On-road remote sensing of CO and CO2 of motor vehicle exhaust emissions in Beijing using a TDLAS system

On-road motor vehicle emissions have been estimated being the single largest contributor of major atmospheric pollutants worldwide. The amount of motor vehicles in Beijing has rapidly grown in the past few years and will increase even more noticeably in the near future. It is therefore clearly required that a targeted approach to identifying the grossly polluting vehicles will have maximum impact on reducing the detrimental effects of the emissions. In this paper we will introduce an on-road motor vehicle exhaust emission monitor built by our group. This monitor was fabricated with tunable diode laser absorption spectroscopy (TDLAS) technique. On-road remote sensing of CO and CO2 of the motor vehicle exhaust emissions on Xueyuan road and at Dayangfang motorway toll station in Beijing were performed with this monitor. Analysis of the results shows that only 73.4% on-road motor vehicles are clean. Among the rest more than 15% are heavy gross polluters, which should be warn for repair or removed from service.