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MPhil in Engineering for Sustainable Development

global challenges, engineering solutions

Trends in energy efficiency and CO2 emissions in China’s major cities:
An index decomposition analysis

WHB Chong

Trends in energy efficiency and CO2 emissions in China’s major cities:
An index decomposition analysis

The economy of China has been surging since 1980s. China is now the third largest economy in the world. Energy demand and carbon emissions in China have also increased rapidly. China has become the second largest energy consumer and the largest CO2 emitter in the world, in which energy use and carbon emissions from cities are the major sources. Statistical analysis is employed to analyze current information in terms of urban development, economic growth, industrial transformation and energy use in China’s 50 major cities. Six key cities include Beijing, Shanghai, Tianjin, Chongqing, Guangzhou and Hong Kong are selected for further analysis by using index decomposition method. This method exploits a factorization technique, which is widely used in energy and environmental analysis, to study the impact of changes in energy efficiency and carbon emissions.

Although the economic effect and energy intensity effect are the two dominant factors contributing to the increase and decrease in carbon emissions, this study reveals that there are variations in the ways driving forces contributed to carbon level in various cities. Therefore, a more contextualized, substantial and operable targets at local and regional level should be set by the local government. The central government should play as a coordinating role and make policy alternatives available to the local governments, so that the local governments can aptly select various options from a list of policy base on their specific conditions.

The decomposition approach can be a practical tool for the Chinese government to strengthen its energy efficiency monitoring system and quantify the progress for energy efficiency. Subject to availability of data, the monitoring system can be extended deeper and broader to all levels (national, regional, provincial and city) and sectors of its economy.


Course Overview


The need to engage in better problem definition through careful dialogue with all stakeholder groups and a proper recognition of context.


An ability to work with specialists from other disciplines and professional groups acknowledging that technical innovation and business skills also must be understood, nurtured and combined as precursors to the successful implementation of sustainable solutions.


An understanding of mechanisms for managing change in organisations so future engineers are equipped to play a leadership role.


An awareness of a range of assessment frameworks, sustainability metrics and methodologies such as Life Cycle Analysis, Systems Dynamics, Multi-Criteria Decision making and Impact Assessment.