Performance evaluation of improved biomass cookstoves used in Gambella refugee camps, Southwest Ethiopia

In Ethiopia, many rural households still depend on traditional three-stone open fires for cooking, leading to persistently high rates of biomass fuel use. To address this issue, considerable and sustained efforts have been made over decades to improve cookstove technology. Therefore, this study aimed to evaluate the performance of major biomass cookstoves used in Gambella refugee camps, using the Water Boiling Test (WBT) protocol at the laboratory level. Both widely used improved biomass cookstoves and the traditional three-stone stove were selected for the assessment. Thermal efficiency, specific fuel consumption, and time-to-boil were used as key performance indicators to compare each stove. The findings revealed that the three-stone open fire cookstove is the most commonly preferred cooking method among refugees. Alongside the traditional stove, the Clay (User Centered Design-UCD), Flexy, and Tikikil stoves were identified as the most frequently used improved biomass cookstoves. From the experimental test results, the specific fuel consumption of improved biomass cookstoves was recorded an average 140.53 g of fuel per liter, while traditional cookstoves consume an average of 214.8 g of fuel per liter of water. From this, it was estimated that the use of one improved cookstoves could save 72.93 g of fuel wood per liter of water than traditional cookstove. The thermal efficiency of improved biomass cookstoves had showed the highest value with an average of 31% while the three-stone stove had thermal efficiency of 13%. There was no significance difference in time to boil by which improved biomass cookstoves took an average of 19 min of cooking time per liter of water and open fire traditional stove takes an average of 18 min per liter of water. Therefore, it can be concluded that improved biomass cookstoves use less firewood, time and cost than traditional cookstove and this in turn reduces environmental impacts. Thus, relevant organizations should promote the distribution of improved biomass cookstoves for refugees to mitigate the harmful effects associated with traditional stoves. Future research should investigate the long-term health and well-being impacts of improved biomass cookstoves on refugees by comparative studies such as the Control Cooking Test and Kitchen Performance Test.