Renewable Syngas Generation via Low-Temperature Electrolysis: Opportunities and Challenges

Abstract

The production of syngas (i.e., a mixture of CO and H₂) via the electrochemical reduction of CO₂ and water can contribute to the green transition of various industrial sectors. Here we provide a joint academic-industrial perspective on the key technical and economical differences of the concurrent (i.e., CO and H₂ are generated in the same electrolyzer cell) and separated (i.e., CO and H₂ are electrogenerated in different electrolyzers) production of syngas. Using a combination of literature analysis, experimental data, and techno-economic analysis, we demonstrate that the production of synthesis gas is notably less expensive if we operate a CO₂ electrolyzer in a CO-selective mode and combine it with a separate PEM electrolyzer for H₂ generation. We also conclude that by the further decrease of the cost of renewable electricity and the increase of CO₂ emission taxes, such prepared renewable syngas will become cost competitive.