Emissions Reduction in Transit Buses: Westchester County's Proactive Approach

Sandoval, Jairo A.; Wayne, W. Scott; Posada, Francisco; Schiavone, John J; Pigman, Edward; Bluestone, Michael; Rudd, Robert L.; Stanton, Henry J.; Pereira, Ray; D'Amore, Jerry

doi:10.5399/osu/jtrf.47.3.2136

Cited by 4 publications

(5 citation statements)

References 8 publications

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“…Each certification level reduced NOx emissions roughly in half from the previous certification level, and 2010 SCR NOx aftertreatment effectively reduced NOx to near detection levels at many engine operating modes. The exception is the 2008 hybrid bus, which had emissions similar to a pre-2007 bus, a possible effect of hybridization that has been observed before [8]. Figure 14 shows the MAN cycle NOx emissions from each bus.…”

Section: Discussionmentioning

confidence: 95%

“…operating conditions [7]. Yanowitz and McCormick reviewed all available data and tried to relate differences in the effect of biodiesel on NOx to specific engines and fuel injection technologies [8]. They concluded that biodiesel could increase or reduce NOx emissions depending upon engine technology and driving cycle, and that there were inadequate data to determine an average effect.…”

Section: Introductionmentioning

confidence: 99%

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Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity

Lammert¹,

McCormick²,

Sindler³

et al. 2012

SAE Int. J. Fuels Lubr.

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The objective of this research project was to compare the emissions of oxides of nitrogen (NOx) from transit buses on as many as five different fuels and three standard transit duty cycles to establish if there is a real-world biodiesel NOx increase for transit bus duty cycles and engine calibrations. Prior studies have shown that B20 can cause a small but significant increase in NOx emissions for some engines and duty cycles. Six buses spanning engine build years 1998 to 2011 were tested on the National Renewable Energy Laboratory's Renewable Fuels and Lubricants research laboratory's heavy-duty chassis dynamometer with certification diesel, certification B20 blend, low aromatic [California Air Resources Board (CARB)] diesel, low aromatic B20 blend, and B100 fuels over the Manhattan, Orange County and UDDS test cycles. The buses selected represented the majority of the current national transit fleet as well as including hybrid and selective catalyst reduction (SCR) systems that are increasing penetration in the fleet.The engine emissions certification level had the dominant effect on NOx, with the kinetic intensity of the tested duty cycle being the secondary driving factor. The biodiesel effect on NOx emissions was not statistically significant for most buses and duty cycles for blends with certification diesel, with the exception being a 2008 model year bus. CARB fuel had many more instances of a statistically significant effect of biodiesel increasing NOx. SCR systems proved effective at reducing NOx to near the detection limit on all duty cycles and fuels, including B100. A hybrid system proved to significantly increase NOx emissions over a same model year bus with a conventional drivetrain and the same engine. As all but one test bus were equipped with diesel particulate filter aftertreatment PM emissions were negligible and trends could not be drawn. On the oldest sample bus without aftertreatment PM emissions were reduced with B20 blends. Fuel economy was not significantly changed by engine certification level except that the 2008 conventional bus had the best performance on all cycles while all other buses had very similar results on each cycle. All buses had lower fuel economy with increased kinetic intensity of the cycle.

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Section: Discussionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity

Lammert¹,

McCormick²,

Sindler³

et al. 2012

SAE Int. J. Fuels Lubr.

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“…In general, one can estimate about $12 per horsepower. A retrofit for a diesel engine is described by the EPA as, any technology that when applied to an existing system reduces the emissions beyond that which is currently required by EPA regulations upon certification [40]. A detailed list of retrofit systems, manufactures, and verification data can be found on the EPA and CARB websites.…”

Section: Diesel Oxidation Catalystmentioning

confidence: 99%

“…Heavier duty diesel engines have a greater PM load, which leads to problems with running a DPF [12]. It should also be mentioned that DPF units have little effect on total NOx levels [40]. DPF units must be maintained and periodically cleaned as overtime there is some PM that will not burn off during regeneration.…”

