Reducing operational costs of CO2 sequestration through geothermal energy integration

• For examined case studies, combined GCS-Geothermal is economically marginal.
• GCS-Geothermal direct use for desalination is the most attractive application.
• GCS co-located at a geothermal hot spot could make power generation feasible.

Commercial scale Geological Carbon Storage (GCS) projects have high capital costs and energy penalties that could be partially offset by including the production of geothermal energy. An important requirement is to match the geothermal resources available at GCS sites with local market opportunities. This paper examines the key parameters that determine viable economics for various hybrid GCS-Geothermal energy applications with a focus on Australian GCS flagship sites as case study examples linked with the initial observations from a pilot trial at the SECARB Cranfield CO2 demonstration project in Cranfield, Mississippi, USA. At first approximation, offshore GCS-Geothermal coupling seems unlikely due to well costs and the additional engineering requirements. The Perth Basin provides the best opportunity for GCS-Geothermal direct use for desalination. Whilst none of the case study examples would be ideally suited for GCS-Geothermal, insights gained are used to speculate on what conditions would be required for an economically viable opportunity. A strong enabling economic driver is when a GCS project already includes pressure relief water production as part of its base case.