Near-future perspective of CO2 aquifer storage in Japan: Site selection and capacity

Japan has started a 5-year national R&D project titled ‘Underground Storage of Carbon Dioxide’ to reduce CO2 emissions into the atmosphere. One of the targets of the project is to select a few preferred storage sites as candidates for large-scale demonstration tests in the next phase, and for commercial use in the near future. For this purpose, we have ranked the sites in terms of capacity potential and CO2 supply potential, both of which significantly affect the storage economics. Here, the supply potential for a storage site is characterized by the annual amount of the stationary emission sources and the site–source distance; that is, how much CO2 is available and how far away it is. In total, 69 sites on land and offshore and 113 fossil fuel fired power plants are being considered. Finally, using the data on capacities and supply potentials, the sites are graded into three ranks. As a result, a map that shows the rankings of each site has been made. The sites in rank 1 are recommended as near-future candidate sites. These sites have a comparatively large capacity and can obtain a reasonable amount of CO2 from nearby sources without requiring a main pipeline.