Viessmann Group, BION® process
Viessmann Group and its former daughter MicrobEnergy GmbH (now part of the Hitachi Zosen Inova AG) have developed a process of biological methanation termed BION®. MicrobEnergy uses a non-patented mixed archaea culture. Nevertheless, this technology generates as well pure methane (purity >98%) under similar conditions, which can be injected directly into the gas grid, too. Since 2015, MicrobEnergy runs a demonstration plant in Allendorf, Germany. It was the first power-togas plant using biological methanation across Germany.