Synergistic integration of SOFC in geothermal solar hybrid cycles: Energy, exergy, and economic perspectives

This study proposes and evaluates an upgraded hybrid geothermal–solar multigeneration power cycle incorporating an organic Rankine cycle (ORC), steam Rankine cycle (SRC), absorption chiller, and solid oxide fuel cell (SOFC) in a cascaded thermal recovery framework. The novelty of the proposed configuration lies in the simultaneous integration of geothermal and solar heat sources with multi-stage power and cooling production to enhance overall system efficiency. A comprehensive energy, exergy, and exergo-economic analysis is conducted to assess system performance and to benchmark the upgraded configuration against a base cycle. The results indicate that the proposed system delivers a net electric power output of 307.62 kW, with overall energy and exergy efficiencies of 24.84% and 18.18%, respectively. Compared to the base cycle, energy efficiency is improved by 2.76%, while exergy efficiency increases by 8.12%. The total operating and maintenance cost rate of the system is estimated at 22.61 $/h. In addition, a parametric analysis is performed to investigate the effects of key thermodynamic parameters on power output, efficiencies, and cost rate, providing useful insights for optimal design and operation of hybrid renewable multigeneration systems.