Characterization of Resin‐Infused Nonwoven Natural Fiber‐Reinforced Epoxy Composites for Renewable Energy Structural Applications: Comparative Experimental and Finite Element Analysis

ABSTRACT Natural resource‐based composites are biodegradable, eco‐friendly, and sustainable; however, variations in their properties and performance quality present significant challenges. This study presents the fabrication and performance evaluation of nonwoven natural fiber epoxy composites intended for structural applications in renewable energy systems. The objective is to assess the mechanical and thermal behavior of resin‐infused nonwoven coir, palm, and kenaf fiber laminates, produced via vacuum bagging infusion technique, as sustainable alternatives to synthetic composites. Mechanical characterization included tensile, flexural, impact, and hardness testing, while thermal behavior was evaluated through thermogravimetric analysis. Finite Element Analysis (FEA) was employed to predict stress distribution, and Analysis of Variance (ANOVA) was used to determine the statistical significance of material and treatment effects. All treated nonwoven composites exhibited enhanced performance compared to untreated counterparts. Treated palm fiber composites achieved the highest impact energy absorption (5.90 J), while treated kenaf composites recorded superior tensile strength (56.12 MPa), flexural strength (76.70 MPa), and hardness (114 HRB), showing improvements of 16.9%, 36%, and 12.5%, respectively over untreated counterparts. Thermal onset degradation for treated kenaf composites reached 342°C. ANOVA results confirmed that fiber type and treatment had statistically significant effects on mechanical performance ( p ≤ 0.05). FEA predictions closely matched experimental trends, validating model accuracy. These findings support the suitability of bio‐based composites for lightweight, high‐performance and thermally stable components in renewable energy infrastructure such as wind turbine blades and solar panel frames.