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.