Innovative Semiconductor-Based System for Converting Waste Heat from Industrial Gases into Electrical Energy

This study presents the design and implementation of an innovative, cost-effective, and high efficiency semiconductor-based system for converting waste heat from industrial gases especially methane into usable electrical energy. The proposed system achieves a conversion efficiency of 48%, an output voltage of 300 V DC, and a power capacity of 1.5 kW per unit. It integrates modified thermoelectric generators (TEGs) based on bismuth telluride-antimony telluride (Bi₂Te₃-Sb₂Te₃), custom-engineered MOSFET transistors (TIP41C) enhanced with a silicon nitride insulating layer, high-efficiency dual-transformer boost converters, and high-sensitivity methane sensors with a detection range of 0–2000 ppm. The system was developed through five iterative phases from July 2023 to January 2025, evolving from a 5 V prototype to a full-scale industrial model. Field experiments conducted in cement and petrochemical plants in Egypt and Saudi Arabia demonstrated 94% operational stability under harsh temperature ranges (200–600°C). Simulations using MATLAB/Simulink and COMSOL Multiphysics validated heat transfer, voltage dynamics, and gas response behavior. Results indicated a significant improvement in voltage output and efficiency compared to conventional TEG and organic Rankine cycle (ORC) systems. The system also demonstrated a CO₂ emission reduction of 0.18 kg/kWh, translating to 1.8 tons annually per unit, and aligns with SDGs 7, 9, and 13, as well as ISO 14001 standards. With a scalable manufacturing cost of $350 per unit in mass production, the projected social return on investment (SROI) is $5.2 per dollar over three years. Recommendations include scaling to other industries, integration with machine learning algorithms, and the use of enhanced thermoelectric materials such as PbTe to improve low-temperature effi iency.