Experimental and Numerical Assessment of a Sustainable Flat-Plate Solar Collector Using Recycled Polymer-Metal Composites in High-Altitude Andean Environments

Resumo

The thermal energy deficit in high-altitude rural regions necessitates cost-effective and sustainable technological solutions. While flat-plate collectors (FPCs) are mature technologies, their deployment in the Andean region is hindered by high material costs and extreme climatic variability. This study evaluates the thermal-hydraulic performance of a novel low-cost FPC engineered from recovered solid waste specifically, recycled 6063 aluminum frames and polyethylene terephthalate (PET) insulation. A coupled 3D Computational Fluid Dynamics (CFD) model was developed using the Discrete Ordinates (DO) radiation model to predict heat transfer phenomena under low-pressure conditions (3,000 m.a.s.l.). The numerical predictions were validated against experimental data obtained from a prototype installed in the Ecuadorian paramo. Results indicate a peak outlet temperature of 53.8°C under an irradiance of ~800 W/m², with the CFD model achieving a Pearson correlation coefficient of r > 0.95 and a mean relative error of 2.5% compared to in-situ measurements. These findings demonstrate that properly characterized recycled composites can achieve thermal efficiencies comparable to conventional materials, offering a viable pathway for circular economy implementation in renewable energy infrastructure.