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Removing Smoke from Nepali Kitchens by Kayeswar Man Sulpya
[top] [end]Stove for cooking injeraThe main objectives of stove programmes in Nepal are to develop and disseminate improved cookstoves that reduce both fuel consumption and the level of noxious gases that contaminate households. Smoke is a major problem for women and their families. Studies and test results show that respiratory illnesses are the major contributor to infant mortality in Nepal. So far, more than 60,000 ICS have been disseminated, but the exact number in use is unknown.At the beginning of the project, a study was undertaken to determine what type of stove was used and what extension strategy was necessary for dissemination. Traditionally women cook on semienclosed chulos or on open fires' The size of the kitchen, its position in the house, the ventilation area, and the number of fireplaces and kitchens in a particular household vary widely throughout the country. In some areas the fire is also used to provide heat and light. Among some ethnic groups the cooking is a religious ritual. [top] [end]Carbon monoxide emissionsTo test the levels of noxious smoke given off by different cooking systems, carbon monoxide measurements were taken with open fires, semi-enclosed chulo, and improved cookstoves with chimneys, by using a portable carbon monoxide analyzer (capable of reading to an accuracy of 0.01% CO). Room volume, areas of windows and doors, and dimensions of the ICSs and other stoves were recorded. The test results listed in Table I show that carbon monoxide emissions are significantly lower for a properly installed ICS compared to either the traditional stove or the medium or badly installed ICS. It is also apparent that there is a much lower variance in the emissions from the well installed ICS. This indicates clearly that a well-installed ICS coupled with a chimney can reduce smoke in the kitchen.[top] [end]Chimney construction and installation problemsChimneys built from blocks of mud formed in wooden moulds are made in Nepal villages. During transportation to the project areas many chimneys are cracked and broken. Most stove organizations face problems with chimney installation. The project has to pay for the construction and installation. In poor houses with thatched roofs and wooden wails, chimney installation is very difficult and extra care should be taken. Chimneys less than four to five feet high cause low draughts, and the second cooking pot does not get enough heat this is one of the reasons people abandon ICS. Most of the houses in Nepals hills and mountains are made from stone. Knocking out a hole in the wall for the chimney outlet is difficult and time consuming. Lack of confidence and limited skill; restrict women's involvement in chimney construction. The study found that most chimneys are incorrectly installed at a right angle to the wall, causing another draught problem. Some installers found making a hole in a slanting position for the chimney outlet difficult when there are big stones in the wall. Upper floor chimneys are even more difficult to install securely. Table 1: Average carbon monoxide emissions from different stoves
[top] [end]MaintenanceChimney maintenance is a real problem. In Nepal, people, particularly those from higher castes, have assumed that it is the installers job to clean and maintain the stoves. Where there are no cleaners, chimney and stove maintenance and performance is low. Sometimes, bad installation, neglect of the stove, or failure to clean the chimney results in sparks leaving the chimney and igniting the roof thatch.[top] [end]EffectivenessAlthough most stove organisations in Nepal favour chimney stoves because they are effective in removing smoke but these stoves do not necessarily save fuel. Incorrectly designed chimneys, or failure to use dampers cause excessive fuel consumption or poor combustion.Construction of inefficient 'look-a-like' copies of ICS with chinmeys was observed in Surkhet district. The installers and the organizations were unaware of the critical technical parameters that must be observed. Evaluation shows that these stoves consume more fuel that traditional stoves. However, well-designed, well-installed and well maintained chimney stoves do perform better, and do save fuelwood. Studies proved that fuel efficiency was 21 to 25 per cent. Inadequate training, bad installation and poor maintenance are the major causes of the failure of past cookstove programmes in Nepal. [top] [end]Chimney CostsBetween 1984 and 1985, RECAST started to commercialize pottery stoves in Kathmandu. Stove. together with chimneys were marketed and about thirty were sold. Shop-keepers then refused to sell the stove because of the need to stock so many parts keep the parts outside the shop, and to show buyers how to put together all the chimney parts. If one piece is broken, there is a delay until the potters car deliver again. In addition, the cost of a chimney is double the cost of a stove. This affects the 'payback period and the stoves affordability. Metal chimneys cost more than twice the price of the stove and are too expensive for the rural Nepali as well as being difficult to use.Mud blocks, produced by family members with wooden mould can be used successfully to build chimneys (see figure 2). Mud-brick chimneys in exposed positions can be damaged by rain and may allow water to leak into the stove. To tackle this a few organizations have built chimney caps to give protection from wind and rain (see figure 3). In the Kathmandu valley stoves are installed on the top floors of houses, with a special smoke removal hole in the roof about 1.5 feet in diameter, and a rain protection cover. In urban and semiurban areas, a chimney hood is used for smoke removal. [top] [end]ICS promotionThe ICS being introduced in Nepal is a chimney stove. During the winter however, most people use both a traditional open fire and an ICS for heating. The open fire is used for cooking animal feed and so the stove chimney only removes about 30 per cent of the total smoke produced.Work in Nepal will continue with the introduction of portable, improved stoves installed in well ventilated kitchens and with smoke removal hoods and chimneys such as those being developed by ITDG in Kenya or with 'cooking windows' (hoods and chimneys built into the walls) now being demonstrated by the Hanoi Architect Institute in Vietnam (see page 22). For more details of the ICS programme see GLOW, Vol 11, March 1 994. [top] [end]Contents: Boiling Point 34: Smoke Removal
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Page created:
21 August 2007; Last edited:
01 December 2008; Version: 1 | ||||||||||||||||||||||
Pagename: RemovingSmokeFromNepaliKitchens @HEDON: | ||||||||||||||||||||||
