Power-to-methane: A state-of-the-art review

Power-to-Methane is a concept that converts electrical into chemical energy using CO2 and H2O. The concept brings the possibility of connecting the power grid to different sectors, where CH4 is needed such as mobility and industry. In this review, a comprehensive overview of the state-of-the-art of Power-to-Methane is presented. The Power-to-Methane process chain is described in detail. Fundamentals of water electrolysis are highlighted and cell technologies are discussed and assessed. CO2 sources are pointed out, CO2 separation technologies are depicted and compared, and some separation projects worldwide are listed. Thermodynamics of methanation process is analyzed; catalysts and reactors used are descripted and evaluated. Finally, Power-to-Methane plants in operation and construction are addressed.