Cover Image
close this bookBoiling Point No. 38 : Household Energy in High Cold Regions (ITDG - ITDG, 1997, 40 p.)
View the document(introduction...)
Open this folder and view contentsTheme articles
Open this folder and view contentsGTZ News: Non-theme articles
Open this folder and view contentsReviews
Open this folder and view contentsNews


How do you define an efficient stove? For most people living in the South, it would be one which cooked food using a minimum amount of fuel in a reasonable amount of time. To achieve this, all the heat produced must be directed at the cooking pots and as little as possible lost to the surroundings. However, for those people living in cold, high regions, the stove may also be needed for heating the home. In these circumstances, heat lost to the surroundings is no longer regarded as waste heat. Any improved stove which is introduced in these regions must still provide space heating. Until recently, governments, programme planners, and researchers have failed to take this into account.

Many cold, high regions are desperately short of woodfuel for burning. Three-stone fires bum fuel inefficiently, providing less heat than a well-designed stove and producing large amounts of smoke. Because windows allow heat to escape, the rooms in these regions often have very little ventilation and the smoke cannot escape. This edition of Boiling Point looks at ways in which different areas have approached the problem of providing stoves which reduce wood consumption and smoke emission whilst providing space heating as well as heat for cooking

Boiling Point is a technical journal for those working with stoves and household energy.

It deals with technical, social, financial and environmental issues and aims to improve the quality of life for poor communities living in the developing world

Map showing high cold regions

(Source Solar Heating in Cold Regions published by IT Publications)

Your new editor - Elizabeth Bates

Elizabeth has now taken over the editorial chair from me and is in full control of Boiling Point. She has a husband who works in industry, a daughter at university and two sons at school. In 1972 she gained a degree in mechanical engineering and in 1979 she received a doctorate in materials science from Liverpool University. Since then she has done much voluntary work for IT Rugby on our technical library systems and working as a freelance editor for IT Publications.

Although BP's basic role of 'helping stove workers' will remain unchanged, she will, no doubt, be providing new ideas and making changes to produce an even more informative and attractive journal. With your help, she hopes to establish the same friendly relationship with our many unpaid authors, old and new, throughout the seventy countries where BP circulates.

To make stove and household energy programmes more effective, we must also help to enlighten and encourage aid and funding organizations and individuals who are interested in the health and quality of life of women and their families who live close to or below the poverty level. We also work to help programmes to minimize the problems of atmospheric pollution which damages family health and contributes to global atmospheric degradation. Stoves and fuels are at the heart of the problem and will remain BP's main concern.

Please help Elizabeth by sending her your comments, suggestions, criticisms and articles or news. We look forward to Elizabeth being involved with BP for several years and I wish her success and enjoyment in the task.

Ian Grant

In reply....

Editing Boiling Point is an exciting and challenging task. I am very grateful for all Ian's help in the transition period and look forward to receiving articles and letters from anyone who is willing to put pen or keyboard to paper. I do not have Ian’s many years of experience so will be very grateful for any criticisms or arguments with any of the articles published in BP; so if you disagree with anything, please write and say so and I will publish your opinions. I look forward to a very lively letters section!

Ian said that I might have some ideas on which way BP would evolve. It is too early to be specific but to me a perfect article should:

· say something which you feel may be useful to others working in household energy

· have lots of good pictures or photos; some of the best pictures in BP are line drawings sent by the authors. We rarely publish articles without some sort of illustrations

· explain ideas and details (such as abbreviations) which may be obvious to the writer, but will not be to the reader

Even if you have never written an article before, do not be put off as the information is the important thing and it's good to give me some editing to do, so keep the articles coming!

Household energy in high regions

Based on conclusions reached in the regional workshop on space heating in Pokhara, Nepal, February 1996

Energies domestiques dans zones de haute altitude:

L'auteur souligne que l'analyse des besoins de chauffage des locaux dans les rons de haute moutagnes requiert des approches spfiques. Les foyers multi-usages (cuisson et chauffage) sont encore peu rndus quoique les technologies sont disponibles. Gralement, les programmes sur les foyers n'accordent que peu de place a conception d'ipements multi-usages. Le moyen le plus simple de chauffer des locaux est d'utiliser la chemincomme radiateur. Cependant l'optimisation des deux fonctions implique davantage d'efforts en mati recherches dloppement. Quant au chauffage solaire des locaux, les couts restent extremement v Dans quelques zones montagneuses du Nl, ITDG a introduit des ipements de cuisson utilisant l'ctricitLes recherches qui ont ete men pour accroitre l'efficacite cuisson n'ont pas retenu l'attention des usagers dans la mre o pertes de chaleur servaient en fait au chauffage des locaux. Cet exemple montre que les strates de promotion des foyers sages multiples sont diffntes de celles ayant pour seul objet la diffusion de foyers utilisprincipalement pour la cuisson.

Cold altitudes and the need for space heating

A large majority of people in the developing countries live in hot climates and there is a need for coolness rather than heating in their homes. Nevenheless, there are many millions, particularly in the Himalayas or Andes, for whom heating is essential for survival, or is needed for a tolerable existence.

Mountain people have been largely overlooked in the design of household energy programmes and stoves and, as a result, space heating has never figured prominently in studies of energy policy.

Where stoves provide a heating function, they are often in rooms which are badly ventilated, in order to prevent heat loss. The resulting exposure to severe indoor air pollution is known to be bad for the health of both the stove users and other family members. Although the use of chimneys can help in reducing many of the harmful components in the room, they are not a cure for smoke problems. Fires may bum faster due to the improved draught, heat will be lost through them and fuel will be wasted.

Biomass use in mountain areas

As in almost all developing countries, biomass is the main source of energy for cooking and space heating and it is expected to remain so for the foreseeable future. The reasons are:

· A reliable supply of biomass is usually locally available.
· It is almost always the cheapest available fuel if the fuel has to be bought.
· Use of biomass is traditional and women are skilled in fuel
· Stoves have been designed or adapted to the local biomass fuels.
· There may be no other fuels available.

Meeting household energy needs

Stoves with several uses

Some combined cooking and space heating stoves have been developed with the aim of saving fuel, reducing environmental impact and yielding a range of benefits to users, particularly savings in time, work and money. Besides being able to afford an improved stove, the need for information about its good and bad points needs to be given to the user. If users do not know about the benefits and problems associated with a new stove they will often stay with the traditional stove.

Typical stove used in high regions for cooking and space heating

Cookstoves often have several functions; cooking, space heating, lighting, crop and fuel drying. social gathering etc. To succeed. stove development needs to take account of the local conditions, including house and stove construction materials and skills and the effects of weather. Social and cooking habits, affordability, complexity of the stove and ease of maintenance and repair need to be carefully checked. The materials used for stove construction should be obtained locally in view of the extreme difficulty of transportation. Stoves need to suit the available fuels, pot sizes and use (cooking on high heat, simmering, baking, special food preparations etc.).

The need to design stoves which perform several functions is often overlooked by stove programmes. In mountain areas, space heating is an important energy need which merits far more emphasis in energy policy and research.

The most straightforward way to provide space heating from a stove is to use the chimney as a heat radiator. This means routing the chimney through the room/s so as to transfer the heat from the exhaust gases to the air around the chimney. In many places, considerable local expertise on chimneys is available and can be used at the design stage.

The Chinese under-floor heating system, the 'Kang-Lianzao' bed stove (BP.29, page 33), may be appropriate for cold mountain regions elsewhere.

Solar energy for space heating

Active solar systems collect energy from the sun and then move the energy to storage or directly to the user by means of a transfer medium such as water. They perform well for domestic water supply but offer little for space heating. Adoption rates are very low due to the initial cost for the householder.

Passive solar designs have produced promising results in demonstration projects all over the world, notably on the high plains of Bolivia at an altitude of over 4000 metres. Similar work has been carried out by the LeDeG organisation in Ladakh. Passive solar design employs the principles of positioning buildings to achieve maximum winter insolation (incoming energy from the sun) whilst minimising heat losses. Window design has also been developed to a fine an. The trombe wall, which acts as a heat store during the day and gives out heat to the dwelling during the evening, is a simple device which also shows impressive results.

However promising the technical performance of these systems appears, the obstacles to the spread of solar designs are formidable. In particular, finding ways of influencing the design of new dwellings is a real barrier to the technology. The challenge of changing existing houses to adopt elements of solar design may be too great. In general, the costs of incorporating solar design into dwellings will restrict their spread beyond any but the most wealthy communities or for communal buildings.

Stove programmes

Stove programmes are often driven by the supply of the technology itself. Too frequently, they take a narrow view of stove development without considering other options which could achieve the same goals, such as better maintenance of traditional stoves or improving house construction.

Kang-Lianzao bed stove

During research into improved electric stoves for rural areas of Nepal carried out over the last six years, ITDG worked in several Himalayan communities. The electric stove incorporated a heat store made from stones. During one phase of the work, the local team tried to improve the insulation to this heat store, thereby saving most of the heat generated for cooking. They soon learned that the space heating characteristic of the new stove design was valued much more highly by users than the project team had initially imagined.

It is rare to find credit facilities and training programmes provided to local entrepreneurs and manufacturers in mountain communities. Availability of local materials for constructing space heating stoves is very limited and the import or transport of these materials increases the cost of stove manufacture.

Stove promotion

Strategies for promoting heating stoves have to be different from those used for cooking stoves because of the varying seasonal and local requirements for heating energy.

· A stove programme must be integrated with related programmes such as housing improvement, health and sanitation or rehabilitation work following disasters.

· It should be used to promote traditional skills and technologies and use local institutions.

· improved stove dissemination should lit in with the financial reality of households rather than the economic aims of governments.

· Technology research and development for solar systems should concentrate on cost reduction, for example, simple approaches using locally available building materials may be suitable for reducing the heat loss from the building.

Overall, a far greater understanding of the priorities of mountain communities is required. Lessons from the commercial spread of stoves in many countries have shown that successful stoves arc those which meet the expectations of their purchasers rather than the ambitions of their designers. A simple point, but fundamental to bringing mountain communities more directly into work on household energy.

Dissemination of improved stoves in Nepal

B B Gurung, CARE International in Nepal

Diffusion de foyers amor au Nl

Les foyers amores ont introduits au Nl par le Drtement de l'Agriculture dles ann 1950. Depuis la fin des ann1980, Care International a lanca promotion de foyers amoires en partant d'une approche into communautbficiaires sont oitement associ. Un certain nombre de les peuvent e dg: Les programmes doivent e lsur plusieurs ann, les villageois acceptent plus facilement les id nouvelles lorsqu'elles sont propag par des voisins. Afin d'accroe l'impact des foyers amor il est fortement recommend'associer les bficiaires lors des luations

Nepal is a small landlocked country situated between India and China. The population is over 21 million, of whom 90 per cent live in rural areas. There are no significant fossil fuel resources in Nepal and all petroleum products have to be imported from abroad. Rural people are fully dependent on fuelwood for energy. Studies show that the average fuelwood consumption per capita is very large (708 kg/year). The diminishing forest area has alarmed policy makers and planners into taking some immediate measures to reduce the fuelwood consumption. Greater environmental awareness is also a major factor in Nepal.

Introduction of improved stoves

Options and measures to optimize the use of fuelwood were explored. The introduction of Improved Cook Stoves (ICS) was one of them. Improved Cook Stoves (ICS) were first introduced by the Department of Agriculture (DOA) of Nepal in early 1950s. Other organizations like the Research Center for Applied Science and Technology (RECAST), and the Peace Corps also tried to disseminate the idea of ICS in the rural areas in 1970s but could not continue. Later, the Community Forest Development Programme (CFDP) in collaboration with RECAST started promoting ICS. The stoves promoted by CFDP used ceramic inserts made in Kathmandu.

CARE International in Nepal (CARE/N)

Early experiences

CARE International in Nepal (CARE/N) has been involved in various development activities in Nepal since 1978. The CARE/N working policy is based on an integrated approach and community participation in development activities.

Using an integrated approach, CARE/N started promoting ICS in late 1980s as part of the Small Farmer Community Project (SFCP). This was a joint project of CARE/N and the Agricultural Development Bank of Nepal (ADBN). Its major focus was on improvement of farmer-managed irrigation systems followed by forestry and agriculture extension. CARE/N used the ceramic inserts which had been made and promoted in Kathmandu. However, they were not well accepted by the community because:

· The set of ceramic inserts consisting of a number of fragile tubes, which were not locally made, were difficult to transport intact from Kathmandu.

· Some parts could be broken when cleaning the chimney.

· Once installed, if a part of the ceramic ICS was broken it was almost impossible to replace.

Current work of CARE/N

Learning from the drawbacks of the ceramic ICS, improvements were made. The present model of ICS is found to be more appropriate in rural areas as the stoves can be easily made using local materials. Presently CARE/N is promoting the new stoves in its seven working districts in remote areas of Nepal. The Center for Rural Technology (CRT) is providing training on improved Cook Stoves. The status of installation of ICS in CARE/N working areas is shown in Table 1.

Merits of ICS:

The ICS has major advantages over the traditional stoves. The main features are as below:

· Appreciable reduction of smoke in house

- eye irritation and inhaling of smoke reduced significantly
- babies and small children less affected by smoke
- less soot on clothes, walls and house

· Easier and faster to cook

- no chance of soot falling on the food
- constant feeding with fire sticks not required, saving time for other work
- food is burnt less often
- faster cooking

· Fuel efficient

- less fuelwood consumption and thus less fuelwood collection
- efficient use of flame
- sticks get burnt more efficiently
- the effect of wind is nil

· Safer for users, children and babies

- less chances of bums for users
- less danger for children or babies falling into the fire
- less chance of mattresses, beds and roofs catching fire

· Easy to install and repair

- the bricks can be locally made, no need to purchase anything from outside
- broken parts can be easily repaired or replaced
- easy to replicate
- no hi-tech skill is required for installing ICS

Limitations of ICS

· not suitable for large families
· insufficient extra heat generated for space heating during cold season
· soot needs to be frequently removed from the chimney
· it is still possible for thatch roofs to catch fire

Some lessons learned

· In Nepal, the cooking area where the stove is located is regarded as the most sacred place. Strangers are not allowed to go near the stove. It is a sensitive issue and due respect should be given.

