Comprehensive performance analysis of a solar thermal/power assisted bromine-mediated propane dehydrogenation system: Energy, exergy, economic, and environmental perspectives

Conventional oxidative dehydrogenation of propane suffers from high energy consumption and substantial carbon emissions, limiting its sustainability. To address these challenges, this study proposes an innovative solar-assisted bromine-mediated propane dehydrogenation system that synergistically combines parabolic trough collectors (PTCs) and photovoltaics (PVs) for cascaded solar energy utilization. A comprehensive multi-criteria evaluation framework encompassing energy, exergy, economic, and environmental aspects is established, supported by detailed thermodynamic modeling via Aspen Plus simulations. Under design conditions (25°C, 1000 W/m2 solar irradiance), the system achieves an energy efficiency of 15.56% and an exergy efficiency of 27.36%, while reducing propylene production cost to $0.52/kg, a saving of $0.13/kg compared to conventional non-solar processes. Furthermore, the integrated solar design cuts energy consumption by 38.7% and achieves net-zero carbon emissions under peak irradiation. Off-design analysis indicates that increased irradiance reduces both operating costs and carbon footprint. Although enlarging the PTC/PV area requires higher initial investment, it offers significant long-term benefits. Sensitivity analysis identifies propane price and renewable electricity cost as the most influential economic factors. This work provides a foundational framework for solar-driven olefin production and demonstrates the potential of hybrid solar-chemical processes to simultaneously meet economic and environmental objectives.