Does New Infrastructure Affect Regional Carbon Intensity? Empirical Evidence from China

After the proposal of the carbon neutrality target, the reduction carbon emissions in China has become increasingly critical. The rapid advancement of new infrastructures, such as 5G infrastructure, artificial intelligence, and the industrial Internet, is a key factor influencing the change in carbon intensity through complex mechanisms, which necessitates a comprehensive understanding of their impact on regional carbon emission intensity. We employ the "structure-technology" effect as the transmission pathway and construct a model based on the STIRPAT model to compare and analyze the disparities in the influence of new infrastructures on the entire country and various regions. Moreover, spatial effects are also taken into consideration to investigate the pivotal areas for carbon emission reduction. The main results are as follows: (1) The carbon emission intensity in China demonstrates a consistent annual decline from 2011 to 2020. Regional disparities exist in both carbon emission intensity and the development of new infrastructure, with the western region exhibiting higher carbon emission intensity and lower investment in new infrastructure. (2) New infrastructure has the potential to positively impact the reduction of regional carbon intensity. However, the presence of an inverted U-shaped relationship suggests that China should avoid the indiscriminate expansion of new infrastructure. Instead, such projects can facilitate industrial structure optimization and technological advancements. (3) When considering regional nuances, the effect of industrial optimization is partially mediating in eastern and central China but obscuring in the western region. On the other hand, technological progress exhibits complete mediation in the central region. In conclusion, this study recommends specific measures for carbon emission reduction at both national and regional levels, accounting for the unique circumstances surrounding China's ongoing development of new infrastructure.