· Stove programmes are not a completely new thing for the Nepalese people. It takes considerable effort and time to introduce them as people will not accept them easily. Therefore, the ICS programme should be a multi-year programme.

· The ICS programme should focus more on sustainability than on meeting targets.

· Villagers more easily accept new ideas from neighbours than from outside instructors. A people-to-people earning environment needs to be created.

· Skill and technology should be transferred to the community to give continuity to the programme.

· Local people should be involved in the evaluation and impact studies on the performance of the ICS. The lessons learned in the evaluations are easily shared with neighbours. It is the best method for propagating the use of ICS.

Table 1: CARE/N Project Areas (1990 to June 1996)









Number of ICS installed









Number of persons trained









Energy needs of tourist lodges in two mountain communities in Nepal: A case study

Kamal Banskota PhD, Centre for Rural and Environmental Studies (CREST) and Kamal Rijal PhD, international Centre for integrated Mountain Development (ICIMOD)

Besoins rgques des logis touristiques dans deux rons montagneuses du Nl:

Cet article montre que dans la ron de Ghandruk o promues les rgies de substitution, la consommation de bois est nettement moins importante (30% en moins) que dans l'autre ron, Ghorepani, di L'efficacitnergque est plus vhandruk du fait de l'introduction de nouvelles technologies (cuisson ctrique artir d'ipements de faibles puissances) alors que les ssions de CO2 sont nettement infeure

This case study analyses two areas, Ghandruk and Ghorepani, which are located in the Annapurna Conservation Area Programme (ACAP). Information collected in 1994 from twenty-two community-based tourist ledges in Ghandruk and eighteen lodges in Ghorepani form the basis of the case study. The study was undertaken to assess the impacts of alternative energy and technology.

Ghandruk has relatively better access to new energy sources and efficient technologies whereas

Ghorepani is largely dependent on firewood; both are heavily dependent on tourism. ACAP has introduced a number of fuel-efficient technologies and alternative energy sources in the area in order to reduce pressure on the forests. These include:

· establishment of kerosene depots in several areas
· installation of a 50kW micro-hydro electricity power plant in Ghandruk
· distribution of low-wattage cookers (Bijuli Dekchi)
· incentives for installing solar water heaters, back boilers and improved stoves
· some lodges have also started using LPG

Table 1: Total energy supplied per room per year

Energy use



Firewood (kg)



Kerosene (litres)



Electricity (kWh)



Solar (kWh)



Gas (cylinders)



Table 2: Fuel pattern uses in tourist lodges in Ghandruk and Ghorepani (%)

Energy use


















The energy consumption pattern differs significantly between Ghandruk and Ghorepani, particularly as Ghandruk has access to electricity. In Ghorepani, firewood supplemented by kerosene meets the bulk of the energy requirement. Both these areas are almost equally important in terms of tourism.

The average annual consumption of firewood by lodges in Ghandruk is much lower than in Ghorepani: Ghorepani uses much more kerosene. The total energy supplied to each room each year is shown in Table 1.

Total energy requirements per room per year are shown in Table 2 as percentages.

The primary energy generated in the lodges as a whole has been calculated and this is compared with the useful energy. The results are given in Table 3.

Notice that the efficiency of space heating is very high in both cases, but is higher in Ghandruk than in Ghorepani. The cooking efficiency is almost twice as high in Ghandruk as in Ghorepani; this is because of the improved technologies available in Ghandruk (Bijuli Dekchi, rice cookers etc.), which also has improved stoves and back-boilers.

ACAP has played an important role in the diffusion of efficient technology and new sources of energy. Its intervention has been critical in developing an institutional base for energy planning and forest conservation in an area where tourism plays an important role. Key grassroots institutions have been established for sustaining various conservation related programmes as well as development and dissemination of alternative energy. In addition, a great deal of awareness and training programmes have been introduced.

Forest conservation efforts alone would perhaps not have been successful in the absence of affordable energy and end use technology and alternative energy sources.

Table 3: Primary energy and total useful energy for tourist lodges in Ghandruk and Ghorepani


Total primary energy (GJ)

Total useful energy (GJ)

Efficiency (%)





Water heating




Space heating





















Water heating




Space heating
















Stoves used for cooking, water heating and space heating at high altitude in Nepal - a case study in Jumla

K M Sulpya, Research Center for Applied Science and Technology, (RECAST), Trithuvan University, Kirtipur, Kathmandu, Nepal.

Foyers utilispour la cuisson le chauffage dans les rons montagneuses du Nl: une de de cas Jumla

Cet article montre que les ipement traditionnellement utilipour le chauffage au Nl sont le foyer ouvert pierres (Agenu) et le foyer sans cheminen terre et en pierre. Le Centre pour l'Auto-entraide a introduit des foyers mlliques avec eherninumla. Quoique plus efficaces que les foyers traditionnels, des nomies d'rgie supplntaires peuvent re encore risees par la mise en ouvre de quelques amorations techniques, par exemple en modifiant la taille de la chambre de combustion. Les coe production sont cependant vnotamment ause des frais de transport. Aussi la diffusion de ces foyes a accompagnde subventions

Traditionally, agenu (open fire with an iron tripod) and chulo (closed mod/stone stove without chimney) stoves have been used for cooking and heating purposes in Nepal. The kitchen is normally a small room which is usually not well ventilated to prevent heat loss so the chulo or agenu generally makes the kitchen warm. In winter months besides cooking, space heating is considered a must and the fire is often kept burning round the clock.

The chimney wood-stoves now being introduced in Jumla by the Centre for Self-help Development (CSD) are gaining some popularity. They are used for cooking as well as heating purposes and they appear to be more beneficial and useful than the traditional open fire. The diversity in the types of stove introduced in Jumla is quite remarkable. The technologies used are

· open fire (Figure 1)
· semi-closed stoves (Figure 2)
· closed stoves with chimney and water heating system (Figure 3)

The materials used for stove construction are cast iron and metal sheet. The stoves have two or three pot holes of different sizes and are rectangular in shape and usually without a baffle.

Mild steel sheet stoves are constructed by skilled persons and are good examples of locally produced innovative technology. Cast iron and mild steel stoves are constructed in workshops either in Jumla or in Kathmandu; but they are expensive, influenced by externally introduced technology and have been known to crack over time.

A - DCS stoves with two and three pot holes (dimension in cm)

B - DCS stoves with two and three pot holes (dimension in cm)

Social effects of improved stoves

The improved stoves have created a number of lifestyle changes. The stoves radiate heat to the surroundings and warm the entire room inducing people to sleep around the stove during colder months. People perceive the benefits of reduced smoke inhalation due to the chimney.

In Karnali Trade School the chimney passes through other rooms to provide heat (see Figure 3). in houses that have not installed a metal stove with a chimney, the room is heated directly by a wood-buming open fire.

Programme Set Up and Stove Dissemination

The stove programme was initiated, set up and funded by the United Mission to Nepal and later by the Centre for Self-help Development (CSD). Development Consultancy Services (DCS) is a private company and is run with support from the United Mission to Nepal (UMN). it operates its branch in Jumla mainly in micro-hydro and other support to Kamali Technical School.

DCS started manufacturing cast iron and metal stoves which are more durable and expensive than the original blacksmiths' stoves which were available at that time. The steel sheet was 18 mm thick and the top plate, made of cast iron, was 1 cm thick.

For mass-scale dissemination, having motivated the potential users, CSD provided a 75 per cent subsidy towards the cost of the stove. Prior to dissemination, 25 per cent of the cost was collected from stove users and deposited with the DCS. After two years, because of high demand, and for sustainability of dissemination, the subsidy was reduced to 50 per cent. However, demand for stoves dropped and in 1996, the subsidy was increased to 62 per cent and demand for the stove improved. Stoves made by local blacksmiths were also subsidies in the project areas only. Direct sale of the stoves by the manufacturers did not attract a subsidy.

Cost of the Stove and Affordability

During 1992 to 1995, CSD promoted 366 metal DCS stoves. The cost of the stove to the CSD and to users is given in Table 1.

The cost of the stove is high because of the air freight which is Rs. 40 per kilogram from Nepaljung to Jumla. DCS managed to reduce it to Rs. 23 per kilogram after a special agreement with Nepal Airways. The cost has also increased because of the cast iron plate which costs Rs. 1500.

A local blacksmith has been producing metal stoves since 1989 and has already sold more than 400 stoves for the Small Fammers Development Project (SFDP), CSD, and to local people of Khalanga Bazaar. This type of stove is made from 22mm steel sheet. The cost of the these stoves is given in table 2.

Table 1: Stove costs by stove type and year (DCS model)

Stove type

Weight of stove (kg)


Cost to CSD (Rs)*

Cost to users (Rs)*

Subsidy (%)

3 pot holes (cast iron top plate)


1992 & 93




3 pot holes (cast iron top plate)






3 pot holes (cast iron top plate)






2 pot holes (cast iron top plate)


1992 & 93




2 pot holes (cast iron top plate)






2 pot holes (cast iron top plate)






*40 Rs= 1US$

Table 2: Stove cost by stove type and year (Blacksmith's model)

Stove type


Cost to CSD/ SFDP (Rs)*

Cost to users (Rs)*

Subsidy (%)

3 pot holes (mild steel plate)





3 pot holes (mild steel plate)

1992 & 93




3 pot holes (mild steel plate)

1994 & 95




2 pot holes (mild steel plate)





2 pot holes (mild steel plate)

1992 & 93




2 pot holes (mild steel plate)

1994 & 95




*40 Rs= 1US$

Blacksmith stoves with two and three pot holes (dimension in cm)

Blacksmith stoves with two and three pot holes (dimension in cm

Durability of Stove

The metal stoves with a cast iron top plate were found to be durable; even after 4 years, no cracks have developed. According to the manufacturer, the stoves can last for 10 years during normal use. Other parts, like the chimney and stove body, may last for 5 years depending upon the thickness of the sheet metal used. The Blacksmith's model did not last as long. After 23 years the chimney started tearing off and the top plate sank giving the pot holes an uneven shape; this was caused by the use of thin mild plate.

Stove operation and maintenance

Most cooks do not attend to the fire carefully and lose lots of fire outside the wood-feeding gate (see Figure 1). it is also observed that they do not control the draught or the rate of combustion. In contrast, in the Khalanga Bazaar of Jumla, where fuelwood is scarce and expensive, users attend to the fire carefully and control the power of the stove. Most people in the Bazaar use pressure cookers, especially for beans and meat.

Stove Efficiency

Water boiling and cooking tests were carried out by a cook in field conditions. Table 3 shows the efficiency of the stoves as well as the cooking test results.

The results show that stoves with two pot holes are not only more efficient than open fires but they are also more efficient than stoves with three pot holes. However, the DCS stove with three pot holes consumed more fuel than the open fire.


The metal stoves introduced by CSD do not have significant fuel saving and, in some cases, they use more fuelwood than the traditional stoves. In Jumla, the chimney improved the kitchen environment by making it more smoke free, and increased space heating around the kitchen. The water heating system also helped to produce warm water.

Cooking tests show that metal stoves cook faster than the open fire. In metal stoves, 2 to 3 pot holes can be used at a time. Women also perceived that the metal stove cooks faster.

From the discussions and interviews with both women and men, it was found that the metal stoves with chimneys provided health benefits is and reduced headaches, eye and respiratory infections etc.

Table 3: Cook testing results for stove tested

Stove type

Equivalent food dry wood (kg)

Food cooked (kg)

Wood required to cook 1 kg food (kg)



DCS 3-pothole






DCS 2-pot hole



0 415



Blacksmith 3-pot hole






Blacksmith 2-pot hole






Open fire






People's Attitude Towards the Stove

In Jumla people consider the metal stove with a chimney a necessity, because the stove removes smoke from the kitchen and provides heat to the surroundings. In most cases, it was women who took the initiative to acquire the stove. Out of 64 households, 57 have installed the stoves. Those remaining 7 households are very poor and some have no male adult in their family. Out of 57 households, 4 own more than one stove and are keeping it for their children.

Users of the metal stove said they felt better and more comfortable using the stoves because they cook faster, provide space heating during winter months, they are convenient, smokeless and pose fewer fire hazards, etc. They also felt that the DCS model was expensive but more durable than the Blacksmith model but they did not experience the fuel saving they had expected with the DCS model; nevertheless, they are satisfied.


Forests in the mountainous areas have been an open access resource and wood energy pricing in most areas is lacking. Switching to petroleum based energy may result in less pressure on the supply of the fuelwood but it has to be imported. Thus, from the perspective of sustainable development, for cooking and heating at high altitudes, fuelwood conservation is the only option left in the rural areas.

Research and development activities on high altitude stoves are almost non-existent. Prototypes were introduced without proper investigation. Monitoring and feedback information is still lacking. Financial institutions set up for stoves programmes and promotional institutions for enhancing private sector participation are also lacking. Thus, due consideration should be given to this matter with a view to strengthening research, development, promotion and extension of high altitude stoves.

Household energy in high cold regions of Morocco

by Philippe Simonis, Coordinator of the Special Energy Program (GTZ/CDER) PO Box 509, Gueliz Marrakech, Morocco

ergie domestique dans les zones froides du Maroc.

Cet article consid principalement la ron de IMLIL situdans le Haut Atlas. Le bois en la principale source d'rgie de la plupart des villages du Haut Atlas. L'logie de cette ron ainsi que les aspects socio culturels sont retracdans cet article. Les foyers traditionnellement utilisdans cette ron sont des foyers en cmique sage multiples. Ces foyers ainsi que les fours ain sont gralement construits par les femmes qui s'occupent lement de leur maintenance. Le programme GTZ - CDER (Centre d'udes sur les ergies Renouvelables) vise la ptration des foyers mlliques dont les rendements sont plus vet utilisant le bois comme combustible. Les mesures d'accompagnement notamment la formation des artisans font partie de ce programme

Energy Profile of Morocco

The Kingdom of Morocco is situated on the north-western coast of Africa. It is dominated by the Mediterranean climate which is tempered by the influence of the Atlantic Ocean. Inland, the climate is continental with significant seasonal temperature differences. The mountainous Atlas region is moist with frequent snow falls in winter.

