Spyridon Bellas is a Geologist (Patras University, Greece) and obtained his Ph.D. from the Freie Universtität Berlin, Germany. He is now the Principal Researcher at the Institute of GeoEnergy (IG) [former Institute of Petroleum Research (IPR)] of the Foundation for Research & Technology, Hellas (FORTH), based on the Technical University Campus of Chania, Crete Island, Greece. He was an External Evaluator of the Greek Authority for the Evaluation of the Quality of the Higher Educational Institutes (former H.Q.A., presently H.A.H.E., evaluating Departments and Universities of Greece) three times, and he won the “C. Ktenas” Prize for the Natural Sciences of the Greek Academy of Sciences. He is currently working on the Energy Transition subject from a Geoscientist's perspective, studying various aspects of geological storage for CCS and hydrogen, as well as the power generation applied in deep geothermal energy fields. Additionally, he geologically and geochemically investigates a) new sources of rocks and b) porous formations as potential reservoirs in the Mediterranean.