Experimental analysis of an enhanced biogas injera baking stove with an inverted conical combustion chamber

Traditional biomass-based injera baking stoves used in rural Ethiopia are characterized by low thermal efficiency, excessive fuel consumption, and significant greenhouse gas emissions, creating major environmental, health, and energy challenges. Despite the increasing interest in clean baking technologies, limited research has focused on optimizing biogas-powered injera baking systems while maintaining the traditional quality and cultural acceptability of injera. Therefore, this study aimed to develop and evaluate an optimized biogas-powered injera baking stove with improved thermal performance and reduced energy consumption.The study employed experimental and analytical methods to design and test an improved biogas stove incorporating an inverted 45° conical combustion chamber, enhanced insulation, and optimized air-fuel mixing mechanisms. Thermal efficiency, flame stability, heat distribution, energy consumption, and injera quality parameters were experimentally evaluated and compared with conventional biomass-based baking systems. The results revealed that the developed stove achieved a thermal efficiency of 36%, which is more than double that of traditional three-stone biomass stoves. The optimized system reduced energy consumption by approximately 40% per injera and demonstrated stable blue flame combustion with uniform heat distribution across the baking surface. Large-scale adoption by 5 million rural households could potentially save about 23,160 TJ (6.43 TWh) of energy annually. Furthermore, the produced injera maintained desirable traditional quality characteristics, including porosity, softness, flexibility, and uniform thickness, confirming the cultural acceptability of the technology. The findings indicate that the optimized biogas injera baking stove is an efficient, sustainable, and culturally appropriate clean baking solution for rural communities. Its large-scale implementation could contribute significantly to energy conservation, climate change mitigation, and improved household health conditions. However, long-term field-based evaluations are recommended to assess durability, operational stability, maintenance requirements, and environmental performance under diverse real-world conditions.