Pipe Dreams

Emile Hoffman is a worried man.

As director of field service support for Houston-based Waste Management Inc., Hoffman oversees the purchase and integration of new trucks into the company's fleet of some 50,000 vehicles. What has him concerned, however, are the new cleaner diesel engines he'll have to buy for his approximately 30,000 heavy-duty Class 8 trucks after October 1 of this year.

By then, the Washington-D.C.-based Environmental Protection Agency (EPA), is requiring all new heavy-duty diesel engines to emit no more than 0.10 grams per brake horsepower hour (g/bhp-hr) of particulate matter (PM), 2.0 g/bhp-hr oxides of nitrogen (NOx), and between 0.4 and 0.5 g/bhp-hr of non-methane hydrocarbons (NMHC). The NOx and NHMC measurements typically are combined for testing at 2.5 g/bhp-hr.

Engine manufacturers have ramped-up to produce less-polluting engines. However, "my biggest fear is that there has been limited field testing of these engines in the waste industry," Hoffman says. "Much of the testing for these new engines has been done with over-the-road fleets, which operate their trucks at consistent highway speeds. We are a stop and go operation, which is very different. So we are concerned about how these engines will perform."

Waste Management currently is field testing four of the new reduced-emissions engines, but testing just began in April -- a short window in which to study them, Hoffman says. For a fleet that purchased 2,400 new trucks in 2001 to replace old equipment, any engine performance issues could affect how Waste Management calculates vehicles costs. And those numbers obviously will affect the bottom line.

"We keep our trucks from 10 to 14 years," Hoffman says. "So if these engines wear out faster or need to be maintained more, that adds to our fleet costs ... No one really knows what will happen with these engines in our industry. The good side is that we'll have cleaner air since these engines produce less pollution. But there could be a flood of problems if the engineers haven't built them right."

Rules and Consequences

The October 2002 rules, however, are just the beginning of far-reaching diesel emission changes the EPA has mandated over the next eight years.

In 2004, the October 2002 rules will be expanded to include medium- and light-duty diesel truck engines.

By 2007, emission level requirements will be reduced another 90 percent. PM emission levels will decrease to 0.01 g/bhp-hr, NOx to 0.2 g/bhp-hr and NMHC to 0.14 g/bhp-hr. The PM requirement will go into full effect in 2007, while the NOx and NMHC requirement will be phased- in between 2007 and 2010.

The net effect of these rules means diesel engines in 2010 will have 1/10th the emissions of 2001 models — cleaner than even natural gas-powered engines of the same size, the EPA says. Furthermore, all on-road diesel engines powering trucks with a gross vehicle weight rating (GVWR) of more than 8,500 pounds must comply with those standards. Financial penalties will be imposed on those that don't.

Reaching the 2007 emission targets will require switching diesel fuel, too. So starting June 1, 2006, low-sulfur diesel will be the only fuel available to diesel-powered trucks. The level of sulfur content in diesel fuel will be reduced from 500 parts per million (ppm) today to 15 ppm in 2006.

Tallying the Costs

What does this mean for waste fleets?

Everyone agrees that the cost of diesel engines and diesel, along with a host of other truck-related operating expenses, could rise.

The EPA estimates that all of the diesel engine changes and aftertreatment devices needed to reach 2007 emission levels may add between $1,200 to $1,900 to the cost of a truck. Industry experts suggest a higher figure of $3,000 extra per vehicle, rising to $10,000 once the 2007 standards go into effect.

The EPA also estimates that low-sulfur diesel will be four to five cents more expensive per gallon compared to current diesel blends. The American Petroleum Institute, Washington, D.C., on the other hand, predicts low-sulfur fuel will cost 15 cents extra per gallon.

None of these predictions, however, account for the 3 percent to 6 percent reduction in fuel economy 2002 field-tested emission-compliant engines have recorded. The estimates also don't include possible increased maintenance costs that the new engines and aftertreatment systems may require. And costs from reduced oil drain and lubricant intervals, primarily because of higher amounts of engine soot and heat being generated by emission-reduction technology, have not been added.

