Study Finds Environmental and Tailpipe Pollutants Benefits in Using Biodiesel in Construction Vehicles

Green Car Congress, July 19, 2009

Using biodiesel in construction vehicles offers promising environmental benefits in terms of reduced tailpipe emissions as well as reductions in fuel cycle emissions of selected pollutants, according to a new study by researchers at North Carolina State University. A paper on their work was published July 16 in the ACS journal Environmental Science & Technology.
The researchers developed an updated and modified life cycle inventory (LCI) to estimate fuel cycle energy consumption and emissions of selected pollutants and greenhouse gases. Key improvements in the LCI included an update of combusion emission factors based on 2006 US national average emission rates; comparison of pre-NSPS (New Source Performance Standards) and NSPS-compliant soyoil plants; and the use of portable emission measurements system (PEMS) data for real-world tailpipe emissions factors based on 15 nonroad diesel vehicles: five backhoes, four front-end loaders, and six motor graders.
Vehicle emissions scenarios included: baseline petroleum diesel (PD) in-use measurement data based on PEMS; estimated B20 vehicle emissions based on EPA's engine dynamometer data; and estimated B20 vehicle emissions based on NREL's chassis dynamometer data.
Life cycle fossil energy reductions are estimated at 9% for B20 and 42% for B100 versus petroleum diesel based on the current national energy mix. Fuel cycle emissions will contribute a larger share of total life cycle emissions as new engines enter to the in-use fleet.
Seven scenarios were use in the LCI analysis.
Read More