Study on the energy efficiency improvement effect of dual-pilot financial policy under carbon emission constraints: based on the perspective of linkage between sci-tech finance and green finance

Urban energy efficiency (UEE) is essential for promoting sustainability under carbon neutrality goals, with financial policies serving as a key driver. While prior studies have examined the impacts of individual financial policies on UEE, the combined influence and synergies of multiple financial policies, particularly sci-tech finance and green finance policies, remain unexplored. This paper utilizes a dataset of 252 cities in China covering 2003–2019 and applies the double/debiased machine learning (DDML) model to examine the effect of the dual-pilot financial policy (DFP) on UEE. The DFP comprises the Promoting Science, Technology, and Finance Integration (PSTFI) pilot and the Carbon Emissions Trading (CET) pilot. The findings show that DFP significantly improves UEE by spurring technological innovation and alleviating factor market distortions. The impact is more pronounced in cities with stronger governmental environmental attention and financial regulatory intensity. Synergistic effects are observed between the PSTFI and CET pilots, with the dual-pilot policy outperforming either policy alone. Moreover, DFP mitigates the energy rebound effect, contributing to genuine energy savings. The above findings offer empirical evidence for enhancing the coordinated design of financial policies to advance urban low-carbon development and energy transition.