Using <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msub><mml:mtext>CO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>-Plume geothermal (CPG) energy technologies to support wind and solar power in renewable-heavy electricity systems

CO2-Plume Geothermal (CPG) technologies are geothermal power systems that use geologically stored CO2 as the subsurface heat extraction fluid to generate renewable energy. CPG can support variable wind and solar energy by providing dispatchable power, while Flexible (CPG-F) facilities provide storage, or both simultaneously. We present first study investigating how plants CPG-F may operate part of a renewable-heavy electricity system integrating plant-level plant models with systems-level optimization models. North Dakota, USA case demonstrate potential expand resource base locations not typically considered for power. find optimal capacity solar-wind-CPG model be up 20 times greater than peak-demand. reduce this modeled just over 2 peak demand storage seasonal short-term timescales. The operational flexibility is further leveraged bypass ambient air temperature constraint storing at critical temperatures. Across all scenarios, tax on emissions, order hundreds dollars per tonne, required financially justify using natural-gas plants. Our findings suggest play valuable role in future systems, we propose few recommendations its integration potential.