Evaluating real-world emissions from in-use buses and taxis using on-road remote sensing

Middela, Mounisai Siddartha; Mahesh, S.; McNabola, Aonghus; Smith, William; Timoney, David; Ekhtiari, Ali; Fowler, Ben; Willis, Paul; Rose, Rebecca

doi:10.1016/j.envpol.2023.123241

Evaluating real-world emissions from in-use buses and taxis using on-road remote sensing

Title

Evaluating real-world emissions from in-use buses and taxis using on-road remote sensing

Author

Middela, Mounisai Siddartha (Trinity College Dublin)
Mahesh, S. (TU Delft Transport and Planning)
McNabola, Aonghus (Trinity College Dublin)
Smith, William (University College Dublin)
Timoney, David (University College Dublin)
Ekhtiari, Ali (University College Dublin)
Fowler, Ben (Ricardo Energy and Environment)
Willis, Paul (Ricardo Energy and Environment)
Rose, Rebecca (Ricardo Energy and Environment)

Date

2024

Abstract

Assessing real-world emissions from buses and taxis is vital to comprehend their impact on urban air quality. Such vehicles differ significantly from the majority of the fleet owing to their higher mileage rates. However, few studies have focused on specifically assessing the emissions from this segment of the vehicle fleet. In this context, this study evaluated the real-world emissions of nitrogen oxides (NO_x) from in-use buses and taxis in Dublin, Ireland, using crossroad remote sensing technology. The remote sensing system was deployed at strategic locations throughout the city to capture on-road emissions from passing vehicles. The collected data included vehicle related information such as emission standard, make, and mileage, and pollutants including NO_x. Based on this data, analysis was aimed to understand the impact of Euro emission standard, ambient temperature, mileage, and make of the vehicle on NO_x emissions. The results reveal that the average emissions from taxis reduce by 37% from Euro 5 to Euro 6b, and average emissions from Euro 6 buses are 87% lower compared to Euro 5. The trends in emission factors (EFs) of buses and taxis were similar during summer and winter sampling. Moreover, on comparing the emissions from the top five taxi manufacturers, different trends in the emission factors were observed. Finally, the study found that the effect of vehicle mileage on emissions was unclear for both buses and taxis. In any case, these findings provide valuable insights into the real-world emission performance of the existing fleet of buses and taxis in Dublin and highlight the need for targeted measures to reduce emissions from these vehicles. The results can assist policymakers and urban planners in formulating evidence-based strategies to improve air quality in Dublin and other cities facing similar challenges.

Subject

Buses
Euro-6 regulation
In-use surveillance
On-road vehicle emissions
Remote sensing
Taxis

To reference this document use:

http://resolver.tudelft.nl/uuid:d4c2f44f-2429-4c7a-835b-9792e58541e2

DOI

https://doi.org/10.1016/j.envpol.2023.123241

Embargo date

2024-07-08

ISSN

0269-7491

Source

Environmental Pollution, 344

Bibliographical note

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Part of collection

Institutional Repository

Document type

journal article

Rights

Files

file embargo until 2024-07-08