Comparative techno-economic and life-cycle assessment of power-to-methanol synthesis pathways

Abstract

Abstract The deployment of “Power-to-Methanol” technologies by exploiting electrochemical reactions with CO2 as feedstock has received traction lately; primarily due to the continuous drop in renewable electricity price. Here, we compare techno-economic and climate benefits of three emerging “Power-to-Methanol” routes, including one-step CO2-to-methanol electrolysis; two-step synthesis, involving H2O electrolysis; and three-step synthesis, involving H2O electrolysis, and CO2-to-CO electrolysis. This study identifies key economic drivers and sets the technological goals for “Power-to-Methanol” routes to be competitive. We report that under current techno-economic conditions, none of these three emerging routes are compelling with levelized cost $860–$1585/ton methanol, which is ~2–4 times higher than the current market price ($300/ton–$500/ton). However, under future conditions (notably electricity price 130 mA/cm2 (CO2-to-CH3OH), >360 mA/cm2 (CO2-to-CO)), and energy efficiency >40%, which would make one- and three-step “Power-to-Methanol” routes economically and environmentally competitive over fossil-based process in future.