold. When a malfunction occurs, diagnostic information must be stored in the engine’s computer to assist in diagnosis and repair of the malfunction.