On-road performance and emission characteristics of CNG-gasoline bi-fuel taxis/private cars at the roadside environment

The real-world emission factors (EFs) and emission performance of bi-fuel (CNG/GAS) vehicles have been seriously investigated by the emission scientists and urban planners. In the present study, we propose an almost new practical methodology and perform on-road experiments on 60 bi-fuel vehicles to discuss the impacts of vehicle speed, fuel type, usage, and accumulated mileage on the CO, HC, and NOx EFs. 80% and 20% of the tested vehicles were private cars (PCs) and taxis (TXs), respectively. TXs and PCs are compared together based on their emission performances, emission characteristics, vehicular specific power (VSP) distributions, and type of fuel. The results show that in the entire cases except for GAS-PCs, CO EFs increased with vehicle speed. Although CNG vehicles show less HC EFs, they produce higher NOx mileage-based EFs compared to gasoline ones. NOx mileage-based EFs decrease with vehicle accumulated mileage, whereas the opposite trend was observed for the CO and HC EFs. Burning CNG rather than gasoline decreases 70% and 42% of CO, and 70% and 85% of HC mileage-based EFs in PCs and TXs, respectively. The influence of burning CNG on NOx emission of TXs seems to be insignificant, but NOx was more emitted by a factor of 1.7 in CNG PCs. Accumulated mileage has a destructive effect on combustion quality, especially in CNG vehicles. The factors of usage and accumulated mileage could considerably develop the VSP distribution and fuel consumption rate of GAS vehicles, while they have no detectable impact on that of CNG vehicles.


Adamović, Dragan, Dorić, Jovan, Miloradov, Mirjana Vojinović, Adamović, Savka, Pap, Sabolč, Radonić, Jelena, Turk Sekulić, Maja, 2018. 'The emission of BTEX compounds during movement of passenger car in accordance with the NEDC'. Sci. Total Environ. 639, 339–349.

Aslam, M.U., Masjuki, H.H., Kalam, M.A., Abdesselam, H., Mahlia, T.M.I., Amalina, M.A., 2006. 'An experimental investigation of CNG as an alternative fuel for a retrofitted gasoline vehicle'. Fuel 85, 717–724.

Banitalebi, Ehsan, Hosseini, Vahid, 2016. 'Development of hot exhaust emission factors for Iranian-made euro-2 certified light-duty vehicles'. Environmental Science & Technology 50, 279–284.

Carslaw, David C., Beevers, Sean D., Tate, James E., Westmoreland, Emily J., Williams, Martin L., 2011. 'Recent evidence concerning higher NOx emissions from passenger cars and light duty vehicles. Atmos. Environ. 45, 7053–7063.

Ghaffarpasand, Omid, Beddows, David C.S., Ropkins, Karl, Pope, Francis D., 2020a. 'Realworld assessment of vehicle air pollutant emissions subset by vehicle type, fuel and EURO class: new findings from the recent UK EDAR field campaigns, and implications for emissions restricted zones'. Sci. Total Environ. 734, 139416.

Ghaffarpasand, Omid, Reza Talaie, Mohammad, Ahmadikia, Hossein, Talaie Khozani, Amirreza, Davari Shalamzari, Maryam, 2020b. 'A high-resolution spatial and temporal on-road vehicle emission inventory in an Iranian metropolitan area, Isfahan, based on detailed hourly traffic data'. Atmospheric Pollution Research. https://doi. org/10.1016/j.apr.2020.06.006.

Grange, Stuart K., Farren, Naomi J., Vaughan, Adam R., Rose, Rebecca A., Carslaw, David C., 2019. 'Strong temperature dependence for light-duty diesel vehicle NOx emissions'. Environmental Science & Technology 53, 6587–6596.

Grange, Stuart K., Lewis, Alastair C., Moller, Sarah J., Carslaw, David C., 2017. 'Lower vehicular primary emissions of NO2 in Europe than assumed in policy projections'. Nat. Geosci. 10, 914–918.

