Techno-economic and exergy analysis of e-methanol production under fixed operating conditions in Germany

Abstract

Electric-based methanol (e-MeOH) has the potential to substitute fossil-based hydrocarbons as the prominent feedstock in the production of climate-neutral synthetic fuels and organic chemicals because e-MeOH can be fully produced from renewable energy sources, such as solar photovoltaic (PV) and wind energy. It is basically produced via direct CO2-hydrogenation from captured CO2 and electrolytic H2. Although the techno-economics of the e-MeOH production process have been extensively studied, the published results have not included direct comparison of the reactor design configuration, different kinetic models, and exergy analysis.

To assess the process performance, the e-MeOH plant is modelled and simulated in Aspen Plus® on the basis of the state-of-the-art Lurgi MegaMethanol® technology. The in-house tool TEPET (Techno-Economic Process Evaluation Tool) assists with the techno-economic analysis, including a sensitivity analysis regarding CO2 and H2 costs and an exergy analysis of the e-MeOH plant.

With the recommended process configuration, the e-MeOH plant could achieve energetic and exergetic Power-to-Fuel (PtF) efficiency of 52.4% and 56.4%, respectively. The e-MeOH can be produced in 2018 at NPC 1129–1481 €/t or 57–74 €/GJ. These values would be doubled if the e-MeOH plant operates exclusively with the help of solar and wind energy in Germany. The study also investigates the impact of different published kinetic models of methanol synthesis, which alter the NPC by around 2.3%.