At a meeting with the trucking press, Cummins said that cooled EGR is what it believes will enable heavy-duty truck diesel engines to meet the 2.5-grams oxides of nitrogen (NOx) plus non-methane hydrocarbon (NMHC) levels stipulated by the Environmental Protection Agency for 2002.
“Cooled EGR breaks us away from the traditional tradeoff between lower emission levels and high fuel consumption,” said John Wall, vp & CTO of Cummins.
“NOx control is pretty straightforward – it is all about temperature control,” Wall explained. “Control peak combustion temperature and you control the level of NOx emissions – the lower the temperature, the lower the NOx emissions.”
However, Wall said, the technology needed to do that gets pretty complicated. He said that if you retard the thermal efficiency of the engine too much, it worsens fuel efficiency.
Designing and building an engine that can produce the results has taken a lot of work – the company has operated cooled EGR-equipped test trucks over 1.5-million miles nationwide over the last 2 years – and the engines will be more expensive, too.
For Class 8 trucks, Cooled EGR-equipped engines may cost between $1,800 to $3,000 more than current models, said Thomas Kieffer, executive director of marketing. Medium duty fleets may see up to a $1,500 extra charge, he added. Engine weight will also increase – going up 100 to 120 lbs. in heavy-duty engines and 80 lbs. in medium-duty models.
Cummins believes it will be ready to start building these cooled EGR engines on the production line in the next three months, making them available to the marketplace in substantial numbers by March of 2002.
The real issue for Cummins, however, is making sure the industry sticks to the 2002 emission-level mandates. The company plans to fight vigorously any effort to change or extend those emission requirements, largely because it could stand to lose any ability to recoup its investment in this new technology if the rules of the emission game are changed.
“The costs associated with developing and refining the technology required to meet these ambitious NOx emissions reductions have been significant enough to alter the competitive landscape if any compliance delays are granted,” said Tim Solso, Cummins chairman and CEO.
“Cummins has worked hard to meet the requirements of the consent decree. It is critical that the EPA enforce industry-wide compliance with the letter and the spirit of the consent decree to ensure that the full range of environmental and consumer benefits are achieved,” he added.