“Manufacturers are not just sticking emission control devices on engines,” says Allen Schaeffer, executive director for the Herndon, Va.-based Diesel Technology Forum (DTF). “This technology is being integrated within the engine and with the exhaust and fuel systems. It's complicated, and it all has to work together seamlessly.”

Emission Concerns

Diesel engine emissions are a concern, particularly NOx, sulfur dioxide (SO2), coarse particulate matter (PM-10, smaller that 10 micrometers in diameter) and fine particulate matter (PM-2.5, smaller than 2.5 micrometers in diameter), according to the DTF.

Some environmental groups believe PM, or “soot,” can cause cancer in humans. Diesel engine exhaust contains between 100 to 200 times more small particulates than gasoline engine exhaust, according to the Calif.-based Natural Resources Defense Council (NRDC). NOx is considered a major contributor to smog and ozone depletion; NOx from on-road diesel engines accounted for 26 percent of the more than 23.3 million tons of NOx pollution produced in the country in 1996, the NRDC states.

The EPA has long planned to cut emissions from on-road diesel engines, and the engine manufacturing industry has been preparing to meet those targets. However, engine makers originally expected they would have until 2004 — not 2002 — to comply.

The issue came to head in 1998, when the U.S. Department of Justice, Washington, D.C., and the EPA threatened to sue diesel engine manufacturers over what it called "defeat devices." According to the EPA, defeat devices, part of the engine's electronic control module (ECM), or "brain," turned pollution controls on within the engine during certification tests, then turned them off once a truck began operating on the highway. But the engine makers say those devices functioned according to EPA rules, turning pollution controls off only during extreme operating conditions, such as driving up steep hills.

In the end, the industry's seven major diesel engine manufacturers -- Caterpillar Engine Co. Cummins Inc., Detroit Diesel, International Truck and Engine Corp., Mack Trucks/Renault VI, and Volvo Inc. -- agreed to a settlement. They paid $83.4 million in civil penalties and pledged to collectively spend more than $850 million to introduce new cleaner engines by 2002, two years ahead of schedule.

This cut the normal research and development phase for new engines in half, forcing engine manufacturers to go to market with technology not tested as thoroughly as they would like. For example, while Cummins Inc., Columbus, Ind., was performing 6 million miles of equivalent road tests on its new engines, much of its testing took place in over-the-road applications, with little conducted in vocational markets.

Technology Battle

Another twist involves the technology that's cutting diesel engine emissions.

Most engine makers are using cooled exhaust gas recirculation (EGR) technology to achieve the 2002 and 2004 emission mandates. With cooled EGR, the exhaust air coming out of the engine's combustion chamber is cooled to 350 degrees and reintroduced into the engine to "burn off" emissions, according to John Wall, chief technical officer for Cummins. Anywhere from 5 percent to 30 percent of the exhaust is recirculated, with exhaust heat dispersed through the radiator instead of the tailpipe, he says.

Caterpillar is forgoing EGR entirely in favor of what it calls advanced combustion emissions reduction technology (ACERT). John Campbell, director of truck engine products for the Peoria, Ill.-based company says ACERT engines will not require the "beefed-up" cooling systems necessary for cooled EGR. Additionally, Campbell says fuel economy will remain relatively the same and the engines will be 50 percent quieter.

ACERT engines, however, won't be ready for production until mid-2003, meaning Caterpillar will be subject to EPA fines, Campbell admits.

Thus, waste fleets may find themselves in a conundrum. All EGR-equipped engines create a sulfur buildup, according to the engine manufacturers. That in itself is not bad. But as EGR cools down exhaust temperature, moisture can form within the engine, which may react with the sulfur in the diesel fuel to form sulfuric acid, Wall explains. Sulfuric acid, in turn, could cause excess engine wear and damage, although at this point in EGR development, it is difficult to say how the real the threat is.

