(554g) Early-Stage Evaluation Procedure for CO2 Utilization Technologies at Low Technology Readiness Levels: A Case Study for Electrochemical Production of Ethylene

CO₂ utilization (CU) has attracted much attention in both industry and academia due to its potential to mitigate greenhouse gas (GHG) emissions while generating economic benefits^1,2. Most emerging CO₂ utilization technologies still remain at low technology readiness levels (TRLs)³ except a few cases such as the production of commodities^4,5 and synthetic fuels^6,7. Given the large number of potential CU technologies, successful early-stage evaluation can identify promising ones to guide R&D investments. Thereby, overall cost can be reduced drastically since large-scale experiments and demonstration at higher TRLs are by far the highest cost components in process development can be prevented for non-promising technologies⁸. However, key challenges of early-stage evaluation are the limited availability and uncertainty of data⁹ that are addressed in this contribution.

We propose a systematic and comprehensive procedure for the early-stage evaluation of emerging CU technologies. More specifically, we employ the TRL scale and focus on TRL 2–4. The procedure consists of three steps: 1. data preparation, 2. data calculation, and 3. performance indicator calculation. The performance indicators are grouped into five categories: material, energy, GHG reduction, economics, and combined GHG reduction and economics. The procedure also depends on the type of CU technology, namely, thermochemical, electrochemical, and biological CO₂ conversion. We demonstrate the proposed procedure on co-electrolysis of CO₂ and H₂O for ethylene production^10,11, which is studied as if it were at TRL 2, 3, and 4. We conceptually design the ethylene production process (for the analysis at TRL 4). Then we calculate the performance indicators to discuss how the evaluation outcomes evolve with increasing TRL.

Reference

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