Bridging the gap between economic viability and operational security in power system decarbonization: A temporal optimization approach for multi-period dynamic generation technology investment considering long short-term uncertainties

The global decarbonization of power systems faces the critical challenge of balancing economic viability and operational security, constrained by renewable energy inherent intermittency and immature commercial deployment of energy storage (ES)/carbon capture and storage (CCS) technologies. Conventional expansion planning prioritizes cost-effective carbon reduction at the expense of operational security requirements and fails to account for short-term uncertainties induced by seasonal variable renewable energy, thereby overestimating renewable penetration. Focusing on China, this study investigates the interaction between operational simulation and investment planning under carbon neutrality targets, while delineating the impacts of two critical long-term uncertainties on low-carbon transition: energy policy and carbon neutrality timelines. A multi-period dynamic optimization model is developed, integrating investment planning with techno-economic simulation to identify decarbonization pathways, which adopts a method that chronologically arranges seasonal representative scenarios to capture the short-term uncertainties. Key analyses include renewable energy-ES-CCS deployment scale, rationality of mandatory ES deployment policies, and flexibility requirement quantification. Results reveal that systematically considering security-economic tradeoffs reduces required wind-PV penetration to 50.38 % by 2060, versus conventional projections exceeding 60 %, preventing deployment plans from becoming economically inefficient "paper targets". This work provides critical insights for developing pragmatic transition strategies that reconciles decarbonization ambitions with engineering and economic realities.