Cost Modelling of Direct Air capture for Water-conscious Generation of Hydrogen and E-Methanol in arid regions

Abstract

The production of fuels from renewable energy sources and CO2 is a good way to move forward and mitigate climate change, reduce greenhouse gases and achieve a sustainable energy transition. This work presents a cost model for the production of e-methanol using hydrogen and CO2 with a target of 10,000 tonnes of e-methanol per year. The proposed model is an integrated system that includes a solid direct air capture system to produce carbon dioxide and water as feedstocks for the methanol reactor as well as a solid oxide electrolysis cell to produce hydrogen which is combined with CO2 in the reactor to produce e-methanol. The overall system is powered by a PV+batteries system. An economic analysis was conducted to determine the cost implications of the project, considering a 20-year lifetime and a 5% discount rate. Our analysis shows that variable operating costs represent 5050% of the total project costs over the life of the project, followed by capital expenditure 29 and fixed operating costs 2121%)). The levelized cost method was used to determine the price of the outputs. Therefore, the analysis showed a levelized cost of electricity LCOE of 0.11 €/kWh, while the levelized cost for carbon dioxide and water were 335.45 €/t and 238.70 €/t, respectively. Due to the immaturity of solid oxide electrolysis and the cost of electricity, which influences the cost of green hydrogen production, we have a levelized cost of hydrogen LCOH of 8459.918459.91€/t The production of e-methanol is mainly influenced by the cost of green hydrogen and carbon dioxide. The levelized cost of e-methanol is estimated at 2144.352144.35€/t. However, under current market conditions, our methanol is uncompetitive compared to the fossil-based methanol which is priced at 395 €/MT. A sensitivity analysis was conducted to assess the influence of some parameters such as the chemicals replacement, electricity and water on the cost. The results have shown that the cost of electricity and the maturity of technologies using innovative materials significantly affect the cost of green hydrogen and subsesubsequently the cost of e-methanol. Making e-methanol competitive and accessible at a lower price requires more research and development, policies and regulations to accelerate the energy transition to a world without greenhouse gas emissions.