Electromethanogenic CO2 Conversion by Subsurface-reservoir Microorganisms

Abstract To develop a technological system to add substantial value to CCS operations, we are proposing a system to employ a new bio-electrochemical reaction, called “electromethanogenesis”, to convert geologically-stored CO2 into methane, a recycled energy source. In this study, we showed that microorganisms derived from a subsurface reservoir were electromethanogenically active. Moreover, the microbial consortium selectively enriched based on electrochemical activity had the highest electromethanogenic activity reported so far. Thus, our study indicated that, for the electromethanogenic conversion of geologically-stored CO2, recruitment of microorganisms endogenous to the reservoir was an effective strategy.