Kampala, Uganda
A team of researchers from the Department of Mechanical Engineering at Makerere University has developed an innovative cookstove design that could significantly reduce household cooking costs, improve energy efficiency, and turn charcoal waste into a valuable source of clean cooking energy for Ugandan communities.
The groundbreaking study, titled “Towards Fluidization in Domestic Heat Systems: A CFD Analysis of a Fluidized Bed Cookstove,” was conducted by Nicholas Lwasa, Ronald Kayiwa, and Dr. Vianney Andrew Yiga and recently published in the international journal Multiscale and Multidisciplinary Modeling, Experiments and Design.
The research introduces a novel fluidized bed cookstove designed to burn charcoal dust directly without requiring briquetting. Charcoal dust is a common by-product generated during charcoal transportation, storage, and retailing, yet much of it is discarded despite having considerable energy value. The researchers sought to address this challenge by adapting fluidized bed combustion technology, traditionally used in industrial processes, for domestic cooking applications.
Turning Waste into Opportunity
In Uganda, biomass fuels remain the dominant source of cooking energy for households, institutions, and small businesses. However, conventional charcoal stoves are unable to efficiently utilize fine fuels such as charcoal dust because the compact particles restrict airflow and result in incomplete combustion. This limitation has left a potentially valuable energy resource underutilized.
The Makerere research demonstrates that fluidized bed technology can overcome this challenge by suspending sand particles with controlled airflow, creating intense mixing between fuel and air. This process promotes more complete combustion and efficient heat transfer, enabling charcoal dust to be used effectively as a cooking fuel.
Potential Benefits for Ugandan Households
The innovation has the potential to deliver substantial social and economic benefits across Uganda.
By enabling households to use charcoal dust that is often discarded or sold at very low prices, the technology could reduce household expenditure on cooking fuel while increasing access to affordable energy. The research also points to improved combustion performance, which can contribute to cleaner cooking environments and reduced exposure to harmful smoke emissions associated with inefficient biomass burning.
The technology could also support environmental sustainability efforts by reducing charcoal waste and maximizing the energy extracted from existing biomass resources. With pressure on Uganda’s forest resources continuing to grow, innovations that improve fuel efficiency and reduce waste can contribute to broader efforts to promote sustainable energy use.
Advancing Local Innovation
Using advanced Computational Fluid Dynamics (CFD) modelling, the researchers designed and simulated the performance of the cookstove before physical construction. The model predicted successful fluidization, stable operation, efficient fuel-air mixing, and combustion temperatures of approximately 726°C, demonstrating the feasibility of the concept.
The cookstove was designed with a firepower of 1.57 kW and a compact combustion chamber specifically optimized for household cooking applications. The findings suggest that fluidized bed combustion can be adapted from industrial systems to meet domestic energy needs in developing countries.
Beyond its technical contribution, the research highlights the role of locally driven innovation in addressing Uganda’s energy challenges. The study demonstrates how engineering research conducted at Makerere University can generate practical solutions with the potential to improve livelihoods, create new business opportunities, and support the country’s transition toward cleaner and more sustainable cooking technologies.
Looking Ahead
While the results are promising, the researchers emphasize that the next step will involve constructing and testing a physical prototype to validate the simulation results under real cooking conditions. Future studies will focus on evaluating the stove’s thermal efficiency, emissions performance, user experience, and long-term durability.
As Uganda continues to seek affordable and sustainable energy solutions, innovations such as the fluidized bed cookstove demonstrate the transformative potential of research and innovation in addressing everyday community challenges while advancing national development goals.
Authors: Nicholas Lwasa, Ronald Kayiwa, and Dr. Vianney Andrew Yiga, Department of Mechanical Engineering, Makerere University.
Publication attached below