Baker Hughes Co. is expanding its global carbon capture portfolio with an investment in an upstart company developing synthetic natural gas (SNG) that could be stored and transported in existing pipelines.

The Houston-based oilfield services operator said Monday it is taking a 15% stake and a board seat in Germany’s Electrochaea GmbH. The Munich firm’s proprietary biomethanation technology manufactures SNG from green hydrogen and carbon dioxide (CO2). The SNG could be stored and transported in an existing gas grid.

Baker Hughes, which would draw on its broader carbon capture technologies, plans to work with Electrochaea to commercialize an integrated carbon capture and utilization (CCU) solution. The goal is to give customers the ability to transform CO2 emissions into...