Fuel consumption and exhaust emissions of urban buses

Performance of the new diesel technology

Nils-Olof Nylund, Kimmo Erkkilä, Tuukka Hartikka

Research output: Book/ReportReportProfessional

5 Citations (Scopus)

Abstract

The research was carried out by the Finnish Public Transport Association. Altogether seven vehicles were measured, two two-axle Euro 3 -class vehicles as references, three new two-axle Euro 4 -class vehicles and two new three-axle vehicles. The measurements were carried out on a chassis dynamometer, using three cycles describing actual driving. In addition to fuel consumption, exhaust emissions were also recorded for these vehicles. The differences in fuel consumption and operating expenses were after all smaller than first anticipated. In the case of the Euro 3 -class reference vehicles, the difference between the two vehicles was as high as 7-10%. For new two-axle vehicles the difference in fuel consumption, when simulating urban driving, is only 3-4%. Due to different technical solutions, the results were anticipated to be greater. In suburban driving although, the difference is at its most 11%. In the class of two-axle vehicles, lowest fuel consumption was measured for a SCR vehicle, whereas in the case of the two three-axle vehicles, EGR technology resulted in lowest fuel consumption. The measurements do not give an unambiguous answer to whether the EGR- or SCR-technology is preferable regarding fuel consumption. The contemplation is hindered by two factors. On one hand, the order of superiority depends on the driving cycle, on the other, the actual exhaust emissions do not match with expectations. The two EGR vehicles (same make) produced higher NOx -emissions than the manufacturer's Euro 3 -engine. The most fuel efficient SCR -engine is not truly Euro 4 -class what comes to NOx -emissions. Only two of the new vehicles, both with SCR technology, produce NOx -emissions genuinely matching their classes. Both fuel consumption and exhaust emissions have been observed in the study. In case exhaust emissions were completely disregarded, fleet decisions might be directed towards fuel efficient vehicles which after all do not reach the level of emission performance that reasonably could be expected.
Original languageEnglish
Place of PublicationEspoo
PublisherVTT Technical Research Centre of Finland
Number of pages54
ISBN (Electronic)978-951-38-6923-6
ISBN (Print)978-951-38-6922-9
Publication statusPublished - 2007
MoE publication typeNot Eligible

Publication series

NameVTT Tiedotteita - Research Notes
PublisherVTT
No.2373
ISSN (Print)1235-0605
ISSN (Electronic)1455-0865

Fingerprint

Fuel consumption
Axles
Thyristors
Engines
Dynamometers
Chassis

Keywords

  • public transport
  • urban transport
  • vehicles
  • buses
  • diesel engines
  • fuel consumption
  • exhaust emissions
  • performance
  • measurements
  • operating expences

Cite this

Nylund, N-O., Erkkilä, K., & Hartikka, T. (2007). Fuel consumption and exhaust emissions of urban buses: Performance of the new diesel technology. Espoo: VTT Technical Research Centre of Finland. VTT Tiedotteita - Meddelanden - Research Notes, No. 2373
Nylund, Nils-Olof ; Erkkilä, Kimmo ; Hartikka, Tuukka. / Fuel consumption and exhaust emissions of urban buses : Performance of the new diesel technology. Espoo : VTT Technical Research Centre of Finland, 2007. 54 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2373).
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abstract = "The research was carried out by the Finnish Public Transport Association. Altogether seven vehicles were measured, two two-axle Euro 3 -class vehicles as references, three new two-axle Euro 4 -class vehicles and two new three-axle vehicles. The measurements were carried out on a chassis dynamometer, using three cycles describing actual driving. In addition to fuel consumption, exhaust emissions were also recorded for these vehicles. The differences in fuel consumption and operating expenses were after all smaller than first anticipated. In the case of the Euro 3 -class reference vehicles, the difference between the two vehicles was as high as 7-10{\%}. For new two-axle vehicles the difference in fuel consumption, when simulating urban driving, is only 3-4{\%}. Due to different technical solutions, the results were anticipated to be greater. In suburban driving although, the difference is at its most 11{\%}. In the class of two-axle vehicles, lowest fuel consumption was measured for a SCR vehicle, whereas in the case of the two three-axle vehicles, EGR technology resulted in lowest fuel consumption. The measurements do not give an unambiguous answer to whether the EGR- or SCR-technology is preferable regarding fuel consumption. The contemplation is hindered by two factors. On one hand, the order of superiority depends on the driving cycle, on the other, the actual exhaust emissions do not match with expectations. The two EGR vehicles (same make) produced higher NOx -emissions than the manufacturer's Euro 3 -engine. The most fuel efficient SCR -engine is not truly Euro 4 -class what comes to NOx -emissions. Only two of the new vehicles, both with SCR technology, produce NOx -emissions genuinely matching their classes. Both fuel consumption and exhaust emissions have been observed in the study. In case exhaust emissions were completely disregarded, fleet decisions might be directed towards fuel efficient vehicles which after all do not reach the level of emission performance that reasonably could be expected.",
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Nylund, N-O, Erkkilä, K & Hartikka, T 2007, Fuel consumption and exhaust emissions of urban buses: Performance of the new diesel technology. VTT Tiedotteita - Meddelanden - Research Notes, no. 2373, VTT Technical Research Centre of Finland, Espoo.

