Smart Design of a Composite-Enhanced Solar Drying System for Optimized Energy Utilization and Moisture Control in Agro-Products

Abstract

This study presents a performance evaluation of a solar cabinet dryer (SCD) enhanced with advanced composite materials to improve thermal efficiency and support sustainable drying applications. Conventional solar dryers are often limited by significant heat losses, uneven temperature distribution, and inadequate thermal storage. To address these challenges, the proposed SCD design incorporates carbon-fiber reinforced polymer (CFRP) panels for structural strength and durability, aerogel insulation for superior thermal resistance, and phase change materials (PCM) to enable effective thermal energy storage. These modifications aim to reduce energy losses and extend drying capabilities beyond peak sunshine hours. Experimental trials were conducted under controlled environmental conditions, with key performance indicators including drying rate, moisture removal efficiency, internal temperature consistency, and energy retention. The composite-based dryer demonstrated a 32% increase in drying efficiency and a 25% reduction in thermal energy losses compared to a traditional design. The results highlight the potential of using advanced composites to develop high-performance, eco-friendly solar drying systems suitable for agricultural and industrial uses, particularly in remote and off-grid regions.

Introduction

Drying is a crucial method for preserving agricultural products, and solar drying offers an eco-friendly, cost-effective alternative to traditional fossil fuel-based methods. Solar cabinet dryers (SCDs) are widely used for small to medium-scale drying but face issues like heat loss, poor insulation, uneven temperatures, and lack of thermal storage, limiting their efficiency especially in variable weather.

This study improves a conventional SCD by integrating advanced materials: carbon-fiber reinforced polymer (CFRP) for a strong, lightweight frame; aerogel insulation to minimize heat loss; and phase change materials (PCM) for thermal energy storage, allowing the dryer to maintain heat even during cloudy periods or after sunset.

Experimental comparison of the modified dryer with a conventional one showed that the new design maintained 5–8°C higher temperatures, increased thermal efficiency from 42% to 55%, and improved drying rates by about 30%. The PCM allowed the dryer to operate effectively up to 3 hours post-sunset without external energy. Although initial costs are higher, long-term benefits include reduced energy consumption, faster drying, higher throughput, decreased post-harvest losses, and a smaller environmental footprint by lowering reliance on fossil fuels.

The modified SCD thus represents a sustainable, efficient solution for agricultural drying, particularly suitable for regions with abundant solar energy and limited electricity access.

Conclusion

The integration of advanced composite materials, including carbon-fiber reinforced polymer (CFRP), aerogel insulation, and phase change materials (PCM), has demonstrated significant improvements in the performance of solar cabinet dryers (SCDs). These materials have proven to enhance thermal efficiency, reduce energy losses, and improve drying consistency. The use of CFRP provides structural integrity and reduces the weight of the dryer, while aerogel insulation minimizes heat dissipation, ensuring that more energy is retained within the drying chamber. PCM effectively stores excess heat during peak sun hours and releases it during non-sunny periods, extending the operational hours of the dryer and maintaining optimal drying conditions. The results of this study show that the modified SCD outperforms traditional models by improving drying efficiency, reducing energy consumption, and offering a more sustainable alternative for drying agricultural products. The potential for reduced post-harvest losses and the promotion of renewable energy use further align with global sustainability goals, particularly in rural and off-grid regions where access to electricity is limited. However, the initial costs of advanced composite materials remain a challenge. Further research focused on cost-reduction strategies for CFRP, aerogels, and PCM could pave the way for more affordable and widespread adoption of these enhanced solar dryers in developing countries. By making these advanced materials more cost-effective, solar dryers could become an even more viable solution for sustainable agricultural drying in regions with limited infrastructure and resources.

References

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Copyright

Copyright © 2025 Afjal Khan, Amit Shrivastava . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.