Implementation gap of China's environmental policies: logic behind the over-implementation of the coal to gas transition

China has implemented numerous energy-related policies to tackle environmental and energy challenges, but not all policies have yielded desired outcomes. While policy failure due to insufficient implementation is often highlighted, less attention has been given to the issue of over-implementation. In the last decade, China has experienced a process of power recentralization, which has brought about systemic changes in environmental policy implementation. Over-implementation has emerged as a prevalent phenomenon in environmental governance. The questions thus arise are: why does over-implementation happen? What are the consequences? This study examines the phenomenon of policy over-implementation within China's environmental governance system, using the coal-to-gas clean heating project as a case study. The findings reveal that China's recentralization efforts have addressed long-existing root problems in the environmental governance system. The strong environmental commitment from the central government, coupled with authoritarian pressure and positive incentives, has resulted in local implementers self-reinforcing for better career prospects, leading to over-implementation of policies. However, such authoritarian enforcement may overlook conflicts at the street bureaucratic level and opposition from those affected by the policies, potentially causing social injustice.