Technical Paper
On Road vs. Off Road Low Load Cycle Comparison
2024-04-09
2024-01-2134
Reducing criteria pollutants while reducing greenhouse gases is an active area of research for commercial on-highway vehicles as well as for off-highway machines. The heavy duty on-highway sector has moved to reducing NOx by 82.5% while increasing the engine useful life from 435,000 to 650,000 miles by 2027 in the United States (US). An additional certification cycle, the Low Load Cycle (LLC), has been added focusing on part load operation having tight NOx emissions levels. In addition to NOx, the total CO2 on the vehicle will also be reduced for various model years. The off-highway market is following with a 90% NOx reduction target along with greenhouse gas targets that are still being established. The off-highway market will also need to certify with a Low Load Application Cycle (LLAC), which has been proposed (back in 2021) for evaluation.