California utilities, Opus 12 advance technology that converts CO2 to renewable natural gas

Published on June 24, 2020 by Chris Galford

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Southern California Gas Co. (SoCalGas) and Pacific Gas and Electric Company (PG&E) have teamed up with clean energy startup Opus 12 to create an electrochemical technology able to turn carbon dioxide in raw biogas to renewable, pipeline-quality natural gas.

The companies announced further advancement in the effort this week, which they say will mark a critical improvement in evolving waste emissions to renewable gas. While the process has been ongoing for some time, the latest demonstration revealed that improved catalyst activity could hasten reactions by as much as five times, while nearly doubling conversion efficiency. That would officially make the technology commercially viable alongside other biogas upgrading methods.

“Our vision for deploying this technology in California is to recycle C02 emissions from industry and agriculture before they reach the air, and create valuable products such as renewable natural gas and feedstocks for everyday materials, chemicals, and even liquid fuels,” Dr. Etosha Cave, Opus 12 co-founder and chief science officer, said. “They are compatible with existing infrastructure, and when produced with renewable electricity, these products will have significantly lower lifecycle emissions than conventional products.”

The whole system consists of a single step, based on Opus 12’s Polymer Electrolyte Membrane electrolyzer, a technology that uses electricity to convert water and CO2 into renewable natural gas. Gases can be more easily stored for long periods with existing infrastructure, making the gains invaluable for those utilities interested in storing renewable electricity in battery systems.

“This cutting-edge method of using renewable electricity to convert carbon dioxide in biogas to renewable natural gas in a single-step process is significant to SoCalGas,” Yuri Freedman, SoCalGas’ senior director of business development, said. “As we work to meet California’s ambitious climate goals, emissions-reducing innovations like these will help us protect the environment by providing a reliable carbon-neutral fuel.”

Current biogas upgrading technology does exist, and it removes CO2 from biogas, but this new technology captures that CO2 and converts it for further use. A field demonstration is the next big goal, and the companies will move to test the technology for longer periods at an existing biogas facility.

“PG&E is deeply committed to meeting California’s bold vision for a sustainable energy future in a reliable and cost-effective manner for customers. We continue to work toward advancing innovation that provides new possibilities in our quest to reduce greenhouse gas emissions and find alternative sources of carbon-neutral fuel. We are very proud to be part of this collaboration with Opus 12 and SoCalGas,” said Francois Rongere, PG&E’s manager of Innovation and Research and Development.