Diesel research is only one area of transportation research at Argonne. And they will cut pollution levels from diesel smoke at the same time. Argonne transportation analysts estimate that the average U.S. long-haul heavy truck's engine idles up to 1,890 hours a year and burns about one gallon of diesel fuel per idling hour. There are about 480,000 class 7 and 8 trucks on U.S. highways. The payback period for such devices could be as short as one year, depending on use.
Actual savings depend greatly on individual circumstances.