Engine Trouble

Consider it a parting shot from the Clinton administration. On Dec. 19, the U.S. Environmental Protection Agency posted a rule requiring dramatically cleaner diesel fuel and exhaust, starting in 2006. The result will be the cleanest diesel engines ever-“It is hard to imagine you could get much cleaner,” EPA Administrator Carol M. Browner said at the time-and the highest engineering hurdle yet for fuel refiners and engine companies.

For fuel refiners, practically all sulphur will have to be removed from diesel fuel-from 500 parts per million down to 15 ppm-starting in 2006. In a concession to concerns about refiners’ ability to supply the fuel, EPA is phasing the requirement: 80% of diesel fuel will have to meet the standard by 2006; the remaining 20%, primarily diesel used off-highway, has until 2010.

Engine manufacturers will have to take 90% of particulate matter out of their exhaust by 2007, and cut nitrogen oxide emissions in two stages, starting in 2007 and finishing in 2010.

The new rules will affect Canadian truck buyers the same as every other emissions edict coming out of the United States. Transport Canada and Environment Canada are expected to mirror the EPA rules in regulations of their own.

Jed Mandel of the Engine Manufacturers Association, a lobby group for diesel engine makers, thinks the EPA is taking the right approach in combining engine and fuel requirements in a single rule. At the same time, he warned, “Our ability to achieve these unprecedented emission reductions is by no means a certainty,” Mandel said.

One reason: with exhaust gas recirculation devices on engines a certainty by 2006, they now must count on refiners to ensure widespread availability of ultra-low-sulphur fuel.

The 2007 announcement comes at a time when engine makers and truck manufacturers are struggling to meet a larger-looming deadline: October 2002. This is when Caterpillar, Cummins, Detroit Diesel, International Truck & Engine, Mack Trucks, Renault V.I., and Volvo Truck Corp. agreed to meet emissions targets initially scheduled for January 2004 in a consent decree stemming from accusations that they programmed their engines to cheat EPA emissions tests.

The engine manufacturers, for their part, say they can make October 2002 with compliant engines. The trouble is, they’re having difficulty meeting the production deadlines of truck makers.

Meeting the accelerated EPA schedule has required engines to be dramatically redesigned. The technology favored to meet the new limits is exhaust-gas recirculation (EGR), where a certain amount of recirculated and cooled exhaust is introduced into the combustion mixture, replacing some of the air in the cylinders. Since the air is 20% oxygen, this reduces the amount available to the combustion process, resulting in a combustion with lower peak temperatures and less nitrogens in the exhaust, but with cylinders still filled with a useful working mixture.

Truck engineers are having to refine their truck designs-specifically the underhood area-to accommodate EGR (at the very least, a larger cooling system is needed to handle the heat rejection these engines will generate). Furthermore, each engine manufacturer is coming at EGR from a slightly different perspective-truck engineers cannot count on standard positioning of EGR components, for example.

As yet, no truck research and development centre has seen a finalized version of the October 2002 engines. Peterbilt chief engineer Craig Brewster says the engines he has seen involve major new interfaces with the chassis in terms of cooling systems, aftercoolers, and the general underhood environment. He says it’s impossible to do much development work until the engines have progressed to production-ready configurations.

Freightliner president Jim Hebe, an outspoken critic of the October 2002 deadline, says the time is past for his company to commission any major tooling-modifications to a truck hood, for instance. He says the only possible outcome is that, under the current timetable, truck manufacturers will have to seriously limit customer choices for engine/chassis combinations. And that’s not good news if you’re going to be in the market for a truck in fall 2002.

IS ANYONE LISTENING

Complicating matters, the EPA failed to meet some deadlines of its own. The agency had committed to requiring all diesel engine manufacturers-not just the seven that signed the consent decree-to abide by tough new emissions testing procedures by 2004. But the EPA failed to hit its date for getting the rules rewritten and promulgated. Consequently, the seven “cheaters” will have to run by a set of more stringent rules than their competitors until the January 2007 restrictions take effect. This has spawned a flurry of proposals:

– Interim rules. Caterpillar and Cummins petitioned the EPA to create a new rule for 2005 that would apply to all engine makers, or to postpone some of the more onerous requirements of the October 2002 deadline to October 2003. They fear jobs will be lost if they have to meet stiffer emissions requirements than Japanese or European engine manufacturers have to meet in 2002.

– Separate standards. Another alternative open to the consent-signing companies is to create two separate engine ranges, one that would comply with the rules from October 2002 until 2004, then another to meet the existing 2004 through 2007 rules.

– Regulatory end-around. Fourteen states, led by California, hope to make up for the EPA’s ineffectiveness by banding together and writing their own emissions rules, effectively putting in place what the EPA was too tardy to accomplish. California is the only state in the nation that, under the U.S. Clean Air Act, can write more stringent requirements than the EPA.

And once California has it on the books, other states can follow, prohibiting sales of trucks that don’t meet their standards. Since about 40% of all diesel sales are in the 14 states that might unify, it’s a roundabout way of getting all engine manufacturers to conform to EPA’s commitment.

– Divide and conquer. The Kenworth Truck division of Paccar has submitted a proposal to the EPA asking that some of the hardest-to-meet conditions dictated by the upcoming emissions regulations be identified, and then, through engine controls, be permitted outside the regulatory terms.

Assistant chief engineer Dan Farmer cites the operation of high-horsepower engines, under extreme load at high ambient temperatures and elevations, as the sort of exceptionally rigorous operating environment that make the rules tough to meet.

If engines running at these extreme corners of the emissions box could be allowed to go to a different fuel strategy to cover these operating conditions, the performance desired by the EPA could be met over most of the operating range without forcing truck manufacturers into big radiators and energy-robbing accessories. This would, on balance, result in lower emissions overall-a win-win for the industry and the environment.

Is the EPA listening? While this and other petitions have been received by the agency, the lack of response or action has been frustrating. And all the while, the clock is ticking.