Fuel consumption and exhaust emissions of urban buses : Performance of the new diesel technology. / Nylund, Nils-Olof; Erkkilä, Kimmo; Hartikka, Tuukka.

Espoo : VTT Technical Research Centre of Finland, 2007. 54 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2373).

Research output: Book/ReportReportProfessional

TY - BOOK

T1 - Fuel consumption and exhaust emissions of urban buses

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N2 - The research was carried out by the Finnish Public Transport Association. Altogether seven vehicles were measured, two two-axle Euro 3 -class vehicles as references, three new two-axle Euro 4 -class vehicles and two new three-axle vehicles. The measurements were carried out on a chassis dynamometer, using three cycles describing actual driving. In addition to fuel consumption, exhaust emissions were also recorded for these vehicles. The differences in fuel consumption and operating expenses were after all smaller than first anticipated. In the case of the Euro 3 -class reference vehicles, the difference between the two vehicles was as high as 7-10%. For new two-axle vehicles the difference in fuel consumption, when simulating urban driving, is only 3-4%. Due to different technical solutions, the results were anticipated to be greater. In suburban driving although, the difference is at its most 11%. In the class of two-axle vehicles, lowest fuel consumption was measured for a SCR vehicle, whereas in the case of the two three-axle vehicles, EGR technology resulted in lowest fuel consumption. The measurements do not give an unambiguous answer to whether the EGR- or SCR-technology is preferable regarding fuel consumption. The contemplation is hindered by two factors. On one hand, the order of superiority depends on the driving cycle, on the other, the actual exhaust emissions do not match with expectations. The two EGR vehicles (same make) produced higher NOx -emissions than the manufacturer's Euro 3 -engine. The most fuel efficient SCR -engine is not truly Euro 4 -class what comes to NOx -emissions. Only two of the new vehicles, both with SCR technology, produce NOx -emissions genuinely matching their classes. Both fuel consumption and exhaust emissions have been observed in the study. In case exhaust emissions were completely disregarded, fleet decisions might be directed towards fuel efficient vehicles which after all do not reach the level of emission performance that reasonably could be expected.

AB - The research was carried out by the Finnish Public Transport Association. Altogether seven vehicles were measured, two two-axle Euro 3 -class vehicles as references, three new two-axle Euro 4 -class vehicles and two new three-axle vehicles. The measurements were carried out on a chassis dynamometer, using three cycles describing actual driving. In addition to fuel consumption, exhaust emissions were also recorded for these vehicles. The differences in fuel consumption and operating expenses were after all smaller than first anticipated. In the case of the Euro 3 -class reference vehicles, the difference between the two vehicles was as high as 7-10%. For new two-axle vehicles the difference in fuel consumption, when simulating urban driving, is only 3-4%. Due to different technical solutions, the results were anticipated to be greater. In suburban driving although, the difference is at its most 11%. In the class of two-axle vehicles, lowest fuel consumption was measured for a SCR vehicle, whereas in the case of the two three-axle vehicles, EGR technology resulted in lowest fuel consumption. The measurements do not give an unambiguous answer to whether the EGR- or SCR-technology is preferable regarding fuel consumption. The contemplation is hindered by two factors. On one hand, the order of superiority depends on the driving cycle, on the other, the actual exhaust emissions do not match with expectations. The two EGR vehicles (same make) produced higher NOx -emissions than the manufacturer's Euro 3 -engine. The most fuel efficient SCR -engine is not truly Euro 4 -class what comes to NOx -emissions. Only two of the new vehicles, both with SCR technology, produce NOx -emissions genuinely matching their classes. Both fuel consumption and exhaust emissions have been observed in the study. In case exhaust emissions were completely disregarded, fleet decisions might be directed towards fuel efficient vehicles which after all do not reach the level of emission performance that reasonably could be expected.

KW - public transport

KW - urban transport

KW - vehicles

KW - buses

KW - diesel engines

KW - fuel consumption

KW - exhaust emissions

KW - performance

KW - measurements

KW - operating expences

M3 - Report

SN - 978-951-38-6922-9

T3 - VTT Tiedotteita - Research Notes

BT - Fuel consumption and exhaust emissions of urban buses

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Nylund N-O, Erkkilä K, Hartikka T. Fuel consumption and exhaust emissions of urban buses: Performance of the new diesel technology. Espoo: VTT Technical Research Centre of Finland, 2007. 54 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2373).