Carbon dioxide (CO2) capture and geologic storage (CCS) can be utilized to generate geothermal power highly efficiently and to provide grid-scale subsurface energy storage - if desired simultaneously. As a result, the CCS facility turns into a simultaneous CO2 capture, utilization and storage (CCUS) system. The base system is a so-called CO2-Plume Geothermal (CPG) power plant, where captured CO2 is circulated underground in saline formations or oil/gas reservoirs (e.g. during enhanced oil or gas recovery). In these reservoirs, the CO2 is geothermally heated, produced to the surface, expanded in a turbine to generate electricity, cooled, compressed, and then combined with any CO2 stream, from a CO2 emitter, before it is reinjected into the subsurface reservoir. The reinjection results in the continued growth of the subsurface CO2 plume and ensures that 100% of the subsurface-injected CO2 is eventually stored underground permanently. For subsurface (solar/wind) energy storage, the CPG CO2 cycle is separated into two operations (energy discharge and energy storage) by temporarily storing the CO2 in a shallow (~1 km deep) reservoir or in a gasometer during the energy discharge mode. For energy storage, the CO2 is released from the shallow reservoir or the gasometer and is reinjected into the deep (~2.5 km deep), and thus warm, “geothermal” reservoir. This type of subsurface (solar/wind) energy storage in the deep/warm reservoir is highly efficient and is massive (in the several GWh range). The subsurface-CO2-based energy storage system with a gasometer can be configured so that a heat sink (cold source) results, enabling district cooling. All of the above can in principle be combined with blue hydrogen facilities.