Section: Diesel Particulate Filtermentioning

confidence: 99%

“…DPF units must be maintained and periodically cleaned as overtime there is some PM that will not burn off during regeneration. Ash also accumulates on the filter due to inorganic calcium sulfate and zinc phosphate stemming from the engine lubrication oil [40]. Directing compressed air through the filter itself will work, as well as, typical cleaning, or returning to the manufacturer for cleaning.…”

Section: Diesel Particulate Filtermentioning

confidence: 99%

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Development and commissioning of a small engine test cell

Brown¹

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Development and Commissioning of a Small Engine Test Cell Jacob R. Brown For the purposes of providing the Center for Alternative Fuels, Engines, and Emissions (CAFEE) of West Virginia University (WVU) with the ability to perform engine dynamometer and emissions testing on small engines in the range of 40 horsepower or less, a new test cell was built and commissioned within the CAFEE annex facility in the Morgantown Industrial Park in Westover, WV. The test cell was designed to be used with existing CAFEE emission testing equipment. Test cell commissioning demonstrated the ability of the system to properly operate full steady state test cycles, as well as capture steady state continuous gaseous emissions data and gravimetric particulate matter data. During steady state tests, which followed the ISO-8178 test cycle, the dynamometer showed the capability of holding engine speed within 2% of the reference set point value, and within 1% on a mean basis. Similarly, setpoint reference torque loads between 10 and 60 ft-lbs, which were based on a full map of the test engine, the dynamometer was able to hold torque within 2% of the reference value, for each point and within 1% on a mean basis. A series of steady state tests performed on a 4 cylinder Isuzu CP201 Transport Refrigeration Unit (TRU) diesel engine resulted in baseline engine out emissions data (g/bhp-hr) for HC, CO, CO2, NOx, and PM of 4.31, 2.71, 751.98, 7.33, and 0.591 respectively. Controlled emissions results, with an exhaust aftertreatment Diesel Particulate Filter (DPF) containing an internal catalyst layer, resulted in reduction in HC, CO, and PM of 81, 84, and 86% respectively. The reduction in PM of 86% by the DPF was within the requirements of the California Air Resources Board (CARB) Low Emission TRU (LETRU) Level 2 PM reduction requirement for Verified Diesel Emission Control Strategies (VDECS). iii Acknowledgements I would like to extend my thanks to all of those who made the process of my graduate studies possible, memorable, and most importantly, enjoyable. First, I would like to thank Dr. Scott Wayne for giving me the opportunity to pursue my degree under his advisement. I would also like to thank my committee members, Dr. Andrew Nix, and Dr. Hailin Li for their constant and open support during this process. A sincere thank you to Richard Atkinson, whose contributions made the electrical and data acquisition aspect of my project possible, and whose musings and teachings will never be forgotten. Thanks also, to all the CAFEE members at Westover who made this journey possible. A special thank you to my Mother and Father for always being there for me, and providing me with the teachings, guidance, and support that have brought me so far in my life. I would not be who I am now if it were not for you both. Thank you Lucas Brown, for being the best brother and friend anyone could ask for. Thank you especially Lemma McLean, for your caring support and encouragement. To all my friends, thank you, I am so fortunate to have so many of you. Thanks Balaji ...

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Occupancy and GHG emissions: thresholds for disruptive transportation modes and emerging technologies

Soukhov

Mohamed

2022

Transportation Research Part D: Transport and Environment

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Emissions Reduction in Transit Buses: Westchester County's Proactive Approach

Cited by 4 publications

References 8 publications

Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity

Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity

Development and commissioning of a small engine test cell

Occupancy and GHG emissions: thresholds for disruptive transportation modes and emerging technologies

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Emissions Reduction in Transit Buses: Westchester County's Proactive Approach

Cited by 4 publications

References 8 publications

Effect of B20 and Low Aromatic Diesel on Transit Bus NOx Emissions Over Driving Cycles with a Range of Kinetic Intensity

Effect of B20 and Low Aromatic Diesel on Transit Bus NOx Emissions Over Driving Cycles with a Range of Kinetic Intensity

Development and commissioning of a small engine test cell

Occupancy and GHG emissions: thresholds for disruptive transportation modes and emerging technologies

Contact Info

Product

Resources

About

Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity

Effect of B20 and Low Aromatic Diesel on Transit Bus NO_x Emissions Over Driving Cycles with a Range of Kinetic Intensity