Techno-economic analysis of large-scale production of e-methanol, via CO2- hydrogenation, in Power-to-X

Abstract: Global levels of carbon emissions are constantly rising causing irreversible damages to ecosystems. The heavy transport sector and the industrial sector are responsible for large amounts of the emissions on a yearly basis. Therefore, Power-to-X is presented as an alternative pathway for the production of industry standard chemical, in view of a green transition towards decarbonising emission-heavy sectors. Methanol is one of the desired end-products generated from a multitude of pathways within Power-to-X. Methanol, referred to as e-methanol if produced this way, are synthesised from hydrogen, produced by electrolysis powered from renewable sources, and captured carbon dioxide. Hence highlighting a green production of e- methanol. This project aims at evaluating different technologies in the production chain of e-methanol in order to do a techno-economic study of a plant configuration capable of producing 46,000 ton/year of e-methanol via green hydrogen and captured carbon dioxide. The technical evaluation showed that the best suited technologies for an e-methanol plant of this scale and configuration were hydrogen produced via a PEM electrolyser, compressed via mechanical multistage compressors, and distributed to a methanol synthesis plant together with carbon dioxide captured via amine-based absorption. A comprehensive simulation model of the methanol synthesis loop was developed with support of Aspen Plus, whilst the other process steps were estimated in a detailed economic analysis – with a basis in the capital- and operational cost associated with a large-scale commercialised e-methanol plant with an expected lifetime of 20 years of operation. The economic analysis showed that the levelized cost of methanol (LCoM) was 1041 €/ton, which is more than double the current market value price of methanol (400 €/ton). Additionally, the analysis showed that the net present value (NPV) of the e-methanol plant was negative 297 M€, if methanol was sold at the current market value, at the end of the project lifetime. The sensitivity analysis showed that electrical power consumption per produced kilogram of hydrogen and the current industrial price of electricity, had the largest effect on the NPV. However, a futuristic scenario was analysed where four parameters were changed based on forecasted values. This analysis showed that e-methanol production could become significantly profitable with a NPV of 111 M€ after the project lifetime. Hence justifying the growing interest of e-methanol production.