Real-Driving Emissions of an Aging Biogas-Fueled City Bus
Transition to low emission transportation and cleaner cities requires a broad introduction of low- and zero-carbon alternatives to conventional petrol- and diesel-powered vehicles. New-generation gas buses are a cost-effective way to reduce local air pollutants from urban transportation. Moreover, m...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-10-01
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| Series: | Clean Technologies |
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| Online Access: | https://www.mdpi.com/2571-8797/4/4/59 |
| _version_ | 1797460790267084800 |
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| author | Kirsi Spoof-Tuomi Hans Arvidsson Olav Nilsson Seppo Niemi |
| author_facet | Kirsi Spoof-Tuomi Hans Arvidsson Olav Nilsson Seppo Niemi |
| author_sort | Kirsi Spoof-Tuomi |
| collection | DOAJ |
| description | Transition to low emission transportation and cleaner cities requires a broad introduction of low- and zero-carbon alternatives to conventional petrol- and diesel-powered vehicles. New-generation gas buses are a cost-effective way to reduce local air pollutants from urban transportation. Moreover, major greenhouse gas (GHG) savings may be achieved using biogas as the power source. The main objective of this research was to investigate CH<sub>4</sub> and other gaseous emissions of a biogas-fueled urban bus equipped with a three-way catalyst (TWC) in real-world conditions. The study focused on emissions from a six-year-old gas-powered city bus, supplementing emission data from aging bus fleets. Impaired CH<sub>4</sub> oxidation and NO<sub>x</sub> reduction were observed in the catalyst after its service life of 375,000 km–400,000 km. The main reason for low CH<sub>4</sub> and NO<sub>x</sub> conversion over the TWC was concluded to be the partial deactivation of the catalyst. Another critical issue was the fluctuating air-to-fuel ratio. The results show that the efficiency of exhaust after-treatment systems should be closely monitored over time, as they are exposed to various aging processes under transient driving conditions, leading to increased real-world emissions. However, the well-to-wheels (WTW) analysis showed that an 80% GHG emission benefit could be achieved by switching from diesel to biomethane, giving a strong environmental argument for biogas use. |
| first_indexed | 2024-03-09T17:11:10Z |
| format | Article |
| id | doaj.art-2d30c39a3b57406da22b6848c3a1f600 |
| institution | Directory Open Access Journal |
| issn | 2571-8797 |
| language | English |
| last_indexed | 2024-03-09T17:11:10Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Clean Technologies |
| spelling | doaj.art-2d30c39a3b57406da22b6848c3a1f6002023-11-24T14:04:26ZengMDPI AGClean Technologies2571-87972022-10-014495497110.3390/cleantechnol4040059Real-Driving Emissions of an Aging Biogas-Fueled City BusKirsi Spoof-Tuomi0Hans Arvidsson1Olav Nilsson2Seppo Niemi3School of Technology and Innovations, University of Vaasa, Box 700, FI-65101 Vaasa, FinlandRISE Research Institutes of Sweden, Box 5053, SE-90403 Umeå, SwedenSchool of Technology and Innovations, University of Vaasa, Box 700, FI-65101 Vaasa, FinlandSchool of Technology and Innovations, University of Vaasa, Box 700, FI-65101 Vaasa, FinlandTransition to low emission transportation and cleaner cities requires a broad introduction of low- and zero-carbon alternatives to conventional petrol- and diesel-powered vehicles. New-generation gas buses are a cost-effective way to reduce local air pollutants from urban transportation. Moreover, major greenhouse gas (GHG) savings may be achieved using biogas as the power source. The main objective of this research was to investigate CH<sub>4</sub> and other gaseous emissions of a biogas-fueled urban bus equipped with a three-way catalyst (TWC) in real-world conditions. The study focused on emissions from a six-year-old gas-powered city bus, supplementing emission data from aging bus fleets. Impaired CH<sub>4</sub> oxidation and NO<sub>x</sub> reduction were observed in the catalyst after its service life of 375,000 km–400,000 km. The main reason for low CH<sub>4</sub> and NO<sub>x</sub> conversion over the TWC was concluded to be the partial deactivation of the catalyst. Another critical issue was the fluctuating air-to-fuel ratio. The results show that the efficiency of exhaust after-treatment systems should be closely monitored over time, as they are exposed to various aging processes under transient driving conditions, leading to increased real-world emissions. However, the well-to-wheels (WTW) analysis showed that an 80% GHG emission benefit could be achieved by switching from diesel to biomethane, giving a strong environmental argument for biogas use.https://www.mdpi.com/2571-8797/4/4/59real-driving emissionportable emission measurement systemEuro VIurban buscatalyst deactivationcompressed biogas |
| spellingShingle | Kirsi Spoof-Tuomi Hans Arvidsson Olav Nilsson Seppo Niemi Real-Driving Emissions of an Aging Biogas-Fueled City Bus Clean Technologies real-driving emission portable emission measurement system Euro VI urban bus catalyst deactivation compressed biogas |
| title | Real-Driving Emissions of an Aging Biogas-Fueled City Bus |
| title_full | Real-Driving Emissions of an Aging Biogas-Fueled City Bus |
| title_fullStr | Real-Driving Emissions of an Aging Biogas-Fueled City Bus |
| title_full_unstemmed | Real-Driving Emissions of an Aging Biogas-Fueled City Bus |
| title_short | Real-Driving Emissions of an Aging Biogas-Fueled City Bus |
| title_sort | real driving emissions of an aging biogas fueled city bus |
| topic | real-driving emission portable emission measurement system Euro VI urban bus catalyst deactivation compressed biogas |
| url | https://www.mdpi.com/2571-8797/4/4/59 |
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