Experimental performance and economic analysis of a hybrid PVT system with H2O/CuO nanofluid and recycled waste materials

• A hybrid photovoltaic–thermal (PVT) system with nanofluid cooling is experimentally studied • Recycled metallic waste materials are used to enhance heat transfer and sustainability • Electrical energy output increased by up to 31.74% compared to a conventional PV system • Energy efficiency improved by up to 28.86% under real outdoor operating conditions • Techno-economic analysis confirms low LCOE and short payback periods for arid climates High operating temperatures in hot climates reduce photovoltaic (PV) performance by decreasing open-circuit voltage and electrical output. This study experimentally evaluates three modified photovoltaic/thermal (MPVT) configurations to enhance PV cooling and improve overall energy generation. A parallel-tube heat exchanger with horizontal manifolds is attached to the rear surface of a PV module. The first configuration uses an H₂O/CuO nanofluid as the coolant (MPVT@NC). In the second and third configurations, recycled stainless-steel filings (MPVT@NC-SF) and recycled aluminum filings (MPVT@NC-AF) are inserted between the tubes to improve thermal contact and promote heat transfer. This approach introduces a practical and low-cost route for waste material valorization while improving MPVT performance in sustainable building applications. Two identical systems are constructed and tested outdoors from 07:00 to 18:00 under the same operating conditions, and results are compared against a conventional PV module (MPVT). Average surface temperatures of MPVT@NC, MPVT@NC-SF, and MPVT@NC-AF is decreased by 10.06%, 18.43%, and 27.9%, respectively, relative to TPV. Correspondingly, electrical energy generation is increased by 12.44%, 23.14%, and 31.74% (baseline: 668 W). MPVT@NC-AF is produced by 17.16% and 6.98% that could provide more energy efficiency by improving of 10.08–28.86% across the modified designs, yielding an LCOE of $0.12–$0.16/kWh and payback periods of 2.11–2.96 years. The novelty of this study lies in integrating recycled waste metal filings into the PVT cooling structure to enhance thermal contact and simultaneously promote a circular-economy approach for building-integrated solar systems.