Process development and techno-economic evaluation of methanol production by direct CO2 hydrogenation using solar-thermal energy

This study proposes and analyzes a novel methanol production process developed by integrating CO2 hydrogenation and thermochemical splitting technologies. Using Sunshine-to-Petrol, which produces liquid hydrocarbons using solar thermal energy, as the baseline framework, we developed a highly energy-efficient methanol production process comprised of the solar field for CO2 and H2O splitting using concentrated solar thermal energy, integrated with methanol production through the direct hydrogenation of CO2 and CO. The optimal process configuration and operating conditions for maximizing the amount of methanol were established using a sequential quadratic programming. Consequently, the proposed process achieved a high energy efficiency of 15.5%, and the minimum selling price of methanol was established as 0.94 $/kg, accompanied by a 26% improvement over previous schemes and other CO2-to-methanol frameworks. Furthermore, we examined additional alternative scenarios to establish the optimistic conditions such that the minimum selling price of 0.53 $/kg is considered as a competitive price in the methanol market.