The fallout from these engines for truckers large and small is worrisome, according to Robert Delaney, vice president of St. Louis-based Cass Information Systems, and Rosalyn Wilson, an independent logistics consultant. In the pair's annual "State of Logistics" report, they say the EPA originally estimated that the cost to comply with the new emission standards would total $320 million. Their estimate is near $2 billion.

On to 2007

When 2007 regulations go into effect, the situation will get even more complicated as aftertreatment systems and low-sulfur diesel fuel enter the mix.

Low-sulfur fuel is a vital ingredient, because sulfur can “poison” NOx absorbers, catalysts and particulate traps envisioned for trucks, says Patrick Charbonneau, chief technical officer for International Truck & Engine Corp., Warrenville, Ill. Without low-sulfur fuel, engine makers say 2007 emission levels are impossible to obtain. Additionally, engine manufacturers are using EGR and other technologies mainly to reduce NOx levels — leaving particulates to be eliminated by exhaust “filters,” he says.

These filters use precious metals, such as platinum, to eliminate particulates. Although they are effective, such filters are expensive. Platinum can cost as much as gold by the ounce, meaning this could substantially increase exhaust system prices, says Larry Strawhorn, formerly vice president of engineering for the Alexandria, Va.-based American Trucking Associations, one of the trucking industry's largest lobbying groups.

Aftertreatment also is needed to reduce NOx to its required levels. Allentown, Pa.-based Mack Trucks is experimenting with selective catalytic reduction (SCR) technology to cut NOx emissions from its Class 8 diesel engines. SCR adds a chemical, called urea, to the exhaust stream to separate NOx's oxygen and nitrogen elements. The high heat of the exhaust stream causes urea to react with NOx, creating ammonia gas, which contains nitrogen and hydrogen. The hydrogen then bonds with oxygen within the exhaust catalyst, leaving nitrogen and water coming out the tailpipe, Mack explains.

Using urea to clean diesel exhaust has been used for nearly seven years on diesel generators found in power plants. However, power plants operate at a steady engine load and consistent revolutions per minute (rpm), whereas truck engine speeds vary. This means the amount of urea sprayed into the exhaust must be constantly adjusted, or pure ammonia — an element far more dangerous than NOx — will end up coming out of the tailpipe, Mack says.

Truck makers also need to determine how to fit aftertreatment systems on their vehicles.

“The question really is how much space will be needed,” says Jim Bechtold, chief engineer for Seattle-based Kenworth Truck Co. “If SCR is used, then the system will need a tank to hold urea and an injection system to put the urea into the exhaust stream. Controlling that process is another issue: it may require its own ECM and wiring harness. Or, maybe we can control it using the engine's ECM. That's still to be determined.”

Aftertreatment system location is a big concern, Bechtold adds, noting that most particulate filter designs need a high level of heat for regeneration. This may mean restricting the location of the aftertreatment system to areas of the truck that are closest to the engine where high heat levels are easily maintained, he says.

“Where the exhaust stack and muffler is on a truck today may not be where it will be located in 2007,” Bechtold says. “From an engineering perspective, that changes how we may have to put a truck together. Packaging this system — not so much getting the technology to work — becomes the real challenge for the emission control companies, the engine manufacturers and us.”

Bechtold says that his job is to incorporate the aftertreatment system on the truck without affecting the vehicle's functionality. But who knows how this will affect total truck costs, he says.

Time Will Tell

Engine manufacturers and aftertreatment suppliers are looking to gain real-world knowledge as new emission-compliant engines go into widespread use this October.

The EPA also still is trying to determine how to test trucks on the road to ensure they comply with new emission standards [See “The EPA's View” on page 31]. No one is sure how “mobile testing” technology will work, says Christine Vujovich, vice president of environmental policy and product strategy for Cummins.

