Real-world activity, fuel use, and emissions of diesel side-loader refuse trucks

Abstract

Abstract Diesel refuse trucks have the worst fuel economy of onroad highway vehicles. The real-world effectiveness of recently introduced emission controls during low speed and low engine load driving has not been verified for these vehicles. A portable emission measurement system (PEMS) was used to measure rates of fuel use and emissions on six side-loader refuse trucks. The objectives were to: (1) characterize activity, fuel use, and emissions; (2) evaluate variability between cycles and trucks; and (3) compare results with the MOVES emission factor model. Quality assured data cover 210,000 s and 550 miles of operation during which the trucks collected 4200 cans and 50 tons of waste material. The average fuel economy was 2.6 mpg. Trash collection contributed 70%–80% of total fuel use and emissions. The daily activity Operating Mode (OpMode) distribution and cycle average fuel use and emissions is different from previously used cycles such as Central Business District (CBD), New York Garbage Truck (NYGT), and William H. Martin (WHM). NOx emission rates for trucks with selective catalytic reduction were over 90% lower than those for trucks without. Similarly, trucks with diesel particulate filters had over 90% lower particulate matter (PM) emissions than trucks without. Compared to unloaded trucks, loaded truck averaged 18% lower fuel economy while NOx and PM emissions were higher by 65% and 16%, respectively. MOVES predicted values are highly correlated to empirical data; however, MOVES estimates are 37% lower for NOx and 300% higher for PM emission rates. The data presented here can be used to develop more representative cycles and improve emission factors for side-loader refuse trucks, which in turn can improve the accuracy of refuse truck emission inventories.