Energy and exergy analysis of an integrated system with solar methane cracking and co-electrolysis of CO2/H2O for efficient carbon management

Abstract

In this paper, an integrated system is proposed for the production of turquoise hydrogen from methane cracking using solar energy. The produced hydrogen and carbon by-products are used in fuel cells to generate clean electricity. Syngas is produced through power generated via photovoltaics, using a solid oxide electrolyzer cell (SOEC). The SOEC co-electrolyzes the exhaust CO2 from the direct carbon fuel cell, along with H2O. The resulting syngas is subsequently converted into methanol. The system is modelled using Aspen Plus to obtain the thermodynamic evaluation. Mass, energy, entropy, and exergy balances are performed over the system's units. The energy and exergy efficiency of the subsystems is determined, with solar methane cracking system achieving energy and exergy efficiencies of 82.2% and 92.5%, respectively. The overall system produces methanol and generates 7.71 MW of electricity with the overall energy and exergy efficiencies of 40.6% and 37.5%, respectively.