A Fast Method for Estimating the Emission Factors of Air Pollutants from In-Use Vehicles Fleet

The real-world emission factors of gaseous and particulate air pollutants emitted from in-use vehicles, can be rapidly estimated using monitoring data of their concentration profiles from inside roadway tunnels using a mobile laboratory equipped with fast monitoring instruments. The concentrations of CO2 and particle-bound polycyclic aromatic hydrocarbons (PM-PAHs) and NOx, were observed to increase linearly with traveling distance inside two successive roadway tunnels: the Hongjimun Tunnel and the Jeongneung Tunnel on the Naebu Express Way in Seoul, Korea, except for a small region of decrease. In the decreasing regions, within a few hundred meters of the entrance and before the exit, outside background air with low concentrations of air pollutants was thought to have intruded. From the slopes of the linear regression between distance and concentrations, a fleet-averaged (light-, medium-, and heavy-duty vehicles with 54%, 36%, and 10%, respectively) emission factor of CO2, PM-PAHs, and NOx at an average speed of ~60 km h−1 could be calculated as 197 ± 38 g km−1, 4.2 ± 0.8 × 10−4 g km−1, and 0.530 ± 0.230 g km−1, respectively, which are within the ranges of values reported in the literature. For each tunnel, the emission factors of CO2, PM-PAHs, and NOx estimated on days with higher-than-normal fractions of heavy-duty vehicles, were higher than those on other days. From these results, the new fast method proposed in this study is considered useful for estimating real-world emission factors of air pollutants by using a mobile laboratory as a complementary tool to traditional tunnel studies. This method can be used to rapidly make emission maps at roadway tunnels in mega-cities like Seoul, Korea, for urban air-quality management.

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Real-World Emission Factors for Antimony and Other Brake Wear Related Trace Elements: Size-Segregated Values for Light and Heavy Duty Vehicles

Environmental Science & Technology ◽

10.1021/es9006096 ◽

2009 ◽

Vol 43 (21) ◽

pp. 8072-8078 ◽

Cited By ~ 80

Author(s):

Nicolas Bukowiecki ◽

Peter Lienemann ◽

Matthias Hill ◽

Renato Figi ◽

Agnes Richard ◽

...

Keyword(s):

Trace Elements ◽

Real World ◽

Emission Factors ◽

Heavy Duty ◽

Brake Wear ◽

Heavy Duty Vehicles

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Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15020304 ◽

2018 ◽

Vol 15 (2) ◽

pp. 304 ◽

Cited By ~ 29

Author(s):

Barouch Giechaskiel

Keyword(s):

Solid Particle ◽

Particle Number ◽

Emission Factors ◽

Heavy Duty ◽

The Road ◽

On The Road ◽

Heavy Duty Vehicles

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Variability in Real-World Activity Patterns of Heavy-Duty Vehicles by Vocation

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198119844247 ◽

2019 ◽

Vol 2673 (9) ◽

pp. 51-61 ◽

Cited By ~ 1

Author(s):

George Scora ◽

Kanok Boriboonsomsin ◽

Thomas D. Durbin ◽

Kent Johnson ◽

Seungju Yoon ◽

...

Keyword(s):

Real World ◽

Motor Vehicle ◽

Activity Patterns ◽

Geographical Area ◽

Food Distribution ◽

Vehicle Emission ◽

Heavy Duty ◽

Mobile Source ◽

Vehicle Activity ◽

Heavy Duty Vehicles

Vehicle activity is an integral component in the estimation of mobile source emissions and the study of emission inventories. In the Environmental Protection Agency’s (EPA’s) Motor Vehicle Emission Simulator (MOVES) model and the California Air Resources Board’s (CARB’s) Emission Factor (EMFAC) model, vehicle activity is defined for source types, in which vehicles within a source type are assumed to have the same activity. In both of these models, source types for heavy-duty vehicles are limited in number and the assumption that the activity within these source types is similar may be inaccurate. The focus of this paper is to improve vehicle emission estimates by improving characterization of heavy-duty vehicle activity using vehicle vocation. This paper presents results and analysis from the collection of real-world activity data of 90 vehicles from 19 vehicle categories made up from a combination of vehicle vocation, gross vehicle weight, and geographical area— namely, line haul—out of state; line haul—in state; drayage—Northern California; drayage—Southern California; agricultural—Southern Central Valley; heavy construction; concrete mixers; food distribution; beverage distribution; local moving; airport shuttle; refuse; urban buses; express buses; freeway work; sweeping; municipal work; towing; and utility repair. Results show that real-world activity patterns of heavy-duty vehicles vary greatly by vocation and in some cases by geographic region. Vocation-specific activity information can be used to update assumptions in EPA’s MOVES model or CARB’s EMFAC model to address this variability in emission inventory development.