The Renewable Energy Development Centre (CDER) plays a key-role in implementing an energy policy aimed at sustainable development and protection of the environment. With the help of the German Technical Cooperation organization (GTZ), CDER is carrying out several programmes in the fields of biomass and improved stoves. These comprise energy planning (including renewable energy and biomass energy) and the development of technologies with a higher energy efficiency (for stoves and heating institutions and public baths)

Wood energy situation in Morocco

The annual wood consumption is estimated at 7.4 million tonnes with production at only 2.6 million tonnes; a deficit of 4.8 million tonnes annually. Forests are disappearing at an annual rate of 35000 hectares.

Baking top and face of bread

Baking the sides

kettle suspended over Takate

The non-sustainable rate at which wood is being used in Morocco is now being addressed. There are fears that forests will disappear in the near future, especially around cities and villages. In some regions, poor families already use cotton stalks and dried cow dung for cooking.

This article considers mainly the region of Imlil in the High Atlas Mountains, where CDER and GTZ started a dissemination programme on wood stoves. The mountain population consists of Berber tribes who practice different ways of life based on traditional agricultural systems (either transhumant pastoralism or irrigated terraced agriculture); the other on local tourism (for example pilgrimage to shrines). Although adapting to the modem world, the population of the High Atlas region remains closely attached to its traditions.

The locally produced diet comprises cereal grains, vegetables, dairy products, eggs, fowl, meat and walnuts, the main cash crop of the region. The basis of nearly every meal is milled barley, corn or wheat.

Villages, houses and stoves

A village in the High Atlas region comprises a tiered succession of houses overlooking the terraces. Most of the villages are not electrified.

Village houses are generally built of adobe blocks, stone, or more recently, of cement. They are divided in different spaces for men and women, stabling for animals and food storage. The diwan is a room reserved for men and their guests. Lunch or supper is served in the diwan. Women bring in the food and leave; they usually eat in the kitchen or the courtyard. Women collect and store brush wood, firewood and corn roots used for the fire in the kitchen. They keep the fire stoked and ready for use. In the morning, women build the fire and prepare breakfast (milk, coffee, barley gruel or bread).

The "Takate" traditional stove is composed of a ceramic hemisphere placed into a mud support and it is used for several purposes. It serves daily for cooking, (soup, douaz, couscous), bread-baking (a slim pancake in the morning and a more substantial one in the afternoon) and boiling water. The clay insert which constitutes the inner layer of the stove is produced by local craftsman and can be bought in the market.

Sometimes, the shallow firepit in the hearth is lined by granite stones sunk into the floor. An iron grate is often placed over the fire. Alternatively, an iron rack straddling the fire allows kettles to be placed over the fire at various levels so that stews, couscous and other foods can be boiled or steamed at the correct temperature.

Generally wood stoves and bread ovens are made by a particular woman in the family, using knowledge which has been passed down through the generations. She will know how to save wood, combine bread or couscous baking with boiling water for the tea etc. She will also know how to maintain and repair her stoves by protecting them with a mixture of clay and straw.

The kitchen is the energy storehouse of the home. Piles of brush wood, wood and charcoal are stored to one side of this dark room. Women labour in small spaces which are heated by the fire and filled by its smoke. Light penetrates from a small air shaft in the roof. Following the direction of the winds, smoke either exits or fills the house enveloping women and children, which is the cause for different kinds of diseases.

More and more families have a gas burner installed, which is only used for certain preparations or special occasions. Butane gas is distributed in small (3kg) and medium bottles (12kg). The supply is often unavailable in mountainous areas when rain and snow are abundant.

Wood harvesting is one of the most laborious tasks for women although it gives them the opportunity to meet and talk together. It is so important that the strong cord which is used for wood and forage bundling constitutes a part of the wedding gift. Women travel together, starting in the darkness at early dawn with torches and walking up to 10km, often over rugged and steep terrain. They come back in the afternoon with loads weighing 25-55kg for wood or 15-25kg for the very voluminous thorny brushwood. For this reason, women consider wood collection as one of the most awkward of their tasks.

Wood energy constraints and prospects

Fuelwood will remain a main source of energy for most of the villages in the High Atlas mountains. The complex factors affecting its use are acknowledged by Ministries, donors, NGOs, local authorities and the local population.

The main activities actually developed by CDER with the help of GTZ include:

· increasing, improving and updating existing information on woodfuel sources, consumption and more energy efficient technologies

· planning and simulating possible developments in the energy sector (both wood consumption and other renewable technologies)

· dissemination of improved metal wood-saving cooking stoves by; awareness-raising, training of craftsmen and users, commercialization, project monitoring and evaluation

· providing incentives to increase the use of bottled butane gas in rural areas

There are important constraints to such programmes:

· lack of institutions capable of coordinating and steering huge regional dissemination programmes

· absence of decentralized institutions (NGOs) or private companies able to co-ordinate dissemination activities in the near future

· low income level of the population


The measures undertaken in the mountainous regions of Morocco are very important for protecting the ecosystem, maintaining soil quality and helping rural families to find a relatively cheap source of cooking energy. For the goals m be achieved and sustained, projects must be carefully planned and executed in collaboration with local authorities (such as the forestry administration) and associations. The population, especially women, should be involved at every stage of the process and help should be sought from international donors and NGOs.

Status of improved stoves in the northern areas of Pakistan

Muhammad Saleem, Programme Monitoring Officer, The Aga Khan Rural Support Programme, PO Box 506, Babar Road, Gilgit, Pakistan

Situation des foyers amiordans les rons du Nord Pakistan

Cet article souligne que le foyer traditionnellement utilisst un foyer tred mllique consommant environ 20 k/j de biomasse et dgeant beaucoup de fum Le Tandoori peut e consid comme un foyer amorour la cuissori des aliments et du pain. C'est un foyer clos fabriqu partir de l'argile. Les foyers bi-usages (cuisson et chauffage) sont des foyers miliques plus nomes en rgie (15 kg/j au lieu de 20 kg/j). Environ 15 000 de ces foyers ont introduits jusqu'resent. Le foyer amortilisxclusivement pour le chauffage est un foyer mllique produit artir de mataux de recuperation. Ce foyer est surtout rndu parmi les families relativement ais. Diffntes sortes de biomasse peuvent e utilis. Environ 1000 foyers sont fabriques quotidiennement par quelque 50 artisans. Du fait de la crise du bois de feu, les rgies dv des hydrocarbures commencent tre introduites notamment au sein des villages proches des grandes agglomtions


Rural communities at different altitudes in developing countries use various cooking and space heating devices, depending upon the socioeconomic conditions. A growing population and decreasing natural forests have put considerable pressure on the biomass fuel resources used by the rural communities. The situation calls for the development of devices which are most suited to specific socio-economic conditions.

The Northern Areas experience severe cold in winter with heating devices used from 6 a.m. to 10 p.m. for both cooking and heating purposes. In summer, these devices are used for two hours in the morning, two hours at noon and two hours in the evening for cooking and baking only. This paper attempts to highlight some of the traditional and improved cooking and space-heating devices used in the Northern Areas of Pakistan.

The Northern Areas

The Northern Areas of Pakistan consist of five administrative districts. The terrain, which is rugged, uneven and mountainous is spread over an area of 74 square kilometers. The Northern Areas experience two extreme temperatures; a maximum of 45 degC in summer and a minimum of 40 degC in winter. The rainfall varies from 100 mm to 500 mm in a year. Diamer district is rich in natural forests with a forest coverage of 30 per cent of the area. The other four districts have little natural forestry with less than 1 per cent coverage. In some areas, not even a single tree exists.

To meet the shortage of forestry products, the Village Organizations, under the umbrella of the Aga Khan Rural Support Programme (AKRSP), have planted 20 million trees on their irrigated land within a period of twelve years.

The estimated population of the Northern Areas is 10 million. The average household size is 8.33. The population lives at a minimum altitude of 1200 metres and at a maximum altitude of 3200 metres. Much of the area above 2000 metres remains under snow for four months in the winter season. Nearly 95 per cent of the population depend on agriculture for their livelihood.

The families in the Northern Areas prepare three main meals; breakfast, lunch, and dinner each day. In addition, morning tea at 10am and evening tea at 4pm are also prepared for the household members.

Cooking, heating and baking devices

Open hearth

The open hearth is a very old traditional device for cooking, heating and baking which is made from local materials such as stones and mud. It is very cheap and is easily built by the household members themselves. The design of the open hearth varies from area to area (see Figures 1-3). In this open hearth a three-legged iron frame supports the pots and tawa (a circular iron pan for baking bread). All types of biomass fuel, such as firewood, dung, bushes, sawdust, crop residues and mud-grass slices are used. The open hearth is built in an open place in the centre of the traditional house. The house itself comprises a single room which is used for many purposes; sitting, dining and sleeping for all the family members. However, this tradition is gradually decreasing as a result of the introduction of modem living standards for those with more money.

Open hearth common in Gilgit

Open hearth, common in Baltistan

Open hearth, common in Shigar (Baltistan)

The open hearth consumes a lot of biomass fuel. On average, 20 kg (costing Rs.100/40kg) of firewood is used in the open hearth a day (40Rs. = 1US$). Heat cannot be properly retained because a large open hole, with a diameter of 18 inches (450mm), is made in the centre of the roof to allow smoke to pass out of the house. Moreover, heat cannot easily be concentrated towards the pot and tawa for cooking and baking.

The house is filled with smoke which is emitted from the open hearth, which results in health and cleaning problems. The household members have to spend a sizeable amount of money on medicines and detergents.


The tandoor is considered to be an improved device for cooking and baking; it is not used for heating. The tandoor is a closed pot formed from clay (see Figures 4-5). Quite a large amount of fuel is required to heat up the tandoor properly. Once properly heated op. the tandoor is useful for cooking dishes and baking breads (chapattis) in large amounts and for a long time. The tandoor uses, on average, 80kg of firewood a day for baking 300 loaves. It is not used for cooking and baking by small families.

The normal size of the tandoor is 2 feet (0.6m) high and it is 1 foot (0.3m) in diameter at its widest point. It is built in Rawalpindi by trained artisans and is transported to the Northern Areas. The price of average-size tandoor is Rs. 1000 and there is an additional installation cost of Rs.3000.

Traditional Tandoor common in Gojal

Improved Tandoor

Improved metal cooking and heating stove

Cooking and heating stoves are built by private builders who use either metal sheets or recycled sheets produced by cutting up oil barrels. These stoves are placed in the centre of the traditional house, in the room and in the kitchen. The normal size of the stove is 30" × 17" × 7" (800mm × 450mm × 180mm).

The stove has two holes on the top for two pots to be heated at the same time. It has a door at the front for putting in biomass fuel. The improved cooking and heating stove uses all kinds of biomass fuel. A long metal pipe is fixed at one end of the stove to let out exhaust smoke. A considerable amount of heat is retained in the house by using the stove. No open holes or ventilators are needed to let out smoke and fumes (see Figure 6).

These stoves are more fuel efficient than the open hearth, each one normally consuming about 15Kg of firewood a day. The stoves are built by private builders at the district headquarters. There are estimated to be 50 builders in the Northern Areas, who between them produce 200 stoves a day. The price of an average size stove is Rs.450. Most of the stoves are marketed in winter.

Improved metal cooking, baking & heating stove

The Aga Khan Housing Board (AKHB) Gilgit, took initiatives to introduce these stoves in the rural areas through village organizations in 1986. In 1994, AKHB Gilgit employed a trainer from GTZ Peshawar, Pakistan, to train twenty cooking and heating stove builders who were already working in this sector. AKHB Gilgit has, so far, introduced 15000 cooking and heating stoves in the rural areas of the Northern Areas.

Improved metal heating stove

The improved heating stove is built by using metal sheets or by recycling the sheets produced by cutting up oil barrels. The size of the stove is 16" × 13" (400mm × 330mm) with a door at the front and a long metal pipe on the top to vent smoke from the stove. It is mainly used for space heating. It is very common in rich and large families (more than 10 family members) and is used for heating isolated rooms (see Figures 7-8)

Improved metal heating stove

Improved metal heating stove, using saw dust

All kinds of biomass fuel, such as firewood, bushes, dung, sawdust and grass-mud slices are used. The stove in which sawdust is used has a slightly different design; it has a very small hole measuring 3" (75mm) at the front and a large 6" (150mm) hole on the top. The sawdust is put in through the top hole and pressed in such a way that an airway is formed between the bottom front and the top holes. On average, 20Kg of firewood is consumed by the stove in a day.

K. Oil heater

Nearly 1000 heating stoves are manufactured a day by an estimated 50 private builders at the district headquarters. They are sold for Rs. 400 per stove.

Kerosene oil and electric stoves/heaters

K. Oil stove - cum - heater

The price of firewood is increasing daily in the Northern Areas because of depleting natural forests and forest plantations on the irrigated land. Moreover, biomass fuel collection is a time-consuming activity. A single person can collect 40Kg of firewood from up in the high forests in a day. As a result, in cities and in villages very near to the cities, people have started replacing biomass fuel stoves with stoves and heaters fuelled by kerosene oil, LPG (known locally as faun gas) and electricity (see Figures 9-12).

Electric stove - cum - Heater

Electric heater


The communities in the Northern Areas use different devices for cooking, baking and heating, depending on their specific requirements. These devices are: open hearth, tandoor, metal cooking-cum-heating stoves, and stoves and heaters fuelled by kerosene oil, faun gas (a type of LPG) and electricity.

