Three companies have announced that they have demonstrated further advancement of a new cutting-edge electrochemical technology that converts carbon dioxide in raw biogas to pipeline-quality renewable natural gas (RNG).
That is a critical improvement in the science of upgrading waste emissions to RNG, said Southern California Gas (SoCalGas), Pacific Gas & Electric, and Opus 12 in a joint statement.
The single-step process is designed to use renewable electricity and provide long-term storage of excess wind and solar power, Kallanish Energy reports.
The 12-month research and development project was funded by SoCalGas and PG&E and builds on the success of an initial feasibility study in 2018.
Raw biogas is produced by anaerobic breakdown of waste from dairy farms, landfills, and sewage. It contains 60% methane or natural gas and 40% carbon dioxide.
While current biogas upgrading technology removes the carbon dioxide from biogas, the new technology captures the carbon dioxide and converts it into additional renewable fuel.
Opus 12, a clean-energy startup with its origins at Stanford University and the Berkeley National Lab, has created a new proprietary Polymer Electrolyte Membrane electrolyzer that uses electricity to convert water and carbon dioxide into RNG in one step. The technology differs from those that use microorganisms.
The latest demonstration shows that improved catalyst activity could speed up reactions by a factor of 5 and nearly double conversion efficiency.
That makes the technology commercially viable with other new biogas upgrading methods, the companies said in a statement.
The core technology was scaled up and tested using commercially available electrolyzer hardware.
The next step will be to test this technology for longer periods of time at an existing biogas facility.
Such RNG plays a big role in California meeting clean-energy mandates in the future.