Efficient Low-Grade Waste Heat Recovery from Concentrated Photovoltaic Cells Through a Thermolytic Pressure Retarded Osmosis Heat Engine

Triggered by the pressing need to enhance the power conversion efficiency of photovoltaic systems, this work introduces a novel hybrid system that combines a concentrated photovoltaic cell (CPV) with a thermolytic pressure retarded osmosis heat engine (PRO). This innovative integration allows for the efficient recovery and conversion of waste heat from CPV into additional electricity, addressing the challenge of high-output dependence on lower operating temperatures. A detailed theoretical model of the system is developed to ultimately derive and analyze the mathematical expressions for key performance indicators. Numerical analysis confirms that the novel system achieves a maximum power density, energy efficiency, and exergy efficiency of 239.28 W m-2, 13.9%, and 14.6%, respectively, which are improved by 13.06% over a sole concentrated photovoltaic cell. Comprehensive sensitivity analysis is conducted to obtain optimal selection criteria for crucial parameters including inlet concentration, concentration ratio, operating temperature, and diode ideality factor, which have a significant impact on overall performance. Comparative analysis shows that the CPV-PRO system outperforms existing CPV hybrids in terms of lower operational temperatures and enhanced economic viability, making it a superior choice for sustainable energy production.