Development and Testing of the Berkeley Darfur Stove
Darfur, one of the poorest regions in Sudan, has been in the midst of a complicated and bloody conflict since 2003 that has resulted in the displacement of 2.2 million citizens. The displaced, known as Internally Displaced Persons (IDPs), are crowded into refugee camps scattered across the region with low fuelwood productivity and no alternative means of fuel. Unsustainable harvesting has led to increasing zones of total denudation around the camps, now extending several kilometers in all directions from the camp boundaries. Women who leave the camp to fetch fuelwood are subject to rape and mutilation due to the continuing conflict.In November of 2005, a team of scientists from LBNL visited Darfur to assess the potential of fuel-efficient stoves ("FES") as a means to mitigate the fuelwood shortage. In addition to conducting a systematic informal survey, the team found that a metal FES, known as the Tara, required 50% less fuelwood to cook an IDP meal than the inefficient three-stone-fire used by 90% of the IDPs. The LBNL team emerged from the triprecommending a metal FES based on the Tara, but with two specific design modifications to make it suitable for conditions in Darfur. These included improving the mechanical stability of the stove during vigorous stirring, and maintaining or improving performance during a breeze. In Spring 2006, an interdisciplinary team of four Berkeley students (3 graduate and 1 senior undergraduate) took on the project of designing, fabricating, and testing the recommended modifications as part of a UC-Berkeley course entitled Design forSustainable Communities. Under the guidance of Prof. Ashok Gadgil, the students designed several modifications to improve stove performance in windy weather, including a wind-shield around the upper stove body, and the addition of a metal ring to prevent direct air flow through the stove body. Stakes were also added to the stove body to improve stability during vigorous stirring. The students fabricated a prototype fortesting, known as the "Berkeley Darfur Stove," or BDS. Since no existing stove test was relevant to the conditions of Darfur, a new protocol, known as the Darfur Cooking Test (DCT), was developed by the students to compare the fuel efficiency of two stoves. This protocol is specific to the conditions in Darfur, incorporating both windy and non-windy conditions, along with the cooking pots, food preparation methods, and meals employed by IDPs. The complete DCT protocol is presented in Appendices 1 and 2. The BDS prototype was tested against the original Tara stove using the newly developed DCT along with a simple tipping test (to compare stability). Fuelwood usage by the BDS was found to be consistently less than that of the Tara stove under all tested conditions. Compared to the Tara, the BDS was found to save 56% (with wind) and 40% (without wind) of the fuelwood required to cook sauce-like mulah (one of two staple IDP foods)and to save 74% (with wind) and 8% (without wind) of the fuelwood required to cook the dough-like assida (the other staple food). Using these numbers, the BDS was found to have a net annual fuelwood savings of 72% over the three-stone-fire in Darfur. The 4 stability of the BDS during stirring was also found to be much better than the Tara, requiring > 117 N of lateral force to tip compared to just 22 N. Implications of full adoption of the BDS throughout Darfur include saving 370 million kg of fuelwood per year, along with a monetary savings of US $222 per family per year for IDPs who buy fuelwood or a savings of 18 hours of labor effort per week for IDPs who currently collect fuelwood. Annual avoided CO2 emissions would come to 6 million tonnes per year worth $12 million annually assuming the lowest market price of $3 per tonne1 of CO2. Most significantly, the risk of rape and mutilation for those who collect fuelwood would be reduced by three-quarters. Additional expected benefits include substantial reduction in the inhalation of harmful wood-smoke by IDP women and girls, and significant reduction in the risk of fire to the IDP shelters because the BDS fully encloses the open flames.