Biogas upgrading is a developing market in France that involves removing contaminants like hydrogen sulfide, carbon dioxide, and water from biogas in order to inject biomethane into natural gas grids. There are several technologies used for upgrading, including water scrubbing, chemical scrubbing, pressure swing adsorption, and membranes. Cryogenic upgrading is also emerging. Business plans and economic studies are required for biogas upgrading projects, as they show the costs and necessary biogas prices to make investments in upgrading profitable, especially for smaller capacity projects.