Adjustable Sawdust Stove for Optimal Pot Placement and Improved Insulation Materials

Abstract

This study investigates the performance of a novel, single‐pot sawdust stove prototype designed for extended use applications requiring steady heat, such as daylong hot water provision, room heating, or bulk cooking for large gatherings. The prototype utilizes the rocket stove concept and prioritizes long burn times with minimal refuelling. The stove features a double‐walled, cylindrical combustion chamber made of mild steel (primary material) for efficient burning and heat retention. Fiberglass insulation (10 mm thick) is sandwiched between the walls to minimize heat transfer. An adjustable cooking platform, constructed with rods, pipes, and clamps, allows users to control the gap between the pot and the combustion chamber (currently set at 35 mm for a typical 200 mm diameter pot suitable for 3–5 people). This adjustability optimizes heat transfer for various pot sizes, improving overall cooking efficiency for a wider range of users. A heat spreader lid distributes heat evenly across the pot, while a sliding air inlet tray facilitates fire starting and airflow control. The combustion chamber dimensions (270 mm internal diameter and 420 mm height) are based on a prominent design by the Kisangani Smith Group’s Sawdust Stove Design of Tanzania Kisangani. The overall external stove diameter is 280 mm, with a mild steel outer wall (2.0 mm thick) surrounding the insulated combustion chamber. Controlled tests compared the prototype to a traditional charcoal stove. The prototype achieved significantly higher thermal efficiency (20.6% vs. 13%), faster rice cooking time (24.8 minutes vs. 31 minutes), and lower specific fuel consumption during cooking (0.55 vs. 0.62). This novel design, with its adjustable features and improved insulation, offers a more efficient, user‐friendly, and sustainable cooking solution for regions with limited access to conventional fuels and abundant sawdust. This research contributes to the development of efficient and sustainable biomass cookstoves, particularly in sawdust‐rich areas of Zambia.