The provision and use of biomethane as a substitute for natural gas is considered to be a sustainable technology. But exactly how sustainable is it? How can sustainability be quantified at all? Life Cycle Assessment (LCA) is an internationally accepted tool for the provision of information about the environmental relevance of products and services. Biogasmax conducted LCA studies of biomethane from the participating plants across Europe. As the project results of BIOGASMAX show, biomethane offers great reduction potential compared to fossil fuels, since between 50 to 70 % less climate impact than natural gas over the entire life cycle. Since natural gas is considered rather clean compared to fossil fuels, biomethane comes out with even lower emissions against gasoline and diesel. The dedicated evaluation report contains the complete portfolio of impact categories.