The Role of Carbon Capture and Storage in Decarbonizing California’s Electricity Grid

Abstract

Affordable net-zero carbon electricity systems are critical in achieving a net-zero carbon economy, and California, who has long been a leader in climate policy, established a goal to reach a 100% clean grid by 2045. A capacity expansion and dispatch model is used to assess large-scale electricity power systems for California designed to meet policy standards while minimizing total system costs. The results of the analysis show that despite its comparatively high capital cost, including gas with carbon capture and storage (Gas-CCS) in the mix of electricity generation resources greatly reduces the cost of decarbonization for California as early as 2030 and in 2045. Without Gas-CCS, enormous capacities of solar and battery resources are needed in the future to reliably balance the load of the system throughout the entire year, which results in a highly overbuilt and expensive electricity system. Gas-CCS is able to generate electricity during the night-time and throughout times of the year when solar is not readily available, resulting in cost-effective decarbonization of the grid. In addition or as an alternative to Gas-CCS, we show that bioenergy with carbon capture and storage (BECCS) and direct air capture with sequestration (DAC), may also have important roles in play in decarbonizing California’s electricity sector. The scale of CCS development needed in California to cost-effectively meet its 2045 goals is technically feasible and California also has suitable storage sites for CO2. Implementation of CCS in California can be a robust strategy and effective tool for decarbonizing its electricity system and beyond.