CO2-Plume Geothermal

CO2-plume geothermal is a technology that combines carbon capture and storage with geothermal energy extraction, using carbon dioxide itself as the underground heat-extraction fluid rather than water. In its closed-loop cycle, CO2 is injected into a naturally permeable deep reservoir, where it is heated by the surrounding rock; production wells then bring the heated supercritical CO2 back to the surface, where it passes through a turbine to generate electricity before being cooled, condensed and re-injected, keeping the carbon permanently sequestered underground. Although CO2 carries less heat capacity than water, its much lower viscosity lets it flow faster through a reservoir, and proponents report that a CO2-plume system can generate more than twice the power of a comparable conventional water-based geothermal system under similar conditions. The approach is pursued as a dual-purpose technology, storing greenhouse gas underground while generating renewable electricity from the heat that gas carries with it.