Can e-CNY pilot policy promote green innovation? Empirical analysis based on data from Chinese cities

In the digital economy era, Central Bank Digital Currency (CBDC), as a new type of financial infrastructure, will also have an important impact on green development. In this paper, using the e-CNY pilot policy as a quasi-natural experiment, we explore the effect of e-CNY issuance on urban green innovation and its intrinsic mechanism by constructing a staggered difference-in-differences (DID) model. We found that the e-CNY pilot policy significantly increases the level of urban green innovation, and this effect gradually increases during the study period. The policy shows obvious regional heterogeneity, with more prominent policy effects in peripheral urban circles, central and eastern regions, resource-based areas, regions with high environmental attention, and regions with low digitalization levels. Mechanism analysis indicates that the e-CNY pilot policy enhances urban green innovation by improving digital financial level, optimizing resource allocation efficiency, and narrowing the digital divide. Further analysis reveals that green capital investment, the strength of intellectual property protection, and the level of green certification technology play significant moderating roles in this process. In addition, e-CNY pilot policy has a significant spatial spillover effect. Taking the e-CNY pilot policy as an entry point, this paper reveals the potential value and realization path of the CBDC in the field of green innovation. It provides both a theoretical basis for policy makers to enhance the e-CNY functional ecosystem and optimize pilot project designs, as well as practical guidance for accelerating China's green and low-carbon economic and social transformation amid the digital economy wave.