Systemic Risks of Excessive CCS Deployment in Power-Sector Decarbonization

Carbon capture and storage (CCS) is widely acknowledged as a key strategy for deep decarbonization of the power sector. However, the systemic risks associated with excessive CCS deployment remain underexplored, particularly in fossil-dependent economies like China. Using a scenario-driven integrated framework coupling the Global Change Assessment Model (GCAM) with an input–output model, we quantitatively evaluate the implications of excessive CCS adoption in China’s power transition. Results indicate that excessive CCS deployment leads to a 14.63 petawatt-hour increase in thermal power generation by 2060, simultaneously causing a significant crowding-out of wind and solar capacity. This shift results in a 4,128 MtCO₂ emission rebound by 2060, exceeding 10 Gt by 2100─around 3% of the remaining carbon budget for the 1.5 °C target. Concurrently, air pollutant emissions, including CO, NO_x, and SO₂ rise substantially, with CO annual emissions projected to double post-2050. Additionally, the pathway is projected to reduce employment by an additional 11 million and take up nearly a quarter of China’s annual water use by 2060. Contrary to prevailing narratives emphasizing CCS cost-efficiency, this study highlights its structural trade-offs and underscores the need for system-wide optimization frameworks and adaptive governance mechanisms to ensure long-term sustainability.