The communities in the Northern Areas are very concerned about the rising costs of biomass fuel and want to save fuel as much as they can. They need special attention from agencies involved in the development of appropriate technologies. Stoves should be designed in such a way that they save fuel, reduce smoke, save time and produce greater heat for corking and warming up houses and rooms.

Improved cooking and heating stoves are hygienic and environmentally friendly. Lung diseases and eye infections suffered by housewives have been considerably reduced by their introduction. A sizeable amount of money is saved from reduced use of detergents and medicines because of the house being free from smoke and fumes. The stove has also indirectly reduced the workload for women, who are responsible for cleaning and washing. Finally, the introduction of the metal stove has reduced pressure on natural forests as a result of savings in biomass fuel consumption.

Improved metal stoves used only for heating are also more biomass fuel-efficient and environmentally friendly, but they only serve the purpose of heating the rooms. Therefore, these stoves are not considered economical for poor families.

High altitude space heating and cooking stoves in Pakistan

Ghulam Umar Sarhandi, Pakistan Council of Appropriate Technology, Islamabad, Pakistan

Foyers pour la cuisson et le chauffage dans les zones aute altitude du Pakistan

Dans cet article, I'auteur souligne qu’avant 1975, diffnts foyers ient utilispour le chauffage et la cuisson. Le Programme de mise en oeuvre des Technologies onomes en ergie devrait permettre la diffusion de 70,000 foyers amorentre 1995 et 1997 dont 15,000 foyers bi-usages (cuisson et chauffage). Ces foyers sont en ml et disposent d'une chemin Ils sont plus adaptaux rons semi-urbaines obois est commercialist l'espace habitable rit. Des amorations techniques y ont introduites comme par exemple la chambre de combustion qui est plus petite. Une grande quantite charbon s'accumule dans la chambre de combustion permettant ainsi de conserver la chaleur La construction de ces foyers n'est accessible qu' es artisans relativement qualifi Il est estimue les nomies de bois sont de l'ordre de 25% par rapport aux foyers traditionnels. La durde vie de ces foyers est d'environ 3: ans en supposant qu'ils soient utilis5 mois par an. En outre les ssions de CO sont nettement moins importantes. Ils restent plus chers que les foyers traditionnels mais sont cependant bien diffussans e subventionn La formation particuliment des artisans est une composante importante de ce programme

Country Profile:

Pakistan, Iying between latitudes 24N and 37N, longitudes 61E and 75E, and having an area of 880000 square kilometres, is one of the most densely populated countries of the world with population of around 130 million. More than 68 per cent of the population live in rural areas. There is diversity in social habits, usually dictated by geographical situation, including cooking, religious beliefs, regional or ethnic practices.

At present, it is estimated that 40 per cent of the total energy used in Pakistan comes from biomass. The per capita energy consumed is very low compared with other countries of South East Asia (Thailand, Philippines, Indonesia, Malaysia etc.).

Depending upon the availability of fuelwood, people use wood, cow-dung cakes, crop stalks, bagasse, some grass bushes and even leaves as a fuel for cooking, but for space heating only fuelwood or charcoal is used. Details of fuelwood consumption can be seen in Table 1.

Heating-cum-cooking devices are widely in use in the colder regions of Azad Kashmir and the mountainous areas of Rawalpindi. They complement the way of living of the people and have, therefore, become a basic component of the household. Mostly, these devices are installed in the bed room, which also serves the purpose of kitchen during the winter. In the semi-urban regions of Swat district and Rawalpindi district, smaller, round heating stoves are used.

Stove use

Heating requirements

Heating requirements vary during the winter season, which spreads over five months. In November, heating is only for four or five hours. In December and March the house is heated all night (eight hours or so) while in January, the heating is required both night and morning. February is the month of snowfall and rains and heating is required for almost 24 hours a day.

Table 1: Share of fuel wood uses in households in Pakistan during 1991

Stove No


Consumption (kg/household/day)

Share of Total consumption (%)


Cooking, space and water heating




Cooking and space heating




Cooking and water heating




Cooking only




Water heating only




Space heating only







Source HESS Energy Wing, Planning and Development Division Government of Pakistan Islamabad 1991

Adoption of multi-purpose stoves

Before 1975, there were exclusively separate cooking and heating stoves or open fires throughout Pakistan. Even now, in some areas, cooking and heating are separate, while in other colder regions, cooking-cum-space heating stoves with chimneys are in general use.

Types of fuel

The same types of wood are used for both cooking and heating stoves except for branches which are only used in cookstoves. This is because wood which burns for relatively long periods is needed for room heating. In one of our pilot areas pine, deodar and few non-cultivated trees are used for heating. Branches of fruit bearing trees are also used for cooking, but not for space heating which requires logs to keep the fire going.

Benefits of chimneys

Space heating varies from house to house depending upon individual choice. The cost of fabrication construction of stoves with chimneys is twice or sometimes three times as high as that of stoves without them. Further, fuelwood consumption in stoves with chimneys is more than that of stoves without; therefore, the running cost is also high. Those who have easy access to woodfuel are more likely to use stoves with chimneys.

Conditions for space-heating use

People in colder areas mainly use cooking-cum-space heating stoves and only a few stoves are exclusively for heating. They are used for cooking breakfast and supper only. Lunch is usually cooked on an outdoor cookstoves unless there is rain or a snowfall during the daytime, then it too is cooked in the living room.

The stove programme:

Structure of the programme

The Fuel Saving Technologies (FST) Programme was originated to consider fuelwood conservation and to help rural women by reducing smoke in the kitchen and to provide education on energy and environmental awareness. The existing programme is a broader one concentrating on both cooking and heating. During the three years from 1995 to 1997, 70,000 fuel saving devices will be produced and disseminated throughout the country. Of these, the number of cooking-cum-space-heating stoves will be around 15,000. Less attention is paid to space heating because only 15-16 per cent of the population of Pakistan lives in colder regions where space-heating is required.

Origins of the stove programme

The stove programme was set up with a modified version of an Indian stove called the 'Nada Chulah'. Before 1988 only 2500 improved cookstoves were constructed in rural and semi-urban areas of Pakistan. A need was felt for a properly organized programme.

A National Seminar on improved cookstoves was organized in Islamabad, the Federal Capital of Pakistan, with the collaboration of the RWEDP of the FAO Regional Office, Bankok. During three days of deliberations a close interaction between the Domestic Energy Saving Project (DESP) of GTZ, Germany and PCAT came into being, which led to a Pak-German project 'Fuel Efficient Cooking Technologies' (FECT).

This project, under which some 40000 metallic cookstove IMPS) were fabricated, was approved in January 1990 for a period of three years. Two improved versions, the Jargan-B3 (JB-3) and the JarganB-5 (JB-5) were developed, tried and disseminated (see Figure I). These had the following advantages:

· Performed well at low as well as at high power.
· Wood saving compared to traditional stove is 25 per cent.
· Cooking time is shorter and PHU is higher.
· Smoke is very much reduced.
· Thick metal sheet provides greater durability.
· Reduced emission of carbon monoxide and smoke provides better atmosphere in the kitchen.

Figure 1: Improved round heating-cum-cooking stove: JB-5

Stove development

The improvement in design was made by reducing the size of the fire box by means of a baffle, which limits the amount of wood fed into the stove and slows down the speed of gases escaping through the chimney.

Materials used

The improved cooking-cum-heating stoves are made with thick metal sheet (usually 22 gauge) including both stove body and grate; the material for chimney construction is left to the end users. Most people use discarded kerosene oil tins for constructing chimney, while some use metal sheet of 24 or 26 gauge. In a few cases, earthen chimneys are used.

Stove Construction method.

Only skilled metal workers can produce the improved stoves. Dies have to be designed and bending machines have to be purchased from the market. These are provided free of cost to the metal workers who are given training in fabricating the stove.

Fuel feeding and ash removal

The baffle alters the speed of the flue gases leaving the chimney and is one of the major factors affecting wood consumption. It makes the size of combustion chamber smaller so that less wood is needed. Sliding doors on the improved heating stove adjust automatically according to the fuel load and they are unaffected by the size of the wood so smoke does not escape through the door.

Operation and Maintenance of the stoves

Compared to a conventional stove, this stove is easy to operate and maintain. Stove tests found that the improved version operated at low power (see Table 2). The speed of hot gases is reduced by the baffle so that maximum heat is given out to the stove body before they leave through the chimney. A large amount of charcoal is accumulated in the combustion chamber which keeps the stove body hot thus reducing the frequency of wood feeding and the attention of the operator.

Figure 2: Chitral Stove

Due to its complex structure, cleaning of the improved stove is difficult. More regular cleaning is needed as the narrow channel for flue gases causes more soot to be deposited in the stove which may cause a blockage.

To avoid smoke leakage, tightly fitting pot hole lids have to be produced.

Further development

· The cooking hole dimensions are fixed already. The users would prefer provision for different sizes of cooking utensils to fit on the stove.

· Quality control needs to be maintained, as stove dimensions, especially pothole lids, are vital for the good working of the stove.

Stove Costs

Capital Cost

The JB-5 stove, made with 22 gauge sheet and weighing 5kg, costs less than the Kalam stove or the Chitral stove (Figure 2). it occupies less space and is therefore more popular among the poorer sections of the population. The Kalam stove is much larger, it is made from 24 gauge sheet, weighs 6kg, and is less popular. The improved version of the Chitral stove made of 22 gauge sheet and weighing 5.5kg is gaining popularity with the rural population.

Table 3: Laboratory test results of 5kg test (traditional vs improved)

Round Stove

Moisture content (%)

Dry wood (kg)

Time taken (minutes)

Average power (kW)

CO reading (ppm)

Traditional stove






Improved stove






Comparison (%)






*Keeping the difference in room temperature at 18°C, 5kg wood lasts longer in improved stove

**The emission of CO in the improved model is 61 % less that in the traditional stove

Running Costs

Heating-cum-cooking devices consume approximately 25 per cent less wood than traditional ones Results from comparative tests carried out in the laboratory are giver in Table 3.


It is estimated that life expectancy of these models is three years, assuming their use for 5 months in a year, depending upon the quality of material. If new 22-gauge steel sheet is used the durability of stove is ensured for a period of 3-4 years. Much depends on its cleanliness; if the stove is properly maintained and ash is removed at the proper time, the life expectancy is as stated other wise the stove may need to be discarded within two years.

Stove dissemination

Multi-pot improved clay stoves are disseminated through the trained workers of PCAT, potters and other collaborating agencies. Metal cooking-cum-heating stoves are disseminated through commercial metalworkers and blacksmiths. From the metalworker the stoves are supplied to NGOs for dissemination, or direct to the end-users. Also, a number of shopkeepers keep stoves in stock.


At present, people usually pay the full cost of the stoves and no subsidies are involved. In a few cases chimneys are provided free to the NGOs who are collaborating with PCAT in the implementation of this programme. In the case of multi-pot improved clay cook stoves, people provide and prepare the clay treated with sand, cow dung and wheat straw which is needed for this purpose. The stove is built by a PCAT worker or a trained worker belonging to a local NGO. The chimney is provided free by PCAT. For metal conking-cum-heating stoves, metal fabricators are provided with a free bending machine, as an incentive. They are given a margin of 10 per cent profit over the fabrication cost and this subsidy is borne by PCAT. Also, the transportation charges from the metalworker to the end user or shopkeeper is home by PCAT. Therefore people are provided with stoves at the fabrication cost.

Table 3: Cooking efficiencies of the the stoves


Big pot
31 cm
7kg water


Medium pot
3kg water


Small pot
1kg water


Traditional Kalam stove







Improved design







Comparison (%)




- 13



Traditional round stove







Improved design







Comparison (%)







Heating-cum-cooking stoves of the FECT Project, Peshawar, Pakistan

Tanveer Ahmad and Sohail Nazir Women Educational and Environmental Network (WEEN) PO Box 25 Abbottabad NWFP Pakistan

Foyers bi-usages con par FECT

Cet article examine les procres pour tester les foyers bi-usages. Les rltats en mati d’nomie d'rgie, d'ssion de monoxyde de carbone et de durabilitont compares aux foyers traditionnels. Les rltats montrent que ces tests sont 'avantage des foyers armor

Heating-cum-cooking devices have been widely in use in the colder regions of the North West Frontier Province (NWFP) of Pakistan for the past decade. These devices were introduced mainly by the metal workers of an area called Gujar Gari. The main reason for their wide acceptability was that they conformed to the way of life of the people and soon became a basic component of the household.

Development of heating devices was started in Kalam in collaboration with the Pak-Swiss project called KIDP in the beginning of 1990. During this phase a number of devices were designed and tested extensively. The research and development in this phase started with the modification of traditional heating devices by improving combustion chambers along with other minor changes. A number of new designs were developed and tested at the Kacha Gari research and development centre in Peshawar. Emphasis was placed on reduction of both fuel consumption and smoke emission and the design of a product which was user friendly at an acceptable price.

Figure 1: Rounded heating stove for communities living in less cold mountain regions.

Based on the basic needs of the targeted population, work on two different heating stove models was initiated; a smaller rounded heating stove for the target group living in relatively low and less cold mountain areas (Figure 1), and a bigger rectangular stove which was aimed at the population living in high mountain areas, who experience harsh winter conditions with temperatures below freezing point for most of the winter. Both these models were field-tested and modified where this was needed.

The latest stove models

The main shortcomings in the improved models included:

· The cleaning of the improved model was reported to be difficult due to its complicated shape
· The stove was seen as too expensive compared to the traditional stoves in the local market

During the field testing, one point became very clear i.e. there was a need to develop different sues and shapes in the heating stoves for different altitudes and ethnic groups within the Swat and Kalam Valleys.

Testing Procedure used at FECT

Different methods were applied to get detailed information about the most important aspects of heating stoves. These aspects included:

· Cooking capacity
· Heating capacity
· Fuel consumption
· Maintenance of fire
· Smoke leakage

Three different approaches were applied to the improved stove models as well as their traditional counterparts. All the tests were carried out in a well-insulated test room, especially designed for the purpose, so that simulation of reality could be combined with standardized test conditions. The fuel wood used in the tests was brought from the area for which the stove was to be developed.

