Techno-economic optimization of methanol production with hybrid solar technologies in Chile

Production of low-carbon methanol (MeOH) requires reliable, round-the-clock heat and power. This study develops an integrated techno-economic optimization framework for methanol production in Antofagasta, Chile. A renewable energy (RE) system comprising concentrating solar power (CSP) with thermal energy storage (TES), photovoltaics (PV), battery energy storage (BESS), and a molten-salt electric heater (EH) is coupled with parameterized black-box process models for desalination, electrolysis, methanol synthesis and distillation, and hydrogen (H 2 )/methanol buffers. Annual simulations at 5-minute resolution evaluate four configurations: PV and CSP–PV systems, each paired with either proton exchange membrane (PEM) or alkaline electrolysis (AEL). The optimization jointly sizes RE and H 2 –MeOH components to minimize the levelized cost of methanol (LCOM) subject to a 10% purchased-electricity constraint. Across 80,000 simulated designs, optimized LCOM values range from 0.99 to 1.18 €/kg. CSP–PV–AEL achieves the lowest LCOM at 0.99 €/kg, followed by PV–AEL at 1.03 €/kg, CSP–PV–PEM at 1.12 €/kg, and PV–PEM at 1.18 €/kg. Cost-optimal solutions purchase 3.31–8.79% of electricity from the grid. CSP–PV configurations benefit from TES-backed nighttime generation, direct process-heat supply, and conversion of excess PV electricity to stored heat through the EH, reducing curtailment and supporting higher process utilization. PV configurations remain competitive but require larger storage capacities. Overall, the results demonstrate the value of co-optimizing heat, power, storage, and the H 2 –MeOH process chain.