Trade policy uncertainty and improvement in energy efficiency: Empirical evidence from prefecture-level cities in China

In the face of the shocks from trade policy uncertainty (TPU), China needs to improve urban energy efficiency (EE) to achieve its "carbon neutrality" goals as scheduled, but the existing literature has no systematic research on this topic. This paper develops and estimates TPU and EE indexes by adopting the Bartik instrument's methods and dynamic slacks-based measure (DSBM). Furthermore, the authors conduct empirical tests on the influencing effect and transmission mechanism of falling TPU on urban EE after the US granted China permanent normal trade relations (PNTR) status in 2001 with a difference-in-difference (DID) model. The results of the empirical study show that urban EE improves by around 1.9% when TPU falls by 1%. A heterogeneity analysis also shows that a falling TPU has a more significant impact on EE in provincial capitals, open cities, "hygienic cities," highly marketized cities, and cities with a higher share of manufacturing. Falling TPU reduces the cost of foreign capital inflow into China. It drives progress in green technologies, thus improving urban EE by replacing energy factors with innovation-driven non-energy factors. Further, export expansion and export technology complexity significantly raise the stimulating impact of falling TPU on improvement in EE, but growing processing trade impedes this impact. The findings in this study offer a new perspective on estimating the effect of China's policies to respond to global climate change against the shock from TPU and provides new evidence for strengthening global energy cooperation.