The three different test methods used during tests were:

One hour test

In this method, the stove is operated at very high power rate for twenty minutes. For the remaining forty minutes, operation continues at low power under such conditions that the temperature reached during high power phase does not drop. Temperature and composition of the gases in chimney was measured every fifteen minutes. The amount of wood used during the test is recorded and the whole process is carefully observed.

Savings of the improved stoves at a glance (kg):

Savings using box shape stove compared with the traditional stove

Wood saved in eight hours per stove


Wood saved per day (24 hours operation)


Wood saved per month


Wood saved per season (6 months) per stove


Saving with round improved stove:

Wood saved per eight hours per stove


Wood saved per day (18 hours operation)


Wood saved per month per stove


Wood saved per season per stove


Five kilogramme test

This test method was used to obtain additional information about the relation between fuel consumption, heating capacity and time. The test was carried out to find out the time taken by each stove to consume 5Kg wood. The test method was same as the 1 Kg test except that the 5Kg test was continued until all the wood was finished

Eight hour test

In this test, after 20 minutes of a high power phase, the operation was continued at low power, maintaining the temperature reached during high power phase throughout the test period of eight hours.

After four hours operation, the carbon monoxide content of the air was measured where the person cooking would be located. This was done for one hour using carbon monoxide measuring tubes.

Every 15 minutes, temperatures at four different points of the stove body were measured. These points were:

· Top of stove (over the pothole lid)
· At the side of the wall
· Under the combustion chamber
· Outside of the chimney pipe

The eight hour test, according to our experience, gives a lot of useful information concerning fuel consumption, ease of operation, maintenance of fire, heating capacity and smoke emission etc.

Comments on results

The main conclusions reached using laboratory tests were as follows:

Heating capacity of stoves

It can be clearly seen from the test results that the heating capacity of the improved stoves was far greater than their traditional counterparts

Wood saving

The baffle in the improved stove models is one of the major factors reducing wood consumption. With the baffle, the speed of flue gases leaving the chimney is slowed down and it makes the size of the combustion chamber smaller so that the operator can only feed a small amount of wood. Another factor is the sliding mechanism of the door which helps to retain the heat, whereas the door of the traditional heating stove is left open when the fire is burning. The door of the improved heating stove comes down to just the size of wood fed into the stove. This factor also helps in saving wood (see result of eight hours with open and closed door)

Comparing the results of eight hours test, the wood saving in both the box-shape improved and the round-shape improved stove is around 25 per cent as compared to their traditional models.

Cooking efficiency

The heat is concentrated directly under the pot due to the baffle, so the cooking time of the improved heating stove is shorter and efficiency (PHU) is higher. The improved box shape models give a big difference in PHI,. In traditional stoves, the big pots sit on the pot supports, so there remains a 2cm gap between the pot and the stove which causes the decrease in its cooking efficiency.

Compared to traditional models, the efficiency of the improved box shape heating stove, using big pots is raised by 77 per cent while cooking time is reduced by 52 per cent. For the smaller round stove models, the differences are greater. With small pot sizes, the flames are more concentrated under the pot and the pot hole is completely covered by the pot.

Smoke/carbon monoxide

Laboratory test results show that with the improved models, smoke is very much reduced compared to the traditional models.

Durability of the stove

The improved heating stove models being of thick metal sheet (22 gauge) are more durable than the traditional models (28 gauge). Also the chances of the pot hole becoming distorted are reduced as a metal rod is rolled in its rim.

Operation of stoves

One advantage noted whilst testing the stoves was their operating characteristics at low power. With traditional stoves it is really hard to operate them at low power; the stoves need constant attention and very careful feeding of wood pieces whereas with improved stoves, the operation at low power is very easy.

In improved stoves. the speed of the hot gases is reduced by the baffle, so maximum heat by the exhaust gases is given out to the stove body before they leave through the chimney. In the improved models, a large amount of charcoal is accumulated in the combustion chamber, which keeps the stove body hot, thus reducing the wood feeding and attention of the operator.


Household Energy Programme (HEP) - Co-ordination and Advisory Service, PO Box 5180, 65726 Eschborn, Germany, Tel: 6196 793004-7, Fax: 797325
Editor: Cornelia Sepp

News from Headquarters

Staff Announcements

Dr. Petra Wagner, formerly assistant team leader, has left the HEP-team after three years of successful cooperation. She will continue to work for GTZ, but will be in charge of the preparation of the EXPO 2000 World Exhibition in Hanover as of January 1997. Two new staff members will join the HEP-team at headquarters: Birgit Starkenberg will take up responsibility in February 1997 for project control, contracts and household energy in Uganda and Anke Weymann will be in charge of all projects within French speaking countries.

Trudy Konemund has been appointed team leader for the new project 'Biomass Use and Household Energy in Ethiopia' which focuses on the integration of household energy measures into national sector programmes for resource conservation and health. Vivienne Abbott will be engaged as technical advisor in that same project.

Sahel Regional Bureau

The regional HEP bureau, PED-Sahel, with Beatrix Westhoff as regional co-ordinator has been established in Burkina Faso. The contact address is:

Programme Energie Domestique (PED) Sahel
01 B.P. 1485, Ouagadougou
Burkina Faso
Tel.: 00 226 - 36 30 09
Fax: 00 226 - 31 74 73 email:

Open House at GTZ/HEP Headquarters

HEP acknowledges the importance of public relations, extensions services, and sensation activities in developing as well as developed countries. Thus, an open house event was held at GTZ in Eschborn in June 1996, presenting an exhibition and slide show focusing on household energy and household energy projects.

Integration of a Household Energy Component into the Gambian German Forestry Project (GGFP)

During a two week mission to The Gambia in June 1996, the possibilities for including household energy measures in the community forestry approach of the Gambian German Forestry Project (GGFP) were examined. It was found that favourable conditions for an integrated approach exist. Also, on account of previous stove dissemination efforts, a basic knowledge of stove technology is already widespread in the country. Because established field structures, dissemination strategies and trained extension personnel are available, household energy can be a part of the bigger theme of natural resource management. The effects of working together with community forestry are seen in the support of awareness raising, the facilitation of women's participation in forestry committees, and the strengthening of the self-help approach. The household energy measures will create much-needed immediate or short-term benefits for the population, whereas the beneficial impact of most community forestry activities will occur only at mid-term. It was suggested that household energy sensitisation strategies should be integrated into all steps of the community forestry approach, and the establishment of any parallel structures should be avoided.

Household energy as a school subject

The 'Projet Foyers Ameliores (PFA)' in Bamako, Mali, by Dagmar Orth

People are aware that their natural environment has changed. Vegetation has become much more sparse. Environmental education stresses the links between environmental degradation and energy use. introducing the topic of household energy to pupils in schools is one way of awareness raising.

The household energy project in Mali, Bamako, 'Projet Foyers Ameliores (PFA)' has taken educational needs seriously. The project's extension workers have been working with school children aged 12 - 14 in Bamako since 1990, disseminating their knowledge of improved stoves. These activities were not integrated into the school curriculum previously, but took place in a more or less spontaneous way, depending on the extension workers' visits. It soon became obvious that to spread the activities in a co-ordinated and permanent way, they would have to be made a fixed item in the curriculum. Teachers, and not the project's extension workers, should teach this subject in school.

Since 1995, in co-operation with the Ministry of Basic Education, the 'Institut Pedagogique National' and several other projects working in the field of basic education, the PFA initiated the process of integrating household energy into the curriculum. Links between the subject and existing courses were established, for example in geography, home economics, and languages. A further activity was the participation by the PFA in a work-group concerned with the development of a broader-based course in environmental education.

The procedure for developing such a curriculum is a long and trying one, so as well as working with the formal education sector, the PFA collaborated with NGOs active in the informal education sector, especially UNICEF. In both sectors, the PFA participated in the ongoing training of teachers. In the formal education sector, the project taught trainers for teachers at the two teacher training institutes.

The material developed by the PFA includes:

· a concept for awareness-raising and training for teachers and teacher trainers,
· a specimin lesson for awareness raising of secondary school pupils, and
· a series of lessons for primary school children.

As long as household energy is not integrated into the official curriculum, PFA team members discuss the possibilities of integrating the subject into existing courses with the teachers. The specimin lesson for secondary school pupils and the concepts are presented to them. Where necessary, teachers are trained in building the improved clay stove 'Nafama'. in this case, the PFA staff emphasises the fact that pupils are not expected to be expert stove-builders.

The course on improved stoves places the subject in the wider frame of environmental protection and measures to prevent desertification. It relates pupils' knowledge of desertification to the theme of improved stoves as pan of a basic secondary school geography lesson,

The two pictures illustrate the link between environmental degradation and energy needs. Pupils are encouraged to see improved stoves as one way among others to provide a solution to this problem (Figures 1 and 2).

The series of lessons for the primary schools is conducted in two ways: by practical excursions And by lessons in the classroom. The pupils not only come into contact with the various types of stoves, but they also team to recognise the effects caused by people satisfying their basic needs in a fragile environment.

The experience in Mali was a positive one on several levels. Policy makers in the education sector were already aware of the problem. Teachers welcomed our input and information and the pupils were interested and understood the broader context.

Of course, the influence which younger school children have on their families is not direct or obvious, but older pupils transferred their new knowledge to their families. It is our hope that they will also transfer their new understanding into the families they will start later.

Although the effects of the activities cannot be measured at present - for example by an increase of stoves sold right now - they are a pioneer investment for the future.

Overall, a close and intense co-operation between household energy ventures and basic education would be desirable and an official integration of household energy ideas into the school curriculum should be envisaged for the future.


The Rational Energy Supply, Conservation, Utilisation, and Education Project. in Dadaad Division. Kenya

The arid and semi-arid lands of Dadaab division in north-eastern Kenya play host to thousands of refugees who entered the country during the early 1990s. Following a decision by the United Nations High Commission for Refugees (UNHCR) three refugee camps for roughly 120,000 people, mainly from Somalia, were established.

The area is poor, barely supporting the nomadic people native to the region. As a consequence, environmental degradation in and around the camps has increased, as the additional demand for firewood, poles, and grass has had to be satisfied from nearby natural resources.

The Rational Energy Supply, Conservation, Utilisation, and Education Project, in short RESCUE, commenced operations during 1993 with a view to easing the household energy and environment related problems. During its first year, RESCUE focused on start-off activities, infrastructure development and logistical support, with full scale implementation of planned activities not starting until the second year. These included improving extension strategy and messages, demonstrating ways of restoring the environment, and reforestation measures. Wood fuel saving gooks and user-constructed Rhoda stoves were disseminated in exchange for either work done or tree seedlings planted, with greater importance placed on the latter. Measures to make people aware of the problems covered 80 per cent of the refugee households.

In January 1996, RESCUE entered into its second phase, which is expected to run until December 1998. There has been a significant change in the project's focus of activities, namely an intensification of environmental protection measures and the active involvement and participation of the local host communities and the refugees. Whereas the first phase was aimed at quick results and relief through stove dissemination and propagation of energy saving methods (during the first year malnutrition occurred and the project was in an emergency situation), the second phase adopts a sustainable development approach and centres on the rehabilitation and conservation of the environment.

The main emphasis is placed on the refugee and host communities working together. This is a logical step as these refugee camps are 'consolidation camps' which will continue to exist and will absorb remnants of refugees from other camps scheduled to be closed.

The project has to cope with a number of rather tricky tasks. The most important one is that refugees who view themselves as passers-by must be convinced that investment of labour and effort in environmental protection measures is worthwhile. In addition, mechanisms have to be developed for the host communities and the refugees to work together. Finally, systems need to be developed and promoted for appropriate natural resource management. Ultimately, the participation of the population in natural resource management needs to be assured and incentives for the rehabilitation and conservation of the natural resource base must be provided, especially for the refugees.

RESCUE is facing a number of challenges and it will be interesting to experience its transformation process from a relief/emergency project to a sustainable development project.

Challenges of disseminating stoves in a refugee situation

by Amina Abdalla, GTZ RESCUE Kenya

In most humanitarian relief situations, agencies concentrate on providing the victims with food, shelter, clean water and medical care. Environmental issues in refugees situations were until recently not adequately covered. Often it is assumed that standing fuel stock around the camps is sufficient to meet the need of the displaced. Energy conservation training and dissemination of improved stoves remain the most widely used intervention measures to address refugee impact on the environment. Nevertheless, only small and decreasing budgets are made available to household and institutional energy conservation programmes (Kimani 1995).

Short term concerns frequently take priority over environmental rehabilitation. In the case of refugees, successful stove dissemination is even more challenging, as the planning horizons are short-term and the people are thus less motivated or even reluctant to invest in environmental protection measures.

Stove dissemination:

Stove dissemination projects in conventional development have, over time, learnt that free distribution of stoves and lack of energy conservation training are the major causes for non-sustainability. The fact that refugees are poor and understandably use their meagre budget to supplement items missing in their food baskets necessitates the exploration of refugee resources other than money in stove dissemination. Tree planting and provision of labour for environmental rehabilitation work are some of the exchange commodities tested with positive results.

The lessons learnt through the use of environmental based exchange commodities include (amongst others): the need to introduce a self made stove model, to ensure that acceptability of the stove dissemination strategy is not due to lack of opportunities for refugee labour; to integrate stove dissemination programmes into wider non-seasonally based activities that can ensure continued availability of work, as opposed to environmental rehabilitation work, which is seasonal.

Capacity building:

Linking stove dissemination to energy conservation training

In a refugee setting, where the benefit of any programme is measured by a quantitative approach, the development of energy conservation training is under more strain. The need for training is even higher when the refugee community has experienced little or no fuel shortage in its home country.

Depending on the education level and conservation skills of the community an effective trainer to trainee ratio needs to be decided. The initial ratio needs to be as high as possible to ensure quality information in the beginning and thus avoid possible distortion caused by the healthy refugee rumour machinery.

