Combining CCS and Geothermal

One of the themes covered by GHGT-13 in Lausanne is the potential of combining CCS and geothermal energy. There are different ways in which geothermal energy might be used. One idea is to inject CO₂ into a saline aquifer at one point and then extract heat energy from another location within the same aquifer. Doublet extraction and injection of cooled water is a standard practice for delivering geothermal heat energy for district heating. The next step is to dispose of CO₂. The concept is still some distance from reality but initial research is underway. Another concept is the location of conventional fossil fuel power plant with a geothermal source. Here geothermal energy would be used to provide a heat source for the capture plant reducing the energy demand from the combustion of fossil fuels and improving the energy conversion efficiency of the power plant. Initial modelling suggests overall operational costs could be reduced leading to a lower levelised unit cost of electricity compared to a power plant with no additional contribution from geothermal energy.