Evaluating Eco-Efficiency as a metric for sustainable urban Growth: A comparative study of provincial capital cities in China

•China’s urbanization has had a detrimental impact on the environment and increased resource, energy, and material consumption.•Urban sustainable development is an issue that is often debated in China due to all of these aspects.•Integrating environmental responsibility, green technology, green finance, and clean energy to advance sustainability goals effectively. China’s rapid urbanization has significantly impacted the environment, escalating resource, energy, and material consumption. Sustainable urban development has become a critical issue, with eco-efficiency emerging as a key metric for its assessment. This study employs eco-efficiency analysis, incorporating environmental contamination as an undesirable output, using data envelopment analysis (DEA) and a modified super-efficiency model for ranking cities. Empirical research was conducted on 30 Chinese provincial capital cities using real-world data. Results reveal that while many cities are eco-efficient, inefficiency is concentrated in underdeveloped regions of the southwest and northwest. Conversely, some eco-efficient cities exhibit high levels of pollution and intensive resource use, including land, energy, and water. The modified ranking methodology identified Yinchuan, Lanzhou, and Guiyang as the least eco-efficient cities, while Haikou, Fuzhou, and Beijing ranked as the top performers. The study highlights the need to reform the GDP-oriented development model and evaluation systems, continually upgrade industrial structures, and prevent the migration of heavy industries from more developed to less developed regions. These findings provide actionable insights for policymakers to balance urban growth with environmental sustainability.