“The conflict here is that with emissions control comes added cost,” she says. “There will be front-end and life cycle costs with this new technology. That bottom line consideration is so important because the margins in the trucking industry are so thin. That's what we are up against as our engines evolve to meet these new standards.”

Sean Kilcarr is senior editor for Waste Age's sister publication, Fleet Owner magazine.


The environmental benefits of cleaner diesel engines are worth the costs, says Karl Simon, the deputy director for the Washington, D.C.-based U.S. Environmental Protection Agency's (EPA) Office of Transportation and Air Quality (OTAQ), assessment and standards division.

The potential health benefits from cleaner diesel engines could be huge, he says. “We will be saving $70 billion in health-related costs associated with cleaning up the air,” he says. “Remember, too, that approaching emission reductions at the national level will alleviate the need for local and state emission-cutting efforts. Instead of 50 or 100 different emission level mandates, there will be just one.”

To ensure everyone is playing the on same field, the EPA plans to use “mobile testing” devices to conduct spot inspections of trucks on the road. “In the past, we took the engine out, tested it for a few days, then put it back in the truck,” Simon says. “That's very inefficient. But equipment that we can attach to a truck for a day or two is a much more viable method. Not only will it make sure the new standards are met, it will ensure that there will be no advantages gained from operating older engines.”

The EPA also is trying to develop incentives, such as mobile credit trading, to give fleets a financial benefit to adopting clean diesel technology. “Everything is on the table right now,” Simon says. “At the local level, for instance, fleets in non-attainment areas might get tax credits for using cleaner fuel and retrofitting their engines.”


Some over-the-road trucking fleets may be turning to the used truck market to avoid buying vehicles equipped with new and more expensive low-emission diesel engines that go into effect on October 1. Yet for waste management fleets, that option might not be viable.

“There is a lack of used equipment in [the waste] market, despite the overall glut of used trucks today,” says Geoff Stigler, vocational marketing manager for International Truck & Engine Corp., Warrenville, Ill. “Over-the-road fleets can decide to keep their trucks longer or purchase used equipment because they typically keep their vehicles just three years. Consequently, there's a lot of low mileage, late model equipment available.

By contrast, most waste collection fleets keep their trucks anywhere from eight to 12 years — literally until they are dead. “That doesn't leave a big pool of durable used equipment for waste fleets to choose from,” Stigler says.

Typically, the used truck inventory for Class 8 tractors hovers at 170,000 units a year, according to the Indianpolis-based Used Truck Association. But in 2001, the number of used Class 8 trucks ballooned to 200,000 units, largely as a result of decreased trade-in cycles. This created a major market glut, and the industry predicts there will be between 240,000 to 310,000 used Class 8 vehicles available in 2002, a 20 percent to 65 percent jump in just one year.

Much of the inventory is comprised of Class 8 sleeper tractors, the UTA says. In fact, Daycab demand has risen so much that one major truck manufacturer is remanufacturing used Class 8 sleeper tractors into daycabs.

Waste trucks, on the other hand, are more complex pieces of equipment. “We have a ‘tail’ behind our trucks that is different from the trailers used by over-the road fleets,” explains Emile Hoffman, director of field services support for Waste Management Inc., Houston. “If we change our planned purchase flow, that affects the manufacturing capabilities of our body suppliers. Slowing down our new truck purchases creates a bad domino effect in our vehicle supply chain.”

For that reason, as well as because older equipment is more expensive to maintain, it may be cheaper in the long-run to buy waste trucks equipped with the new low-emission diesel engines, Stigler says.

“Waste fleets spend on average $25,000 a year on parts and service for one truck, largely on suspension, brake and body service requirements,” he says. The older such trucks get, the more the fleet has to spend. So, managing the extra needs of low-emission diesels may cost less over the long haul.

“The reduced fuel economy and more frequent oil changes required by these new engines will have less of an effect in the stop-and-go operating environment of waste fleets,” Stigler says. “That's why we think, once we get past October 1, things won't be as bad as everyone thinks.”