Hydrogen to Methane—An Important Step in the Power-to-Gas Concept

The concept of Power-to-Gas (P2G) is regarded as a very promising alternative to store the excess of renewable electrical power as hydrogen and/or methane. The transformation of hydrogen into methane is made through CO2 methanation, which has the huge benefit of providing a way to valorize the excess CO2 generated typically by combustion of carbon-based fuels. The present article presents the state of the art in this area. It starts with the presentation of the P2G concept, emphasizing its potential for hydrogen storage as methane in the national grids, followed by a review of the used catalysts and their performances, ending with perspectives and conclusions.