Design Modification on Metallic Improved Cooking Stove KU-3 Model at Kathmandu University BijendraShrestha 1 ,Bim Prasad Shrestha 2 , Nawaraj Sanjel 3 and Malesh Shah 4 Department of Mechanical Engineering Kathmandu University Dhulikhel, Nepal Email: shrestha@ku.edu.np Abstract -Kathmandu University Department of Mechanical Engineering has collaborated with Alternate Energy Promotion Center/ Energy Sector Assistance Program for selecting appropriate model of metallic stove to be disseminated under subsidy program of Government of Nepal in high hill region of Nepal from the year 2007. After extensive test and verification KU-3 model was decided as the most appropriate model to be disseminated, and thus more than 5000 KU-3 model have already been installed in the last 3 years. ESAP has target to install additional number of 7000 of such units in other parts of country by March 2012. In this work, feedbacks from the users and site observations are used as basis for further modifications; the University is constantly moving ahead to come up with new version that could cater the current needs and demands as well. It has been found that the KU-3 model could be modified with following three options or their combination. 1. Based on economical consideration 2. Based on Water Sanitation and Hygiene ( WASH) 3. Based on multipurpose use. For Economic consideration, the double base plate in the combustion chamber has been replaced by one and size has been optimized, for WASH point of view, the WAPIC model used in Bangladesh as Chulli system, designed by Environment and Public Health organization has been integrated with KU-3 model to ascertain its effectiveness. For Multipurpose point of view, back boiler has been attached for hot water supply. In all above modification process, national testing protocol has been adopted for testing its efficiency such as WBT at Kathmandu University. For WASH consideration, the water before and after pasteurization has been tested at water laboratory. The preliminary result shows that there is great scope for further modification of KU-3 model to disseminate it in several high hill regions of Nepal. Keywords -KU-3, WASH, WAPIC, WBT, ESAP I. INTRODUCTION A. Background Nepal occupies 147,181 Sq. Km of area. Fuel wood production is 17,985,000 MT (Metric Tons). Each person/ family uses about 640/4000 kg of fuel wood per year. The demand of fuel wood is increasing while forest depletion is continuing very fast. The decrease in forestland is estimated to be 100,000 ha/year, while reforestation is estimated to be 15,000 ha/year only. Nepal’s per capita annual energy consumption, 14.06 GJ, is one of the lowest in the world. Only four other countries in the world have a per capita consumption lower than Nepal. 90% of Nepal's populations live in rural areas and the agricultural sector is the mainstay of rural population. The energy resources of Nepal consist of a combination of traditional and commercial sources of energy, including biomass, hydropower and alternative forms of energy. Petroleum fuel and coal are imported from other countries. Fuel wood accounts for 81% of the energy consumption and is mainly consumed in Rural Nepal. Two major characteristics of energy systems in Nepal are excessive dependence on biomass energy and very low efficiency in its use. Public, community and private forests are major sources of fuel wood. These sources are depleting rapidly as a result of exploitation and lack of adequate management. Other biomass resources– agriculture residue and animal waste– provide for 10% of the energy requirement whereas imported petroleum and coal provides 8%. Biomass available for energy purpose on a sustainable basis was estimated to about 23 million tons in 1991/1992, of which fuel wood based on accessible forests accounted for 33%, agricultural residue for 53% and animal dung for 14%. Fuel wood is used in traditional stoves of various kinds, or in improved and more efficient stoves for cooking and space heating. Cooking and heating are the main household energy needs. A variety of traditional cooking and heating stoves fired by biomass fuels is used in mountain households. In mountain areas, the demands of space heating are greater than the demands for cooking. In the mountain areas, 32% of the household energy is used for cooking and 56% for heating, compared with 40% for cooking and 36% for heating in hill areas. The remainder, 12% and 24% respectively, is used for lighting, electrical appliances, boiling water and agro-processing activities. Fig. 1 Biomass Energy Consumption in Nepal in 2006 A.D. (Source: Renewables and wastes in Nepal 2006)