Economic Parity Analysis of Green Methanol Synthesis Using Water Electrolysis Based on Renewable Energy

In this work, a techno-economic analysis combining process simulation and economic analysis was conducted for a methanol production capacity of 100 metric tons day–1. In particular, different water electrolysis types such as alkaline water electrolysis (AWE), polymer electrolyte/proton exchange membrane water electrolysis (PWE), and solid oxide high-temperature electrolysis (SOE) were considered as green hydrogen production methods for green methanol production. With the validated process model, the reaction temperature and pressure of 483.5 K and 63.03 bar, respectively, were selected as the optimized operating conditions based on reactant flow rates for a MeOH production capacity of 100 metric tons day–1 and energy efficiency. Based on the process simulation results, an economic parity analysis was conducted to find the switching point, which is the time that unit green methanol production cost is equal or less than gray one, by 2050. From the economic parity analysis, the unit MeOH production costs were $0.794–1.146, $0.897–0.958, and $0.697–1.177 kg–1 for green methanol production using AWE, PWE, and SOE, respectively, with solar photovoltaic-based renewable electricity. Moreover, MeOH parity can occur in 2044 for green methanol production using SOE. Therefore, it can be concluded that the possibility of green MeOH production can be confirmed in terms of the economic point of view and the continuous technology development of water electrolysis and low levelized cost of electricity can be necessary for green methanol production to put methanol parity forward.