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A new method to determine exhaust emission factors for heavy duty vehicles

The Science of The Total Environment ◽

10.1016/0048-9697(95)04650-p ◽

1995 ◽

Vol 169 (1-3) ◽

pp. 213-217 ◽

Cited By ~ 5

Author(s):

P. Jost ◽

D. Hassel ◽

K.S. Sonnborn

Keyword(s):

Emission Factors ◽

New Method ◽

Exhaust Emission ◽

Heavy Duty ◽

Heavy Duty Vehicles

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Real-World Emissions of Euro VI Heavy-Duty Vehicles

10.4271/2021-01-5074 ◽

2021 ◽

Author(s):

Pablo Mendoza Villafuerte ◽

Joachim Demuynck ◽

Dirk Bosteels ◽

Robin Vermeulen ◽

Rene van Gijlswijk ◽

...

Keyword(s):

Real World ◽

Heavy Duty ◽

Heavy Duty Vehicles

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Characterization of Real-World Pollutant Emissions and Fuel Consumption of Heavy-Duty Diesel Trucks with Latest Emissions Control

Atmosphere ◽

10.3390/atmos10090535 ◽

2019 ◽

Vol 10 (9) ◽

pp. 535 ◽

Cited By ~ 1

Author(s):

Christos Keramydas ◽

Leonidas Ntziachristos ◽

Christos Tziourtzioumis ◽

Georgios Papadopoulos ◽

Ting-Shek Lo ◽

...

Keyword(s):

Fuel Consumption ◽

Real World ◽

Emission Factors ◽

Pollutant Emissions ◽

Particulate Filter ◽

Emission Measurement ◽

Heavy Duty ◽

Heavy Duty Diesel ◽

Diesel Trucks ◽

The Impact

Heavy-duty diesel trucks (HDDTs) comprise a key source of road transport emissions and energy consumption worldwide mainly due to the growth of road freight traffic during the last two decades. Addressing their air pollutant and greenhouse gas emissions is therefore required, while accurate emission factors are needed to logistically optimize their operation. This study characterizes real-world emissions and fuel consumption (FC) of HDDTs and investigates the factors that affect their performance. Twenty-two diesel-fueled, Euro IV to Euro VI, HDDTs of six different manufacturers were measured in the road network of the Hong Kong metropolitan area, using portable emission measurement systems (PEMS). The testing routes included urban, highway and mixed urban/highway driving. The data collected corresponds to a wide range of driving, operating, and ambient conditions. Real-world distance- and energy-based emission levels are presented in a comparative manner to capture the effect of after-treatment technologies and the role of the evolution of Euro standards on emissions performance. The emission factors’ uncertainty is analyzed. The impact of speed, road grade and vehicle weight loading on FC and emissions is investigated. An analysis of diesel particulate filter (DPF) regenerations and ammonia (NH3) slip events are presented along with the study of Nitrous oxide (N2O) formation. The results reveal deviations of real-world HDDTs emissions from emission limits, as well as the significant impact of different operating and driving factors on their performance. The occasional high levels of N2O emissions from selective catalytic reduction equipped HDDTs is also revealed, an issue that has not been thoroughly considered so far.

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Exhaust emission factors of greenhouse gases (GHGs) from European road vehicles

Environmental Sciences Europe ◽

10.1186/s12302-020-00407-5 ◽

2020 ◽

Vol 32 (1) ◽

Author(s):

Michaël Clairotte ◽

Ricardo Suarez-Bertoa ◽

Alessandro A. Zardini ◽

Barouch Giechaskiel ◽

Jelica Pavlovic ◽

...

Keyword(s):

