Electrochemical Conversion of Carbon Dioxide into Methane by Using Indigenous Microbes in Subsurface Oil Reservoir

ites of CCS. The long-term aim of this research is to establish a bio-technological system to convert geologically-stored CO2 into methane, as an energy resource. To develop a means for the conversion, we focus on technological application of a bio-electrochemical system using microbial catalyzed electrode (bio-cathode). On the surface of bio-cathode, methanogenic microorganisms utilize electrons to convert CO2 to methane (CO2 + 8H+ + 8e- → CH4 + 2H2O). We call it “electro-methanogenic” system. Such system is an attractive option for energy conversion, as the bio-cathode yields methane from electrical current, which can be provided by renewable energy sources. In other words, intermittent electrical energy provided by, for instance, wind turbines and solar cells can be stored in a stable energy form, methane.