Simpler energy technologies, that involve participation in design and construction, facilitate the development of the training component. Technologies that involve one to one training as a precondition have higher utilisation patterns.

Stove Production:

Achieving sustainability in stove production through commercialisation

Transport costs and damage to stoves during transportation make the supply of prefabricated stoves to remote refugee camps a costly and unsustainable venture. The question of local fabrication soon becomes essential. We again learn from conventional stove programmes that sustainability in stove production is best achieved through commercialisation. The problem lies with the high stove requirements and short delivery period characteristic of refugee situations.

The prospects for local fabrication is determined by the number of artisans available and whether they are effectively motivated. Motivation can best be achieved through training, offering competitive prices for products, and most importantly, facilitating the supply of quality production tools. A non-subsidised approach needs to be employed, since it results in a cost effective and self sustaining process.


Although many professionals argue that exchange commodities (e.g. stove for work, stove for tress) are a reward punishment approach, it remains the most effective channel through which refugees can be motivated to engage in unpopular activities. It is, however, important that training on proper utilisation of stoves and accompanying energy conservation training precede the dissemination of exchange commodity-based energy saving technologies. Local production of improved stoves at a non-individual level needs to take into account post refugee markets and a sustainable handing over process.

Improved institutional stoves for Sudan schools

by Mohammed E. Abdelrazing: Sudan Ireland Development Co-operation Program, Rufaa, Sudan


The total consumption of wood in the Sudan during 1994 was estimated as 16 million cubic metres, 90% of which was by the household sector (14 million cubic metres).

The efficiency of the traditional stove used in Sudan was estimated to be 12% so more efficient stoves could save thousands of feddans (acres) of forests.

The El Nabti Quranic School has an improved stove which cooks for 1000 students. The main dish for the three daily meals is asida, a thick porridge made from sorghum. This dish is similar to the Kenyan I Ugali and Zimbabwean Sasda. The food is cooked in large pans with curved bottoms. This causes high heat losses when a three stone fire is used. The new stove saves two cubic metres of wood per day.

In Rufaa secondary school in North Sudan (300 students), three charcoal stoves were built to replace the traditional stoves which consumed three bags per day (40kg bag) of charcoal. Using the new stoves, the consumption dropped to half a bag daily. The new stoves saved charcoal, reduced overall cooking times by five hours and retained enough stored heat to keep the food warm till supper (see Figure 1).

The stoves can be used inside the kitchen or out of doors, but the chimney should always be outside the kitchen. The site of the stove should be in a safe, clean and convenient place where disturbance by the wind is slight.

There are two main types of cooking pots which are usually used in Sudan; cylindrical pots with capacity from forty to eighty litters which are made of aluminum and imported: and pots with curved bases with capacities from 80 to 250 litres. These pots are manufactured in Sudan by blacksmiths and they use heavy gauge 1.5-3mm sheet.

In prisons the stove is used for making a sort of pancake from sorghum on a flat rectangular heavy gauge plate. In oil factories, the boiler shape is square or rectangular.

Improved woodstove

General Construction

The firewood stove is constructed of bricks and mortar and it is not more than 0.8 metres high. It has a chimney to produce draught for combustion and to remove the smoke from the kitchen, assisted with a bottle for blocking flue gas. There are two inlets, the upper one through which the fuel is fed and the bottom one to draw the preheated air into the chamber. The fuel inlet has a door to control the entry of cold air.

The method for constructing the stoves is always the same. The shape of the pot holes in the top of the stove is dictated by the shape of the cooking pot, which is usually round, but in the case of the soap factory shown in Figure 2, rectangular containers are used for the oils used in soap manufacture.

Internal Construction:

The grate is made from steel reinforcing rods, 12 or 16mm in diameter with 12-14mm spacing The gaps allow sufficient air to get in and the ash to fall through. To ensure good combustion and heat transfer, the distance from the fuel bed to the pan bottom is critical.

The pot should be a good fit in the hole in the top of the combustion chamber in order to make a seal and ensure that the hot gases go through the passage to the chimney. The small gap between the vertical wall of the combustion chamber and the pot sides is designed to suit the pot to be used so as to give maximum heat transfer.

The passage to take the hot gases from the combustion chamber to the chimney must be the right size and shape, lead up to the chimney and must be kept clear of ash and debris.

The charcoal stove

The four main differences between the charcoal stove and the wood stove are:

· The absence of a chimney in the charcoal stove (see Figure 4);

· The grate is a punched metal sheet instead of the steel bars in the firewood stove;

· The channel between the stove walls and the pot sides must be wide enough to allow the hot gases to escape at the top whilst giving maximum heat transfer to the pot [normally 3-8mm, ed.]

· There are inlets for secondary air.

There have been no laboratory tests carried out to determine the efficiency of the stove, but according to users, the fuel saving is 60-80%.

The stoves have an expected life of more than two years, if they are well constructed and maintained regularly.

Figure 3. Woodfuel burning stove for institutions


Door for In Let of Feeding Fuel


Metal Sheet


Air In Let





Reinforcing Bar


Stove Body


Brick and Clay


Inlet for Feeding Fuel



Door for Cleaning Flue Ash







Circular Channel of Flue Gas



Baffle for Blocking Flue Gas


Metal Sheet


Outlet of Flue Gas





Brick (or Metal Sheet)

Woodstove and char coal stove construction and maintenance

· The dimensions of the pot (diameter and depth) must be measured correctly.

· The construction should follow the dimensions in the design.

· To prevent flue gas leakage's, seal brick layers with mortar.

· Insulate the bottom of the stove with ash mixed with salt and clay.

· The optimum chimney height is about 2.5m but this may need changing when the stove is first tested.

· Pay great attention to the distance between the pot bottom and the grate; for the normal pot (60cm), this should be 18cm for a firewood stove and 13cm for a charcoal stove

· In the firewood stove, the area of the grate can usually he taken as a quarter or a third of the area of the pot bottom Occasionally it will he as little as one fifth.

· The gap between the grate bars should be kept between 12mm and 14mm The bars will need replacing when burnt through.

· Plaster the external stove body with cement after two or three days.

· Ensure smoke passages do not become blocked.

Haiti: Cooking stoves and domestic energy

Editorial summary based on preliminary report by Peter Young of intermediate Technology Consultants and Betonus Pierre for CARE Haiti and the Haiti Bureau des Mines et de l'Energie; April 1996


Haiti is a pan of a large Caribbean island about 800 kilometers long, situated close to Cuba and to the Florida coast of the USA. It has a population of about six and a half million people, increasing by 5 per cent per annum in urban areas and by 0.7 per cent in rural areas. The country originally belonged to the French, it was occupied by the USA from 1915 to 1934 leading to a strong American influence in the country. Since 1994 Haiti has had a democratic form of government.

The climate of the island is humid tropical and the Haitan pan is largely mountainous. Agriculture is very poorly developed and holdings are generally too small to be farmed effectively.

Haiti is perhaps the poorest country in the Central American region with a GNP per head of 370 US$ (compared with Tanzania, which is reported to have a GNP per head of 100 US$). There are few natural resources; bauxite is the main one and there are unexploited deposits of low-grade brown coal. Only 3 per cent of its original forest cover remains, so much of the country is severely eroded.

Nearly a third of the population lives in urban areas and the urban population is increasing rapidly, especially in the capital, Port au Prince. The arable areas of the country have a very high population density of 800 per hectare. Nearly 60 per cent of the population is under 25 years old, literacy is 20 per cent, and school enrolment is only 52 per cent.

Figure 1 Comparative costs of charcoal in major charcoal consuming countries

Energy use

Households consume 92 per cent of all the energy used in Haiti. Nearly all of this (95 per cent) is either firewood or its derivatives. Charcoal accounts for 41 per cent of the fuelwood used, of which nearly three quarters is used in Port au Prince. The movement to urban areas has led to an increased demand for charcoal as the principal fuel.

The remaining household energy is provided by:

· kerosene 2 per cent
· electricity 2 per cent
· liquefied petroleum gas (LPG) 1 per cent

The minimum daily wage is US$2.23 (US$606 per annum). For those earning twice the daily minimum, 20 per cent of this will be spent on charcoal. The poorest 70 per cent of the population, mainly in rural areas, will generally collect fuelwood or other biomass rather than buy charcoal.

Table 1: Wood energy Consumption in Haiti 1990

Charcoal (x1000 Tonnes)

Firewood (X1000 Tonnes)

Wood Energy Distribution %


Informal Commerce & industry


Informal Commerce & industry


Informal Commerce & industry

Port au Prince







Other urban areas







Rural areas







Total per sector











Figure 2: Relative costs per megajoule of useful energy for different types of fuel

Fuel prices and trends

Despite the forestry resources of Haiti being severely depleted, the price of charcoal is considerably lower than in other major charcoal consuming countries (see Figure 1). This is probably due to the poverty-stricken rural economy which causes farmers to supplement their incomes by producing charcoal.

Fuel prices are very much affected by the quantity purchased. Poor households pay more than twice as much as rich households for cooking energy. This is probably due to an increasingly impoverished population who do not have enough cash to buy large amounts of charcoal at any one time. From Figure 2 it can be seen that:

· poor households could halve their current fuel expenditure if they could afford to buy charcoal by the bag, rather than buying enough to cook one meal.

· To cook the same quantity of food, the cost of using kerosene is about one third of that paid by the poorest households who buy charcoal in very small quantities.

Kerosene prices have remained very stable and look set to remain low compared to LPG because of the favourable price structure set by the government for imported fuels.

Economic benefits from switching fuels

From Figure 3, the following can be deduced:

· being able to switch to other forms of fuel energy could save the poorest households up to 8 per cent of their income per year

· for households rich enough to purchase bags of charcoal, butane would not provide savings.

Table 2: Summary of kitchen performance tests on improved charcoal stoves

Stove type households

Number of per household surveyed

% savings per capita

% savings

















Ret: Care & BME August 1995

Choice of appliances will depend on cost, convenience and comfort. The best option is probably charcoal for long slow cooking and kerosene or LPG for rapid cooking.

It has been estimated that 11 per cent of urban households own gas appliances. In energy terms, one tonne of LPG is the useful equivalent of 4.7 tonnes of charcoal. On this basis, 60 000 tonnes of LPG would be needed to replace the total Haitan demand for charcoal (a tenfold increase in current consumption).

Prospects for improved stoves

Charcoal Stoves

Fuel saving assessments using four types of stoves were carried out for low/middle income families with an average household size of seven persons per household. Table 2 shows the savings compared to a traditional charcoal stove. The Ceramic stove is a KCJ type; the Ronderosa (similar to a Burundi stove) originated as pan of the Rwanda World Bank project; the BME stove is one promoted by the Bureau des Mines et de L'Energie; three types of traditional charcoal stove were used (Entole, Potage, Masonry) and no significant differences in fuel consumption were observed so an overall figure is given.

To assess the impact of these stoves, the payback time before the stoves provided real saving were calculated. Table 3 shows the payback time for a ceramic stove and a traditional Entole stove.

LPG Stoves

During the period 1990-93, 80000 BiP stoves, known as 'Ti Cheri' stoves were sold. These are gas stoves which were sold at a very attractive price. The increase in gas stove ownership has not been matched by a comparable increase in gas consumption (and subsequent reduction in fuelwood use). The use of LPG represents, in energy terms, only about 11 per cent of the equivalent charcoal consumption. The popularization of the BiP stove has thus been disappointing in terms of the quantity of fuelwood saved. Gas has provided an additional energy source rather than a replacement and it will take favourable gas prices and improved availability before gas significantly replaces charcoal.

Table 3: Payback time for two improved charcoal stoves

Type of stove



Cost of stove (H$)



Savings H$/household/day



Payback time (days)



Annual savings (H$)




Gas prices are very competitive with charcoal, but the initial outlay for equipment and the recurring cost of a cylinder will remain a major barrier for low income and poor households because of their cash flow problems. However, gas usage will most likely grow at a steady rate, particularly amongst middle income households as they become more affluent.. Kerosene stoves are cheaper than gas stoves. In addition, kerosene can be purchased in small quantities depending upon a person's cash flow situation. In the short to medium term, kerosene stoves should be targeted at low income households whilst the gas companies should continue to popularise gas amongst the middle income households.

Figure 3: Percentage savings achieved by changing fuel supply or using an improved stove

Household energy in a recently electrified rural settlement in Mpumalanga, South Africa

Bernard T Luvhimbi and Harald H Jawurek, School of Mechanical Engineering, University of the Witwatersrand, Johannesburg, WITS, 2050 South Africa.

Wood is still the predominant source of energy for cooking and water heating, but much of it is now purchased, rather than gathered.

South Africa is in the process of rapid electrification. The number of houses newly connected to the grid was approximately 623,000 for the period 1991 to 1993, 436,000 for 1994 and 478,00() for 1995. It is estimated that this programme will increase household access to electricity for the country from 35 per cent in 1990 to 80 per cent in 2010. The households being electrified are mainly those of low income areas. These include - in descending order of income and present access to electricity - the traditionally black, formal townships attached to cities and towns, informal urban communities (shack settlements) and rural settlements.

The effect of electrification on household energy consumption has been studied for several urban and peri-urban communities in South Africa. Very little comparable post electrification information on rural, mainly wood-buning settlements appears to be available. This study looked at such a settlement.

During August and September 1994, an energy consumption survey in a traditionally wood-burning, recently electrified, remote settlement was carried out. The settlement that was studied was Green Valley (24°36'S, 31°01'E), adjacent to Acomhoek in Mpumalanga (previously Eastern Transvaal). Green Valley is an administrative unit of a low income, densely populated, urban like sprawl stretching for kilometers and set in a remote, semi-arid, rural region. Land area per household is of the order of 1000 m2; there is thus no question of subsistence agriculture, though gardening for food is practised, despite frequent water supply difficulties.

