• This report establishes an evaluation methodology that can be applied to Beijing’s Low Emission Zone (LEZ) and Congestion Charging (CC) policies, in order to quantify the air quality benefits of these two policies.
  • The air quality benefits are associated with stringent traffic restrictions. In the long term, both LEZ and CC can have significant emissions-reduction effects.
  • LEZ is better suited to control particulate matter (PM) and nitrogen oxides (NOx), whereas CC will perform better in reducing hydrocarbons (HC) and carbon monoxide (CO).
  • We suggest that municipal governments implement multiple measures to deal with vehicle emissions, and evaluate the benefits of different policy scenarios to determine the most effective way to reduce pollutants.
  • The LEZ/CC’s effect on air quality improvement can be highlighted in public communication strategies to increase public acceptance of the policies.

Background and Objectives

Beijing’s severe congestion and air quality issues require immediate government action on mitigation measures. Rapid urbanization and motorization pose severe risks to Beijing’s traffic flow and environmental quality. The Beijing Municipal Government has issued a series of transport demand management (TDM) measures and energy conservation and emissions-reduction policies in an effort to tackle environment problems. One of the main challenges for the government is to quantify the emissions-reduction effects of different policy schemes and compare the effectiveness of those schemes.

The purpose of our research is to provide technical support for Beijing and other Chinese cities regarding LEZ/CC policies to be adopted in the future. The report summarizes existing vehicle emission and fuel standards in Beijing and China and analyzes current vehicle emissions in Beijing. Based on a literature review of prevailing international vehicle emission models, we establish an evaluation methodology that can be applied to Beijing’s LEZ/ CC policies.

About This Report

This report has been prepared by Beijing Transport Institute and World Resources Institute. It is the second of a planned series of Beijing LEZ/CC project reports. The series aims to bring the successful international practices of LEZ/CC policies to China and make recommendations on how to implement these strategies in the Chinese context. The first published working paper in the series was Study on International Practices for Low Emission Zone and Congestion Charging1, which focused on the successful experiences of London, Singapore, and Stockholm with LEZ/CC policies. The analysis emphasized the preparation stage, scheme design, technology, public communication, implementation and management, and policy effects. It summarized the key factors leading to successful implementation and provided suggestions for implementation of LEZ/CC in China. The present report focuses on development of the evaluation methodology that can be applied to Beijing transport policies, especially LEZ/CC policies. Its purpose is to guide the government in quantifying the positive effects of policies on vehicle emissions reduction and comparing the effectiveness of different policies.

Research Methodology

This research establishes an evaluation methodology that can be applied to LEZ/ CC, to evaluate the emissions-reduction effects of both policies. The project develops a vehicle emissions accounting model to evaluate the emissions-reduction potential of transport policies. Using input data on traffic volume and speed provided by the Beijing Transport Institute, we design, collect, and analyze key model parameters that are sensitive to road traffic, vehicle structure, and speed. Through estimation of short- and long-term pollutant emissions of LEZ/CC scenarios and a control group, we test and evaluate emissions-reduction effects of LEZ/CC policies. To understand more deeply how the LEZ/CC policies help reduce vehicle emissions, this research uses a macroscopic emission accounting model to evaluate the overall emissions-reduction effects of LEZ/CC, and calculates the annual aggregate emissions of different policy scenarios in the base year and target years.

The project employs the mesoscopic static network evaluation model to evaluate the effects of LEZ/CC on reducing pollutant emissions in specific areas and key road sections on the basis of the Geographic Information System (GIS) platform.

Key Findings and Recommendations

The results show that in the long term both policies have good emissions-reduction effects. LEZ is better suited to control particulate matter (PM) and nitrogen oxides (NOx) whereas CC is more effective at reducing emissions of hydrocarbon (HC) and carbon monoxide (CO). If traffic restrictions tied to emission standards are more stringent (e.g., no vehicles below National Standard III are allowed to enter the 6th Ring Road area of Beijing), the LEZ policy would have greater emission-reduction effects.

Based on our research, we propose the following suggestions for decision-makers to promote LEZ/CC policies:

  • Apply the evaluation methodology for emissions reduction to different trans- port scenarios, so as to provide strong support for the decision-making process.
  • Implement multiple measures to comprehensively deal with vehicle emissions, especially for heavy polluting vehicles, to effectively reduce emissions of target pollutants.
  • Communicate the benefits of LEZ/CC policies on air quality improvement via public communication strategies, to increase public support for the policy.