Hickey, Neal, Boscarato, Ilan, Kaspar, Jan, 2014. 'Air pollution from mobile sources: formation and effects and abatement strategies'. Current Environmental Issues and Challenges. https://doi.org/10.1007/978-94-017-8777-2_2.

Huang, X., Wang, Y., Xing, Z., Du, K., 2016a. 'Emission factors of air pollutants from CNGgasoline bi-fuel vehicles: Part II. CO, HC and NOx'. Sci. Total Environ. 565, 698–705.

Huang, Xiaoyan, Wang, Yang, Xing, Zhenyu, Du, Ke, 2016b. 'Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part II. CO, HC and NOx'. Sci. Total Environ. 565, 698–705.

Huo, Hong, Yao, Zhiliang, Zhang, Yingzhi, Shen, Xianbao, Zhang, Qiang, Ding, Yan, He, Kebin, 2012. 'On-board measurements of emissions from light-duty gasoline vehicles in three mega-cities of China'. Atmos. Environ. 49, 371–377.

Jahirul, M.I., Masjuki, H.H., Saidur, R., Kalam, M.A., Jayed, M.H., Wazed, M.A., 2010. 'Comparative engine performance and emission analysis of CNG and gasoline in a retrofitted car engine'. Appl. Therm. Eng. 30, 2219–2226.

Jayaratne, E.R., Ristovski, Z.D., Meyer, N., Morawska, L., 2009. 'Particle and gaseous emissions from compressed natural gas and ultralow sulphur diesel-fuelled buses at four steady engine loads'. Sci. Total Environ. 407, 2845–2852.

Kwon, Sangil, Park, Yonghee, Park, Junhong, Kim, Jeongsoo, Choi, Kwang-Ho, Cha, JunSeok, 2017. 'Characteristics of on-road NOx emissions from Euro 6 light-duty diesel vehicles using a portable emissions measurement system'. Sci. Total Environ. 576, 70–77.

Lippmann, M., 1989. 'Health effects of ozone. A critical review'. JAPCA 39, 672–695. Mabahwi, Nurul Ashikin Bte, Hoon Leh, Oliver Ling, Omar, Dasimah, 2014. 'Human health and wellbeing: human health effect of air pollution'. Procedia - Social and Behavioral Sciences 153, 221–229.

Ntziachristos, Leonidas, Samaras, Zissis, 2000. 'Speed-dependent representative emission factors for catalyst passenger cars and influencing parameters'. Atmos. Environ. 34, 4611–4619.

Orun, A., Elizondo, D., Goodyer, E., Paluszczyszyn, D., 2018. 'Use of Bayesian inference method to model vehicular air pollution in local urban areas'. Transport. Res. Transport Environ. 63, 236–243.

Perugu, Harikishan, 2019. ‘Emission modelling of light-duty vehicles in India using the revamped VSP-based MOVES model: the case study of Hyderabad’. Transport. Res. Part D: Transport Environ. 68, 150–163. https://doi.org/10.1016/j.trd.2018.01.031.

Reşitoğlu, Aslan, İbrahim, Altinişik, Kemal, Ali, Keskin, 2015. 'The pollutant emissions from diesel-engine vehicles and exhaust aftertreatment systems'. Clean Technol. Environ. Policy 17, 15–27.

Shahbazi, Hossein, Taghvaee, Sina, Hosseini, Vahid, Afshin, Hossein, 2016. 'A GIS based emission inventory development for Tehran'. Urban Climate 17, 216–229.

Shi, Xueqing, Sun, Daniel, Fu, Song, Zhao, Zhonghua, Liu, Jinfang, 2019. 'Assessing onroad emission flow pattern under car-following induced turbulence using computational fluid dynamics (CFD) numerical simulation'. Sustainability 11, 6705.

Sun, Daniel, Elefteriadou, Lily, 2012. 'Lane-Changing behavior on urban streets: an “invehicle” field experiment-based study'. Comput. Aided Civ. Infrastruct. Eng. 27, 525–542.

