Introduction to the thematic set: Geological storage of CO2, gas and energy

This thematic set emerged out of the 3rd EAGE Sustainable Earth Science Conference, held in the picturesque town of Celle in Lower Saxony, Germany, on 13 – 15 October 2015. This conference series was established to develop and promote an emerging group of applied geoscience topics focused on technologies for sustainable use of the subsurface to serve the energy transition; and the focus so far has been mainly on geothermal energy, CO2 storage and energy storage. Inspired by the research emerging from this conference, the conveners proposed a thematic set on the common ground between long-term geological storage of CO2 and the shorter-term cyclic storage of energy. The resulting set of papers is very rewarding, since they capture examples of all these topics and illustrate the complementary nature of subsurface studies on the storage of energy and CO2. We have arranged the set to start with two review papers, followed by three papers on energy storage and then a further three on CO2 storage.