Can new energy demonstration cities break through the multiple carbon lock-in? Evidence based on double machine learning

Abstract

The “carbon lock-in (CLI)” dilemma poses a serious challenge for nations globally in pursuing sustainable development. The new energy demonstration city pilot policy (NEDCPP), as an important carrier for energy transformation, provides new momentum and direction for China to achieve “dual carbon” goals. The objective assessment of the carbon unlocking effect of this policy is of significant practical importance in achieving a harmonious progression between economic development and pollution reduction. This paper employs a double machine learning model to examine the influence of NEDCPP on urban CLI. The results show that: (1) The NEDCPP has markedly mitigated urban CLI, and this finding passes a series of robustness tests. (2) The causal mediation effect indicates that the NEDCPP suppresses the urban CLI through technological progress, institutional leadership, and social transformation. (3) It has a better CLI inhibitory effect on non-resource-based, small to medium-sized, key environmental protection, and new energy high-demand cities. (4) It breaks through the limitations of geography and administrative divisions, and plays a pivotal role in bridging the disparities in CLI across regions. This research offers empirical support for the global practice of NEDCPP, and expedite the response to global climate change.