The electrification of Green Valley was started in 1990 and essentially completed in 1993. Very few houses were 'wired' in the conventional sense. The majority were fitted with a 'Ready Board', a simplified distribution board into which lights and appliances are plugged directly. The boards are operated by means of a magnetic card with which the customer repurchases electricity at a central pay-point in the settlement.

Data collection

Data was obtained mainly by means of structured interviews based on a questionnaire. A total of 80 randomly selected households was covered. Interviews were conducted in Pedi and Tsonga, the two local languages. Additionally, numerous informal interviews were held. The method involved determining how many households used each type of energy source. For a sample of this size, measurements to determine the exact quantities of each fuel consumed are problematic as they are both intrusive for the households involved and excessively time-consuming for researchers.


Figure 1 shows the percentage of households using various energy sources. All sample households in Green Valley use electricity and 84 per cent of households use wood. There is a sharp reduction in the use of paraffin when settlements are supplied with mains electricity. In the nearby non-electrified settlement of Cottondale paraffin is used for lighting (96 per cent of households), cooking (53 per cent) and refrigeration (7 per cent); in Green Valley it is used for cooking only - the paraffin lamp has passed completely out of use.

The use of dry cell batteries is considerably lower in Green Valley than in Cottondale. This is largely due to the reduced use of batteries in radios. The reduction would have been larger still had not many radios been of the battery-only type. In Green Valley (where all households use electric lighting) candles serve as backups in the case of power failures, or when the pre-paid card is out of credit. Coal, LPG and dung are not used by the Green Valley sample households; coal is not available and LPG is little known. Some dung possibly may have been used, but this was not admitted.

Table 1 shows the percentage of households which use grid electricity for specific functions The main Uses are: lighting, radio for news and entertainment, ironing, cooking and water heating (for washing and hot beverages). The percentage of households in possession of appliances for the last two activities is as follows: full electric stove (5 per cent); double electric hotplate (34 per cent); electric kettle (33 per cent).

Table 1 Percentage of Green Valley households using grid electricity for particular activities


Percentage of households





Radio/music system






Heating water (kettle)




Deep freezing


Cooling house (fan)


Heating house (heater)


Figure 1. Percentage of household using particular energy sources

Of the households using electricity for lighting only, 52 per cent stated that they had too little money to buy other appliances, 30 per cent that they had too little money to run other appliances, or that they had appliances (radios/music systems) but not the AC/DC adapters that permit operation off the mains. Only 8 per cent prefer the use of a non-electrical energy source - wood for cooking.

Of the 84 per cent of households using wood for cooking and water heating, 34 per cent use wood exclusively, 31 per cent use wood supplemented by paraffin, 10 per cent use wood and electricity, and 9 per cent use all three. Wood thus remains a major source of energy.

Table 2 shows how fuelwood is obtained. Purchased wood is obtained mainly from veld clearing operations for agriculture and from vegetation thinning in game reserves suffering from bush encroachment. All purchased wood was veld wood in this study; exotic plantation woods are, however, known to be used at times.

The transition from gathered to purchased wood has also been observed in non-electrified settlements in the area; it reflects the increasing scarcity of free fuelwood from the veld. Table 2 also shows a significant increase in the number of households that do not use wood at all. This is most likely due to the combined effects of wood scarcity and electrification.

Table 2 Sources of wood

Source of wood

Percentage of households

Green Valley 1994

Cottondale 1990

Gathered in veld






Free, collected by hired van



Households not Using wood




In a recently electrified rural settlement in Mpumalanga, electricity is extensively used for lighting and media applications, but less so for cooking and water heating. For the latter, energy intensive activities, wood remains the major fuel.

Comparisons can be made with results from earlier studies in urban and peri-urban areas where it was found that for cooking, water heating and space heating (high energy consumption activities), the 'old', pre-electrification fuels, predominantly coal (for settlements near the coal fields), paraffin (kerosene), and to a lesser degree LPG, remained in extensive use.

Rural households using wood for cooking were found (with a single exception) to use the traditional open fire built on the ground. There have been several attempts locally, and numerous programmes elsewhere, aimed at the development of low cost, wood-burning stoves that are more efficient and that pollute less than open fires. Woodstove programmes thus remain relevant in the face of rural electrification. With the increasing scarcity of traditional veld wood there is a major energy transition from gathered to purchased wood.

Improved Tunisian domestic bread ovens: Flying saucer lids save 50 per cent fuelwood

by Hanns Polak, (GTZ/Agence pour la Maitrise de l'Energie), BP 230, 7121, Barnoussa, El Kef, Tunisia

With its two and a half million inhabitants Tunis is today one of the big cities of the Mediterranean. It has been quickly growing over last decade, but despite that, Tunisia is a rather small country of barely nine million people.

Tunisians have maintained a taste for rural life. 'Bread' in Tunisia means mostly the French 'baguette' produced in large quantities in central bakeries in each town. It is cheap - less than 20 US cents for a pound - as its price is fixed by Government. For most people the Arabic word 'chobbs' is reserved for the 'real' bread which is still made in at least 500,000 tabouna ovens all over the country. It is flat and round; that cake shaped little something owes its aroma and taste and its golden brown crust to whole wheat flour and the fine scent of pine firewood. Baking requires five to six kilos of wood for each firing. Even though LPG has replaced the three stone fire for cooking, a tabouna still remains the heart piece of a Tunisian household, representing traditional values and continuity.

A women's technology

Baking bread in Tunisia is a woman's affair. In each village there is usually one lady who specialises in making the barrel shaped ceramic body of a tabouna oven. The procedure needs several days. After soaking the clay for two days the shaping is done by hand, without a potter's wheel. The barrel needs to dry for three to four days before it can be baked in the fire. The baking is done by covering the inside and outside of the oven core with a heap of dry twigs. These are burned reaching temperatures of between 500°C and 800°C which bake the clay.

After the barrel has been brought to the place outside the house where the tabouna oven will be finally installed, the housewife takes over. She insulates the outer surface with a mixture of straw and loamy soil, leaving two, three or four air holes at the bottom of the stove. In a few tabounas, which are constructed completely underground, there are no air holes at all. There is never a grate at the bottom of the tabouna; the ash is swept out through the holes or is extracted using a flat shovel. The mouth on top of the tabouna remains open to put the fuelwood and later on the bread into the oven. In the traditional way it is not covered while heating the oven.

If firewood is available, the housewife will start baking at once; usually, she will have to go and look for fuel. Groups of three or more ladies go together to collect firewood and shrubs. If the area is sparsely forested, they will leave in the early morning and return in the late afternoon, each carrying a load of about forty kilograms.

Although arduous, collecting fuel does allow women a chance to get away from the constant supervision of the menfolk in the family; this is the only time when womenfolk do get away from the family home. Fuelwood is an increasingly scarce commodity: there remains hardly anything burnable to gather, especially in the vicinity of villages and towns.

Many women use agricultural residues or they collect shrubs, such as rosemary, which are easily uprooted and may still be found after the forest wood has all been taken. However, this leads to erosion as the winter rains wash away the soil which had been held together by the shrubs and the next year the problem is even more severe

Tabouna lid

Even in already deforested areas 89 per cent of the households meet their energy requirements with approximately four tonnes of biomass per year. About 44 per cent of it is needed for making bread in the tabounas. At least one half of the tabouna-using households have to buy fuelwood in addition to what they collect.

Equipping the tabouna oven with a lid was the most promising solution to reduce the consumption of firewood. The lid is made out of sheet steel and is fixed by a hinge on to the tabouna. When the tabouna is in use, the lid is closed, thus retaining a large proportion of the energy that is normally lost with the traditional tabouna.


The project team sells more than 4000 lids per year and has developed a social marketing strategy to commercialise the lid. One of the field workers relates;

'In the beginning it was very difficult to convince the women... they were arguing that the taste of the bread would change when using a lid over the tabouna. And it was even more difficult to convince the men to pay the price of 9 dinars [about 9US$] for something which would in their view only serve their wives”

Over the two years work the team has developed a social marketing strategy to commercialise the lid.

The first thing we discovered was that the lid needed to be more attractive. The people wanted not only something that would save their time and money, they wanted something nice.

By using standardised moulds, imported sheet steel and a simple press, operated by a lorry jack, local blacksmiths can produce attractive lids that resemble mini flying saucers. The tabouna was converted into a real modem baking oven.

Marketing the lid

The lid was named 'Salha' a word that means in Arabic, 'useful' or 'good for'; a famous popular song carries the same title.

Demonstrating the usefulness to a target group of 150000 households was a more difficult job. As the field worker explained,

'...soon we realised that we were simply too small a group to go into each and every douar... without the help of other organisations and many other vulgaristrices [field workers] we felt we would need a hundred years to popularise the ".salha".'

Local agricultural advisers, NGOs, blacksmiths and sellers of household appliances were drawn into the scheme. They all needed to be motivated, trained and equipped with demonstration tools. Once the communication between customers, producers and regional agents was installed, radio and TV spots were produced and broadcast. Every possible event like environmental or agricultural fairs and seminars and local markets were used to advertise the lids.

Development from project to enterprise

'Before we discovered the mechanisms of the market the relationship between us and our target group was clearly defined: we were a rich project and they were the beneficiaries.'

This role led to a perception that the lids would be supplied free of charge. In order to supply lids to an increasing market it became essential to convert the project from a charitable project to a small enterprise.

'We do not say any more beneficiaries we talk about customers.'

Beneficiaries became customers; subsidies were ruled out; the lids are now sold at the commercial price. The enterprise makes a small profit as sheet steel and hinge material are free of tax and duty and the prices are fixed for a period of time. Although the project still depends on government finance, it works as an enterprise, depending on profits.

'We work like an enterprise our financial means are scarce so we have learned to employ existing partners.'

Politicians and administrators are used to promote the benefits as they are shown to be caring for the environment and their people. Controlling quality and price is necessary to avoid producers and customers being dissatisfied. External support will still be needed for a long time before all functions are taken over by private entrepreneurs.

Mumu: A traditional method of slow cooking in Papua New Guinea

P A Sopade, Food Technology Section, Department of Applied Sciences, University, of Technology, Lae, Papua Ned Guinea

One of the traditional techniques in Papua New Guinea is cooking with the mumu. The mumu is an earth oven that is formed by heating stones which are subsequently put in with the food or arranged around and on the food. The heat in the stones is transferred to the food to cook it. The earth oven is known by various names amongst the South Pacific islanders:

· in Samoa, Tonga and Cook Islands it is umu
· in Tahiti it is ahimaa
· in Solomon Islands it is motu
· in New Zealand it is hangi

Generally, black river stones are used and hard wood is preferred as fuel. All sons of food are cooked in the mumu at the same time, but usually the more delicate ones are put on top. The time spent cooking depends on the quantity of food being prepared; it can take anything from one hour to overnight. Mumu is often used during ceremonies, but even households with modem ovens will use mumu on occasions.

Types of Mumu

Papua New Guinea is a land of contrasts; from swampy plains to high alpine mountains and broad upland valleys. Mumu appears to be more common in the highlands, where pottery is very limited. The following types of mumu have been identified;

Rabaul mumu

Alotau mumu

1. Rabaul

In Rabaul a pit is usually dug in which the stones are heated. The size of the pit and the quantities of stones and firewood are dependent on the quantity of food to be 'mumurised'. While the stones are being heated, food is prepared with coconut cream and wrapped in banana leaves. The banana leaves are conditioned over the fire which is heating the stones. The charcoal is removed from the heated stones, and the wrapped food is placed on some of the hot stones. The remaining stones are place on top of the wrapped food before covering the mumu. With banana leaves and jute bags, neither sand nor earth is used and it is usually left for about four hours. All the foods are cooked together and the food is baked rather than steamed as the moisture in the mumu is limited to that held in the leaves and the food. The temperature of the food can be as high as 250°C.

A similar type of mumu was observed in the Western Province (Daru) but no pit was dug and tree bark was used in covering the mumu instead of banana leaves.

2. Alotau

This type of mumu is referred to as dry mumu because, even though the foods are wrapped and cooked together no coconut cream is used in the food preparation. A pit is dug and when the stones are hot. the charcoals are left amongst the stones. The food is wrapped as in the Rabaul mumu and it is put on the hot stones. More hot stones may be put on the food, but more leaves are used to cover the food before the dug earth is used to complete the covering and keep the heat within the mumu. Smoldering firewood is placed on the earth cover to keep the top layer hot.

The additional heat from the top ensures that a high temperature (greater than 200°C) is maintained in the mumu throughout the duration of cooking. The hot charcoals complement this. This relatively constant high temperature is needed to ensure that the food is properly cooked as the absence of coconut cream will reduce heat conduction. As with the Rabaul type. baking is the predominant process.

3. Goroka

This type is typical of mumu in the Eastern Highlands Province. The stones are heated in the pit and most of the charcoal is removed afterwards. Banana leaves are put on top of the stones and the food is wrapped in separate segments. Hot stones may be put in or on to the wrapped food and earth is used to complete the covering. Water is then poured on to the hot stones through a special opening. This generates steam within the mumu. More earth is used for the cover to keep the steam inside. The cooking duration in the Goraka mumu is the shortest, possibly because of the steaming effect. The food appears less baked than in the other forms of mumu and the temperature of the food is usually below 100°C.

Goraka mumu

Mount Hagen mumu

4. Mount Hagen

A different type of mumu is found in the Western Highland Province. A relatively deep pit is dug which is conical in shape. Stones are heated on the ground away from the pit, the bottom and sides of which are lined with banana leaves before some hot stones are put in. Food is transferred separately into the pit and the hot stones are put directly in the food. Coconut cream is not used and neither is water poured on to the hot stones nor are the food segments wrapped in banana leaves. When all the food has been put in, the protruding leaves from the sides of the pot are used in the final food wrapping. Grasses and additional banana leaves are used for the final covering to keep the heat within. Baking is expected to be the predominant form of cooking.