Sun, Daniel, Zhang, Kaisheng, Shen, Suwan, 2018. 'Analyzing spatiotemporal traffic line source emissions based on massive didi online car-hailing service data'. Transport. Res. Transport Environ. 62, 699–714.

Sun, Daniel, Zhang, Ying, Xue, Rui, Zhang, Yi, 2017. 'Modeling carbon emissions from urban traffic system using mobile monitoring'. Sci. Total Environ. 599–600, 944–951.

Union, European, 2015. 'Emission Standards, Cars and Light Trucks'.

VijayaVenkataRaman, S., Iniyan, S., Goic, Ranko, 2012. 'A review of climate change, mitigation and adaptation'. Renew. Sustain. Energy Rev. 16, 878–897.

Wang, Fan, Li, Zhen, Zhang, Kaishan, Di, Baofeng, Hu, Baomei, 2016a. 'An overview of non-road equipment emissions in China'. Atmos. Environ. 132, 283–289.

Wang, Yang, Xing, Zhenyu, Xu, Hui, Du, Ke, 2016b. 'Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part I. Black carbon'. Sci. Total Environ. 572, 1161–1165.

Wang, Yang, Xing, Zhenyu, Zhao, Shuhui, Zheng, Mei, Mu, Chao, Du, Ke, 2016c. 'Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors'. Sci. Total Environ. 547, 422–428.

Xie, S., Hu, Jingnan, Bao, X., Li, Z., Wang, H., Zhang, K., 2011. 'Real-world emission characteristics of natural gas-gasoline bi-fuel vehicles'. Acta Sci. Circumstantiae 31, 2347–2353.

Yang, Wen, Yu, Chengyao, Wen, Yuan, Wu, Xinyi, Zhang, Wei, Wang, Xuejun, 2018. 'High-resolution vehicle emission inventory and emission control policy scenario analysis, a case in the Beijing-Tianjin-Hebei (BTH) region, China'. J. Clean. Prod. 203, 530–539.

Yao, Zhiliang, Cao, Xinyue, Shen, Xianbao, Zhang, Yingzhi, Wang, Xintong, He, Kebin, 2014. 'On-road emission characteristics of CNG-fueled bi-fuel taxis'. Atmos. Environ. 94, 198–204.

Yli-Tuomi, Tarja, Aarnio, Päivi, Pirjola, Liisa, Mäkelä, Timo, Hillamo, Risto, Jantunen, Matti, 2005. 'Emissions of fine particles, NOx, and CO from on-road vehicles in Finland'. Atmos. Environ. 39, 6696–6706.

Yu, Tai Yi, Chang, I. Cheng, Mei, Yin Hwa, Lu, Li Teh, 2012. 'Estimation of air pollutant emissions from mobile sources with three emission factors models'. Adv. Mater. Res. 550–553, 2378–2381.

Zhang, C.-H., Xie, Y.-L., Wang, F.-S., Ma, Z.-Y., Qi, D.-H., Qiu, Z.-W., 2011. 'Emission comparison of light-duty in-use flexible-fuel vehicles fuelled with gasoline and compressed natural gas based on the ECE 15 driving cycle'. Proc. Inst. Mech. Eng. - Part D J. Automob. Eng. 225, 90–98.

Zhang, Linling, Long, Ruyin, Chen, Hong, Geng, Jichao, 2019. 'A review of China's road traffic carbon emissions'. J. Clean. Prod. 207, 569–581.

Zhang, Qingyu, Fan, Juwang, Yang, Weidong, Fang, Ying, Bao, Zhen, Sheng, Yi, Cheng, Lin, Chen, Xuan, 2018. 'Influences of accumulated mileage and technological changes on emissions of regulated pollutants from gasoline passenger vehicles'. J. Environ. Sci. 71, 197–206.

Kaynak Göster

Atmospheric Pollution Research
  • ISSN: 1309-1042
  • Yayın Aralığı: Yılda 12 Sayı
  • Başlangıç: 2010


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On-road performance and emission characteristics of CNG-gasoline bi-fuel taxis/private cars at the roadside environment