On geothermal and wind energy integrated methanol production by using green hydrogen

The main objective of this paper is to develop the geothermal and wind energy integrated methanol production system using green hydrogen through the hydrogenation of carbon dioxide captured directly from geothermal wells. In this regard, preliminary thermodynamic design and performance analysis were performed under various operational and environmental conditions. The integrated system consists of three subsystems which are i) a CO2 capture system integrated geothermal power plant (CGPP), ii) a wind energy-supported hydrogen production system (WHPS), and iii) a methanol production system (MPS). Consequently, the integrated system's highest energy and exergy efficiencies are found to be 54.84 % and 28.7 %, while the exergy efficiencies of MPS, WHPS, and CGPP were found to be 93.43 %, 16.32 %, and 59.04 %, respectively. Moreover, for 175 degrees C geothermal fluid temperature and 100 kg/s geothermal mass flow rate, the system has a potential of 5114 kW net electric generation and 19299 kW net useful heat production while it has along with the capability to produce approximately 597.6 kg/h of green methanol and 903.6 kg/h of oxygen for industrial usage. Through the implementation of this developed system, it has been estimated that approximately 25229 tons of CO2 emissions can be reduced annually.