The Transient Nature of Particle Emissions from Light Duty Hybrid Vehicles Lisa A. Graham Environmental Technology Centre, Environment Canada 335 River Road, K1A 0H3 Ottawa, Ontario, Canada Martha Christenson Department of Civil and Environmental Engineering, Carleton University 1125 Colonel By Drive, K1S 5B6 Ottawa, Ontario, Canada
The Light Duty Hybrid Project Four light duty gasoline-electric hybrid vehicles tested over 5 driving cycles at 20 o C and -18 o C The hybrid vehicles: Honda Civic 2003 Honda Insight 2000 Ford Escape 2005 Toyota Prius 2004 The 2002 gasoline Smart Car
Facility
The Light Duty Hybrid Project 4-phase Federal Test Procedure (FTP) 4-phase LA92 Represents real-world driving behaviour with more transients and higher speeds than the FTP New York City Cycle (NYCCx2) Congested urban driving conditions US06x2 Aggressive, high speed driving conditions Highway fuel consumption test (HWFCT) Free-flow highway driving conditions
Integrated Sampling PM PM 2.5 mass emissions Teflo filter media PM 2.5 Organic and elemental carbon emissions Quartz filter media with artifact correction scheme Criteria Emissions CO, NO x,thc, NMHC, NMOG Green house gas emissions CO 2, N 2 O, CH 4
Transient Sampling Total particle number emissions Condensation Particle Counter (CPC) Particle size distributions Electrical Low Pressure Impactor (ELPI) Modal (second by second) gaseous emissions CO 2, CO, NO x, THC Hybrid battery state of charge (SOC) Measured for Civic and Insight using Snap-Link OBD scan tool Charging current Measured for Prius and Escape
Fuel Consumption 18 Gasoline SmartCar Toyota Prius Ford Escape Hybrid Honda Insight Honda Civic Hybrid Honda Civic (-18C) 16 Fuel Consumption (L/100km) 14 12 10 8 6 4 2 0 FTP phase 1 FTP phase 2 FTP phase 3 FTP phase 4 LA92 CS1 LA92 CS2 LA92 HS1 LA92 HS2 US06 HWFET NYCC
PM 2.5 Mass Emissions 140 Gasoline SmartCar Toyota Prius Ford Escape Hybrid Honda Insight Hybrid Honda Civic Hybrid Honda Civic (-18C) 120 100 PM2.5 (mg/mile) 80 60 40 20 0 FTP Cold Start FTP Hot Start LA92 Cold Start LA92 Hot Start US06 HWFET NYCC
PM 2.5 Mass Emissions 20 Gasoline SmartCar Toyota Prius Ford Escape Hybrid Honda Insight Hybrid Honda Civic Hybrid Honda Civic (-18C) 18 16 PM2.5 (mg/mile) 14 12 10 8 6 4 2 0 FTP Cold Start FTP Hot Start LA92 Cold Start LA92 Hot Start US06 HWFET NYCC
NYCC Ford Escape Hybrid Speed (mph) Current (dekaa) 30 25 20 15 10 5 0-5 -10 Speed (mph) Current #1 Current #2 Particle Count #1 Particle Count #2 CO2 #1 CO2 #2 0 100 200 300 400 500 600 Time (s) 1.0E+07 1.0E+06 1.0E+05 1.0E+04 1.0E+03 1.0E+02 1.0E+01 1.0E+00 1.0E-01 1.0E-02 1.0E-03 1.0E-04 Log Scale Particles/cm3 CO2 (g/s)
LA92 - Honda Civic Hybrid Speed (mph) Hot Start SOC Hot Start PM Number Concentration Cold Start SOC Cold Start PM Number Concentration Speed (mph) SOC (%) 80 70 60 50 40 30 20 10 0 0 200 400 600 800 1000 1200 1400 Time (s) 1.0E+07 9.0E+06 8.0E+06 7.0E+06 6.0E+06 5.0E+06 4.0E+06 3.0E+06 2.0E+06 1.0E+06 0.0E+00 Particles/cm3
LA92 Toyota Prius Speed (mph) Cold Start #1 Cold Start #2 Hot Start#1 Hot Start #2 Speed (mph) 80 70 60 50 40 30 20 10 0 6.0E+06 5.0E+06 4.0E+06 3.0E+06 2.0E+06 1.0E+06 Particles/cm3-10 0 200 400 600 800 1000 1200 1400 Time (s) 0.0E+00
HWFCT Particle Emissions Speed (mph) SmartCar Ford Escape Hybrid 180 Toyota Prius Honda Civic Hybrid Honda Civic Hybrid (Cold) 1.0E+07 Speed (mph) 160 140 120 100 80 60 40 20 1.0E+06 1.0E+05 1.0E+04 1.0E+03 1.0E+02 1.0E+01 Particles/cm3 0 0 100 200 300 400 500 600 700 Time (s) 1.0E+00
US06 Particle Emissions Speed (mph) SmartCar Ford Escape Hybrid Toyota Prius Honda Civic Hybrid Honda Insight Hybrid Honda Civic Hybrid (Cold) Speed (mph) 120 100 80 60 40 20 0 1.0E+07 9.0E+06 8.0E+06 7.0E+06 6.0E+06 5.0E+06 4.0E+06 3.0E+06 2.0E+06 1.0E+06 0.0E+00 0 200 400 600 800 1000 1200 Time (s) Particles/cm3
Concluding Remarks Patterns in total particle number concentrations from the hybrid vehicles are in some ways similar to conventional vehicles with large increases in concentration on accelerations. Different patterns are observed under driving conditions where the engine is turned off, or the electric drive assists in accelerations. Patterns can vary from one repeat of a test to another depending on battery state of charge.
Concluding Remarks Cold temperatures result in higher mass and number emission rates of particulate matter as compared to standard temperature Cold temperatures influence the transient nature of particle emissions from hybrid vehicles The transient and variable behaviour of light duty hybrid vehicle emissions have implications in emission inventory development
Acknowledgements The authors would like to recognize the efforts of the Environment Canada laboratory staff: drivers, sampling technicians and chemical technologists. Funding provided by: Natural Sciences and Engineering Research Council of Canada (NSERC) Climate Change Technology and Innovation Initiative Program for Energy Research and Development