Power-to-methane technology is a promising solution to facilitate the use of excess variable
renewable energy for biomethane production. In this approach, hydrogen produced via
electrolysis is used to upgrade raw biogas, which can be subsequently used as fuel or
stored in the gas grid. Ex-situ biomethanation is an emerging technology that could
potentially replace conventional energy-intensive biogas upgrading methods and allow CO
2 utilization for biomethane production. This work provides a comprehensive overview on …