Unveiling energy transition strategy: A deep dive into China's ambitious renewable energy policy and its impact on carbon emission dynamics

Over the past 70 years, China has issued approximately 20,000 renewable energy (RE) policies. How to interpret China's ambitious RE strategy through these policy documents and assess its effectiveness has been a question of interest. Therefore, based on 15,603 Chinese RE policy documents from 1975 to 2022, this study employs text mining, Latent Dirichlet Allocation (LDA), Policy Modeling Consistency-Text Encoder (PMC-TE), and System- Generalized Method of Moments (SYS-GMM). It assesses the policy input intensity (PII) for different energy types, regions, and time periods, while also investigating the impact of PII about RE on carbon emissions. The study findings are as follows: (1)The PII is not uniform, with hydropower having the highest PII at 80,591, followed by solar (25,839) and biomass energy (18,903). The PII of wind (11,377) and geothermal energy (11,340) is similar, while hydrogen energy exhibits the weakest PII at 3488. (2)There are regional disparities in PII, with solar and wind energy being most prominent in northern regions, solar and hydropower being most significant in eastern regions, and wind and biomass energy aligning with local resources in southern regions. (3) RE policies have driven China's energy transition through four distinct phases. (4)Policy effectiveness varies, with solar, wind, and hydropower policies having the most significant impact on carbon emissions reduction, followed by biomass and geothermal energy. (5)China's government role in the RE strategy has shifted from a dominant role to a regulatory one.