Carbon dioxide electrolysis to ethylene – A techno-economic assessment for acidic-media systems

• Techno-economics of acidic-media CO 2 electrolysis to ethylene are explored. • Low voltages (<2.75 V) and high selectivities (>85 %) are key for feasibility. • Robust, low-cost, and stable catalysts/membranes will contribute to feasibility. • Feasibility requires lower electrolyzer costs and high ethylene production capacities. • Affordable electricity and CO 2 prices could enable compelling techno-economics. CO 2 electrolysis provides a sustainable route to the electrosynthesis of multi-carbon products, including ethylene. Recent progress in catalyst design and system integration has advanced the practicality of the CO 2 -to-ethylene process. This work provides the first comprehensive techno-economic analysis of ethylene electrosynthesis in acidic-media CO 2 electrolyzers, addressing key advantages such as high single-pass CO 2 conversion and the associated economic implications. More specifically, the study assesses the techno-economic impact of performance metrics, input parameters, and component/electrolyzer/system specifications and lifetimes, exploring the cost implications and importance of each parameter via a sensitivity analysis. The analysis identifies current density, cell voltage, ethylene Faradaic efficiency, electricity price, CO 2 price, electrolyzer cost, and system lifetime as the parameters to which the cost of ethylene electrosynthesis shows high sensitivity. The techno-economic assessment demonstrates that marketable ethylene electrosynthesis warrants improvements in the current density (>500 mA cm −2 ), cell voltage (<2.70 V), ethylene Faradaic efficiency (>75 %), along with a lower electricity price (<3 c kWh −1 ), a lower water price (<2 $ ton −1 ), a lower CO 2 price (<10 $ ton −1 ), a lower electrolyzer cost (<350 $ kW −1 ), and longer catalyst/membrane lifetimes (>8,760 h). The work concludes with scenarios that could render CO 2 -to-ethylene process techno-economically comparable with today’s carbon-intensive ethylene production processes.