| Title | The Value of Bulk Energy Storage in Sedimentary Basin Geothermal Resources for Reducing CO2 Emissions |
|---|---|
| Authors | Jonathan D. OGLAND-HAND, Jeffrey M. BIELICKI, Thomas A. BUSCHECK |
| Year | 2016 |
| Conference | Stanford Geothermal Workshop |
| Keywords | sedimentary basin, carbon-dioxide, bulk energy storage, water-energy nexus, renewable energy |
| Abstract | We present an approach that estimates the value that bulk energy storage (BES) in sedimentary basin geothermal resources could have for reducing carbon dioxide (CO2) emissions from regional electricity systems. BES can be used to time-shift electricity that is generated from wind and solar resources in excess of demand to times when that electricity is needed. BES can indirectly reduce CO2 emissions if this time-shifted electricity displaces generation from power plants that emit CO2 (e.g., coal, natural gas). If CO2 is used as the medium for energy storage, where excess electricity is used to compress and inject CO2 into sedimentary basins, this CO2-BES approach can directly reduce CO2 emissions if the CO2 has been captured from power plants. This stored, pressurized, and geothermally-heated CO2 can be produced to the surface, where the energy is converted to electricity in a CO2-Geothermal power plant. As such, CO2-BES can directly reduce CO2 emissions by sequestering them in the subsurface and indirectly reduce CO2 emissions by displacing electricity that is generated from fossil fuels with time-shifted electricity that was generated by renewable energy technologies. We developed an optimization approach to estimate the indirect CO2 emission reductions that can occur by using CO2-BES for various prices on CO2. The direct CO2 emission reductions are calculated using CO2-BES operational parameters. Our results indicate that the direct value to CO2 is more than twice the indirect value to CO2. Thus, this study suggests that BES in sedimentary basin geothermal resources is a far more effective approach to reducing CO2 emissions from the electricity system than conventional BES approaches. This work was funded by the U.S. National Science Foundation Sustainable Energy Pathways program, grant 1230691. |