Flexible CCS Technologies To Reduce the Cost of Net-Zero Carbon Electricity Systems

Abstract

Studies have shown that firm, low-carbon sources of power such as fossil-fueled power plants with carbon capture and storage (CCS) can reduce the cost of net-zero carbon electricity systems. But other developments on the path to decarbonization, particularly the proliferation of variable renewable energy (VRE) such as wind and solar, complicate the design of CCS-equipped plants, which must operate with reduced capacity factors and increased cycling. An increasing number of jurisdictions are committing to net-zero carbon electricity systems with high penetration of VRE. This paper considers the implications for CCS- equipped power plants via examination of grid capacity expansion and production cost modelling. The need to reconsider the optimal design and operations of CCS plants is presented, with focus on tradeoffs between capital cost, efficiency, and CO2 capture rate. Approaches to economic optimization via minimizing cost and maximizing operational profits are discussed. Finally, the case will be made that future CCS plants must either enable maximum power plant flexibility or change the operating paradigm so that plants can operate under more steady-state conditions and shift their electrical output to the grid via storage or provide another service such as removing CO2 from the air.