Thermodynamics, economic and carbon emission analysis of power-to-methanol process through alkaline electrolysis and monoethanolamine (MEA) carbon capture

•Complete simulation of renewable power to methanol production process;•Comprehensive analysis from energy, exergy, economy, and the environment perspectives;•Renewable power cost dominates the system's profitability;•Levelized cost of the renewable power to methanol is 840.50 $/ton.•Different CO2 calculation boundaries lead to opposite carbon emissions results; The integration of renewable power for hydrogen production, carbon capture, and methanol synthesis process presents a novel approach to produce green methanol and promote renewable energy utilization. There are few studies on full process modeling, and the impact of CO2 boundaries on carbon emissions and levelized costs has not been thoroughly analyzed. A complete modeling of the renewable power-to-methanol process was conducted in this work, considering energy, exergy, economy, and the environment perspectives. Thermodynamic and economic models were established, and a life cycle assessment model was conducted to evaluate the CO2 emissions. The renewable power-to-methanol process achieved energy and exergy efficiencies of 36% and 30%, respectively. The methanol levelized cost is 840.50 $/ton. The main factor affecting the levelized cost is the price of renewable energy. Different CO2 calculation boundaries lead to opposite carbon emissions results.