Techno-economic analysis of solar-driven co-electrolysis for renewable methanol production using SOEC

The co-electrolysis of H₂O and CO₂ in a solid oxide electrolyzer cell (SOEC) integrated with solar energy leads to the development of renewable or near-zero emission technology for methanol production. Renewable methanol synthesis utilizing H₂O and CO₂ captured from different industrial processes has received much attention. In this paper, a high-temperature electrolyzer integrated with solar dish collectors and photovoltaic arrays is proposed and investigated for syngas production and methanol synthesis. Phase change material is used for long-duration thermal energy storage to make an uninterrupted operation. Thermo-economic and technical feasibility analysis of the proposed system is performed and the most influential operating parameters (direct normal irradiance, current density, SOEC operating temperature and pressure) are varied to evaluate the system's performance by parametric study. The hourly data for the year 2021 of the direct normal irradiance (W/m²), wind speed (m/s) and ambient temperature (°C) for the studied location in China is accessed and presented. The results of the study show that solar-to-fuel efficiency and methanol production rate are 29.27 %, and 41.85 kg/h, respectively, while the levelised cost of fuel (LCoF) is calculated at approximately 0.399 Euros/kg. The sensitivity analysis for the economic and thermodynamic structure is conducted and discussed.