China plays a crucial role in responding to global climate change. Provinces are the main sources of energy consumption and greenhouse gas emissions in China’s economic and social development. However, it remains unclear how local policies can be formulated and implemented to achieve carbon peaking and carbon neutrality in climate change mitigation. In this study, we take Zhejiang Province in China as the research object, based on the Low Emissions Analysis Platform (LEAP) to construct four social scenarios under different policies, comprehensively considering regional economic characteristics, population, and energy consumption patterns. The results show that to achieve Zhejiang Province’s goal of carbon peaking by 2030 while maintaining steady economic growth, additional measures are required to reduce energy consumption intensity or improve the power generation structure. Specifically, improving the power generation structure can lower the proportion of fossil energy consumption from 88.08% in 2020 to 73.72% in 2050. Otherwise, energy demand will increase to 228.06 million tonnes of coal equivalent and carbon emissions will be 487.76 million tonnes in 2050 in baseline. The economic viability of CCUS power generation is contingent upon the development of carbon taxes in the future. Once the growth rate of carbon tax reaches 7.2%, power cost will be 167.77 billion RMB and CCUS will become economically advantageous in 2050.