Greenhouse Gases ◽

Greenhouse Gas ◽

Greenhouse Gas Emission ◽

Emission Factors ◽

Research Centre ◽

Transport Sector ◽

Heavy Duty ◽

Light Duty ◽

Light Duty Vehicles ◽

Heavy Duty Vehicles

Abstract Background Road transport is an important contributor to the European Union’s total greenhouse gas emissions. This study aims at summarizing methane (CH4) and nitrous oxide (N2O) exhaust emissions from L-category, light-duty and heavy-duty vehicles in the European Union. The assessment is based on measurements carried out in the Vehicle Emission Laboratory of the Joint Research Centre between 2009 and 2019. The exhaust chemical composition from a fleet of 38 L-category vehicles Euro 1 to Euro 4 (2- and 3-wheelers, small quadricycles such as quads and minicars), 63 light-duty vehicles from Euro 5b to Euro 6d-TEMP (passenger cars, including hybrid vehicles), and 27 light commercial and heavy-duty vehicles from pre-Euro I to Euro VI (including lorries, buses and garbage trucks) was analyzed by Fourier-transform infrared spectroscopy. Results CH4 emission factors monitored were from 1 to 234 mg/km for L-category vehicles (mean: 39 mg/km), from 0.1 to 40 mg/km for light-duty vehicles (mean: 7 mg/km), and from non-detectable to 320 mg/km for heavy-duty vehicles (mean: 19 mg/km). N2O emission factors monitored were from non-detectable to 5 mg/km for L-category vehicles (mean: 1 mg/km), from non-detectable to 40 mg/km for light-duty vehicles (mean: 7 mg/km), and from non-detectable to 118 mg/km for heavy-duty vehicles (mean: 19 mg/km). According to the 100-year Global Warming Potential of these greenhouse gases, these emissions corresponded to a range from negligible up to 9 g/km of CO2-equivalent for CH4 and from negligible up to 32 g/km of CO2-equivalent for N2O. Conclusions The higher contributors of CH4 were the two-stroke mopeds included in the L-category vehicles, while the higher emissions of N2O were found in the modern (Euro 5–6 or Euro V–VI) diesel light- and heavy-duty vehicles. Among them, vehicles complying with Euro 6 and Euro VI standard were associated to higher N2O emissions compared to those associated to Euro 5 and pre-Euro IV standards, which could be attributed to the introduction of the after-treatment systems designed to fulfill more stringent NOx standards. These updated emission factors and unique on its kind database represent a source of information for legislators and modelers to better assess the greenhouse gas emission reduction in the EU transport sector.

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Mobile laboratory measurements of black carbon, polycyclic aromatic hydrocarbons and other vehicle emissions in Mexico City

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-5-7387-2005 ◽

2005 ◽

Vol 5 (4) ◽

pp. 7387-7414 ◽

Cited By ~ 4

Author(s):

M. Jiang ◽

L. C. Marr ◽

E. J. Dunlea ◽

S. C. Herndon ◽

J. T. Jayne ◽

...

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Black Carbon ◽

Mexico City ◽

Aromatic Hydrocarbons ◽

Emission Inventory ◽

Emission Factors ◽

Motor Vehicles ◽

Mobile Laboratory ◽

Exhaust Plumes ◽

Polycyclic Aromatic

Abstract. Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are of concern due to their effects on climate and health. The main goal of this research is to provide the first estimate of emissions of BC and particle-phase PAHs (PPAHs) from motor vehicles in Mexico City. The emissions of other pollutants including carbon monoxide (CO), oxides of nitrogen (NOx), volatile organic compounds (VOCs), and particulate matter of diameter 2.5 µm and less (PM2.5) are also estimated. As a part of the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003), a mobile laboratory was driven throughout the city. The laboratory was equipped with a comprehensive suite of gas and particle analyzers, including an aethalometer that measured BC and a photoionization aerosol sensor that measured PPAHs. While driving through traffic, the mobile lab is continuously sampling exhaust plumes from the vehicles around it. We have developed a method of automatically identifying exhaust plumes, which are then used as the basis for calculation of fleet-average emission factors. In the approximately 75 h of on-road sampling during the field campaign, we have identified ~30 000 exhaust measurement points that represent a variety of vehicle types and driving conditions. The large sample provides a basis for estimating fleet-average emission factors and thus the emission inventory. Motor vehicles in the Mexico City area are estimated to emit 1700±200 metric tons BC, 57±6 tons PPAHs, 1 190 000±40 000 tons CO, 120 000±3000 tons NOx, 202 000±4000 tons VOCs, and 4400±400 tons PM2.5 per year, not including cold start emissions. The estimates for CO, NOx, and PPAHs may be low by up to 10% due to the slower response time of analyzers used to measure these species. Compared to the government's official motor vehicle emission inventory for the year 2002, the estimates for CO, NOx, VOCs, and PM2.5 are 38% lower, 23% lower, 7% higher, and 26% higher, respectively. The distributions of emission factors of BC, PPAHs, and PM2.5 are highly skewed, i.e. asymmetric, while those for benzene, measured as a surrogate for total VOCs, and NOx are less skewed. As a result, the total emissions of BC, PPAHs, and PM2.5 could be reduced by approximately 50% if the highest 20% of data points were removed, but ''super polluters'' are less influential on overall NOx and VOC emissions.

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