Cummins Inc. announced that it will not use selective catalytic reduction (SCR) technology — which requires the use of urea — to meet the EPA 2010 emissions regulations for heavy-duty diesel engines. However, the company said it would meet the EPA 2010 regs for medium-duty engines by using SCR.
“SCR is a good solution for mid-range vehicles, but heavy-duty customer requirements are different,” stated Steve Charlton, executive director of heavy-duty engineering, “Our 2010 heavy-duty solution requires no NOx aftertreatment,” he stressed. “For EPA '07, we used cooled EGR [exhaust gas recirculation] and a DPF [diesel particulate filter] and crankcase ventilation, and we will use [these technologies] in 2010. There will be very little change in the architecture.”
Charlton said “key enablers” that will allow the engine maker to meet both the heavy-duty emissions regs and the customer requirement of lowest cost of ownership without SCR include “highly capable” base engines and the XPI fuel system, as well as Cummins' combustion technology, air technology, electronic controls and particulate filter.
According to Cummins, the heavy-duty 2010 solution will be an “X family engine” and will be offered in 15L as well as new 11.9- and 16L displacement versions. While these 2010 engines were not officially designated as ISX models, it was noted that the heavy-duty ISM engine will be “retired from the North American highway market” in 2010.
Specific items about the development of the heavy-duty engines noted by Charlton include the expectation there should only be a “small increase in heat rejection — nothing the OEMs can't handle — and there should be no significant packaging challenges.” He said the “alpha build” for these engines will begin in the first quarter of next year.
Commenting on a top concern of many over-the-road fleets, vp-sales Jeff Jones said “Longhaul fleets will breathe a sigh of relief that they will not have to worry about [buying] urea on the road” if they buy an EPA 2010 Cummins heavy-duty engine.
As for Cummins' medium-duty path to meeting EPA 2010, Jeff Weikert, executive director of mid-range engineering, explained that SCR will be added to the cooled EGR and DPF that are used to meet EPA '07 regs. “SCR requires a urea tank [on board the truck] and a urea dosing unit,” said Weikert. He added that keeping the urea topped up should not be a major issue for medium-duty truck operations as their vehicles typically return to a domicile regularly and run at mileage levels that would allow urea fill-ups to track with scheduled maintenance intervals.
Weikert pointed out that Cummins is experienced with SCR as it has used this technology to meet Euro IV and Euro V emissions regulations on engines sold overseas. “We feel the key will be not just delivering this [mid-range] solution, but delivering it on time” for North American customers.
Cummins also announced that beginning January 1, 2008, all its on-highway products will meet the new California Air Resource Board (CARB) idle-reduction regulation. Specifically, the Cummins ISX, ISM, ISL, ISC and ISB engines will be “Clean Idle” certified “generating NOx emissions of less than 30 grams per hour, so they “will be allowed to idle indefinitely” under the new rule.