The temperature in the mumu can be as high as 250°C and because of contact between the stones and the food, the food approaches the temperature of the stones. The high food temperature demands that the mumu is uncovered within a short time to prevent over-cooking. It is unusual for this type of mumu to be left overnight. A similar type of mumu has been recorded in Western Samoa, but coconut cream was not used and no pit was dug.


Mumu is pan of the culture in Papua New Guinea and the field study revealed that mumu is cherished by the people. Mumurised foods are reportedly rich in flavour and are preferred to foods from conventional ovens for this reason. In theory, cooking foods in a mumu seems convenient, but in practice it is very labour intensive. Concerns have been raised concerning the fire hazard and environmental implications of the mumu materials. However, the major concerns must be the undercooking and overcooking of food and post cooking contamination, as well as migration of materials from stones to foods. At present laboratory tests are being used to examine temperature distribution in the types of mumu discussed above and associated microbiological issues.

Reducing the risks of poisonous emissions from stoves

Grant Ballard - Tremeer and Harald H Jawurek, University of Witwatersrand, Johannesburg, South Africa.

To keep warm in cold climates, fires and stoves are needed for space heating as well as for cooking. These fires are often in rooms with little ventilation and they bum for long periods. People are thus exposed to high levels of combustion emissions for a long time - the health impact of these emissions on the users is therefore particularly severe.

The health effects from combustion emissions range from headaches and breathing difficulties to death. These effects may be immediate or occur after being exposed to the pollutants for a long time. Some symptoms may show up only many years after exposure. The effects depend upon the type and quantity of the pollutants, the duration of exposure to them, and on the age and health of the person exposed. There is increasing evidence that chronic exposure to carbon monoxide (CO) constitutes a long-term health risk.

At the University of the Wilwatersrand in Johannesburg, South Africa, the CO and smoke emission patterns have been recorded for a number of cooking devices including the traditional 'three stone' fire, as well as a number of improved stoves. It was found that enclosed stoves all have greater stove efficiencies than the open fire but also had greater emission levels.

In an attempt to improve efficiency, thermal contact between the fire and the base of the pot has been increased in improved stoves by enclosing the fire, but this results in the combustion gases being less completely burnt. In addition, in an enclosed fire, the flames are 'forced' on to the base of the much cooler pot, thus quenching them and causing 'freezing' of the volatiles and their emission in partially burnt states.

Emission rates were recorded for CO and smoke every ten seconds throughout a bum cycle; this involved heating water to boiling point rapidly and then simmering for 30 minutes. Figure 1 shows room concentration of CO for a one-pot metal stove with ceramic insulation which is top fed. Notice the high room concentrations reached for the metal stove. The line shown at 0.1g/m3 (equivalent to 87ppm) is the level of the 15 minute World Health Organisation air quality guideline for Europe. Notice that both the three-stone fire and the metal stove exceed this level for most of the bum cycle. After 40 minutes, room concentrations for the metal stove are twice as high as for the open fire. From the above discussion we offer the following recommendations:

Figure 1: CO concentration in a room with poor ventilation

· For space heating, improved stoves must have chimneys so that combustion gases are removed from the dwelling. The Indian Chulha with a chimney, although its efficiency is low (as can be expected for large mass mud stoves) is a good example. Mud stoves without chimneys are not recommended.

· Do not assume that improved stoves without chimneys are safer than the traditional open fires. Enclosed stoves in general emit higher levels of poisonous gasses than three-stone fires. Stoves which are 'fed' through the same opening as that which supplies air for combustion have the danger of being over-stoked (in an attempt to prolong burning). The more fuel in the combustion chamber, the less space there is for air, and emissions will therefore increase significantly. Stoves providing combustion air principally from beneath the fire through a metal or ceramic grate can clog with ash and gradually cause the fire to smother; again greatly increasing emissions.

· Particularly large quantities of poisonous fumes are emitted during stove lighting and refueling because cold pot sides and stove sides cool the flames and result in less complete combustion. Because of this, portable stoves without chimneys should be lit and operated out of doors for at least ten minutes before being brought indoors. This practice is frequently followed in South African informal settlements with coal-burning braziers, 'Mbaulas', made from 25 litre drums. Refuelling indoors is dangerous (although peak emissions after refuelling are usually lower than after initial ignition owing to reduced quenching on the sides of the stove). No fire (even a glowing one) should, however, be operated in a room with poor ventilation.

· Overall efficiency can easily be improved without reducing combustion efficiency by raising the fire off the ground by means of a grate. This improved three stone fire has an efficiency comparable with enclosed stoves (21 per cent) but with much lower emissions.

Update on biogas in Nepal

Summary from Biogas and natural resources management (BNRM) Nepal'

With the rapid depletion of forest resources in Nepal, alternative sources of energy must be sought. Biogas is one of these sources, which not only saves firewood but also has the potential to increase soil fertility, improve sanitation and reduce the workload of women.

In November 1992, an agreement entitled the 'Biogas Support Programme (BSP)' was signed between His Majesty's Government of Nepal and the Netherlands Development Organization. The long term objectives of the BSP are:

· to reduce the rate of deforestation and environmental deterioration by providing biogas as a substitute for fuelwood and dung cakes in order to meet the energy demands of the rural population;

· to improve health and sanitation of the rural population, especially women. This was to be achieved: by elimination of smoke produced during cooking on firewood; by reduction of the hardship involved in the collection of firewood; and by stimulation of better methods for dealing with dung and night-soil;

· to increase agricultural production by promoting an optimal use of digested dung as organic fertilizer..

The programme was divided into two phases. The short-term objectives, to be reached by July 1994, were:

· to construct 7000 biogas plants;
· to make biogas more attractive to small farmers, and farmers in the hills;
· to formulate recommendations on the privatization of the biogas sector in Nepal.

The second phase, started in July 1994, has the following aims:

· to install 13 000 quality biogas plants using both the implementing agency and private construction companies;
· to support the establishment of an apex body to co-ordinate the different actors in the biogas sector.

Dung is the main potential source of biogas. The production of biogas is limited by altitude and access to water. The number of households with cattle and or buffalo in Nepal in 1992 was calculated as about two million. Installation of biogas is technically possible for 65 per cent of these households (about 1.3 million), with average digester size estimated as about seven cubic metres.

The project to date

Six different sizes of digester have been installed ranging from four to twenty cubic metres total capacity (digester plus dome).

These plants work well for households with cattle but have not proved successful for community biogas plants, mainly because of social factors.

By providing a subsidy whose value was the same for all sizes of plant, small farmers with few cattle were encouraged to take part in the scheme. A larger subsidy was given for those living in the hill districts as the transportation costs of moving the digester on to their farms was perceived to be greater.

At present, twenty-three biogas companies construct and install biogas plants and eight more have been approved to construct them. Recently, the Nepal Biogas Promotion Group has been established. Promotion, training and extension will be taken up by this group in the near future. NGOs have entered into agreements with biogas companies to promote biogas in their regions. Two banks have recently decided to invest in the scheme, and this has helped to finance the programme.

Strong emphasis has been given to the quality of construction, maintenance and operation of the biogas plants.

Impacts and benefits

Several studies have shown indoor air pollution and smoke exposure in rural Nepal, expressed in respirable suspended particulates (RSP), carbon monoxide (CO) and formaldehyde (HCHO) to be among the worst in the world. Smoke is one of the major risk factors for acute respiratory infections in infants and children and is a major cause of child mortality in Nepal. The installation of biogas plants has resulted in significant health benefits. The main positive effect is on the level of indoor air pollution. Eye ailments, commonly associated with smoke-filled rooms have been reduced by the reduction in smoke.

It has been estimated that just over three hours a day can be saved by an average household by installing biogas.

Women who use biogas express great satisfaction with it. They are able to do other activities as the cooker does not require constant attention. In summer, the heat produced is less; however, in winter they miss the extra warmth.

Biogas can only be used by farmers who own cattle. The poorest in society therefore do not benefit directly. Nevertheless, by promoting biogas use, pressure on the more traditional fuelwood sources is reduced and if fuelwood is more plentiful, the poorest people may be indirect beneficiaries.

Research and development

Research into integrating a wood/charcoal stove into building design

N K Bansal and M S Bhandari, Centre of Energy Studies, IIT, Hauz Khas, New Delhi - 110016, India


An idea for integrating a cooking stove in the kitchen into the design of a building has been investigated for space heating in cold climatic conditions. The exhaust gases from the cooking stove are made to flow through a cavity wall, which acts like a chimney. The wall stores the heat during cooking hours and keeps the inside space at a comfortable temperature provided the heat loss rate from the building does not exceed 0.5 W/m2degK.


In many regions of Nepal and India there is a need for heating round the year. This is usually achieved by using a wood stove which is also used for cooking. The usual three stone fires, have now been replaced by cleaner, more efficient cooking stoves. Although stoves of this type are designed with a chimney, most of them are not integrated into the building design. In this paper, we examine the possibility of integrating an efficient wood stove into a building, which may provide both cooking energy and the energy for space heating.

Stove design

Table 1 gives the amount of fuel needed to cook 1 kg of various foods. It is seen from the table that, theoretically, 18gm of wood per kilogramme of food cooked is required for cooking, but in practice approximately 268gm of wood is used up in the fire. Some stoves have been considered in detail to determine the quantity of energy lost during the process of combustion and cooking.

Stove efficiency

For improving the overall efficiency (PHU) of a stove, a number of factors should be considered:

Combustion efficiency: the maximum amount of energy which can be converted into heat as a percentage of the calorific value of the fuel.

Heat transfer efficiency: the maximum amount of energy which is transferred to the pot. This includes conductive, convective and radiative heat transfer processes.

Control efficiency: the mechanism which allows only as much heat to be generated as is needed to cook the food.

Pot efficiency: the characteristics of the pot which affect the proportion of heat reaching the food through the pot.

Cooking process efficiency: how efficiently the heat which reaches the food converts the raw food into cooked food. Combustion and heat transfer efficiencies are often combined for convenience and these are termed the thermal efficiency of the stove. When these are combined with the control efficiency and the pot efficiency, the efficiencies combined together are called stove efficiency.

Heat transfer processes

Heat conduction: when cooking begins, the walls of the stove are cold. With time, they warm up at a rate which is dependent on both the weight of the walls and their specific heat. Lightweight walls warm up quicker than heavier walls.

Heat transfer to the pot by convection: when a pot is being heated by hot gases leaving the fire, the factors which affect the amount of heat reaching the pot by convection are:

· the area of the pot which is in contact with the hot gases;
· the difference between the gas temperature and the temperature of the pot.

To increase heat transfer to the pot by convection three things can be done:

· the temperature of the hot gas can be increased by the choice of stove and by controlling the amount of air that enters the stove;

· increasing the area of the pot exposed to the hot gas. The pot support should be small and strong, occupying a small area and allowing the hot gas flame to rise up around the pot and contact the surface;

· the maximum heat transfer coefficient should be increased. This can be done by increasing the velocity of the hot gas.

Heat transfer to the pot by radiation: the radiative heat transfer to a pot depends on the temperature of the tire bed, the areas of the pot and the fire bed, and the distance between the two. To heat the pot more effectively by radiation the alternatives are:

· increasing the fuel bed temperature and thereby increasing the heat radiation from it;
· lowering the pot and thus reducing the distance between the pot and the fire bed;
· increasing the area of the pot 'seen' by the tire bed.

Figure 1: Hypocaust system integrated in a building

Figure 1: Hypocaust system integrated in a building

Combustion efficiency

Combustion of biomass is an extremely complex process involving chemical kinetics, heat processes, molecular diffusion and other phenomena. The most important parameters in wood combustion are the moisture content of the wood and its calorific value. Usually the calorific value per kilogram of any type of wood does not vary by any significant amount from any other, though the densities can be very different. The density does not affect the stove efficiency. Moisture content affects both the calorific value and the rate of burning very significantly.

Wood is typically composed of 80 per cent volatile material and 20 per cent fixed carbon and it is these percentages which determine the calorific value. In wood combustion, when the temperature reaches 100°C, the water is boiled out. From about 200°C, the hemicellulose begins to decompose, followed by cellulose decomposition. At about 300°C, decomposition becomes extensive when only 8- 15 per cent of cellulose and hemicellulose remains as fixed carbon and the rest is released as volatile gases. As volatiles escape the wood, they mix with oxygen in the air at about 550°C and ignite to produce a yellow flame. The flame not only radiates energy to the pot but it also maintains the combustion process. Burning of volatiles accounts for two thirds of the energy released by fire and the burning charcoal left behind accounts for the remaining third. A variety of techniques are used to increase the combustion efficiencies:

· use of grates which allow better mixing of air with fuel bed
· preheating of incoming air
· optimizing the shape of the combustion chamber
· insulating the combustion chamber

Heat of exhaust gases and building design

The escaping hot gases from a wood charcoal stove arc at a high temperature, between 300°C and 500°C These flue gases can be made to flow through a hollow wall in a 'hypocaust system', as shown in Figure 1 which is a conceptual drawing of a cooking stove integrated into the building design.

In the hollow wall, a cavity 50mm deep is created. A room of 10m2 floor area and a height of 3m, adjacent to the kitchen, has been considered. A daily variation of room temperature has been simulated and compared to the corresponding outside temperature at the same time of day. The performance of the experimental stove has been studied keeping all these parameters in mind.

To ensure good combustion the amount of air supplied for each kilogram of wood burnt should be at least 7m3. For most stoves used in developing countries, 1 kg of wood is burnt in about an hour, which corresponds to a power output of 5.5kW.

Results and Discussions

The following conclusions have been drawn from this study.

· the largest heat losses occur (1+ 42 per cent) through heat conduction into the walls of the stove

· the loss of energy into hot flue gases accounts for 22-39 per cent of the total input to wood stove

· incomplete combustion amounts to about 8 per cent

· typically half the energy entering the pot is lost in the form of steam. This is the energy lost at the point of use and mainly depends on the design of the pot.

The results of the hypocaust wall show that to provide adequate heating, it is sufficient to use the stove for 2 hours in the morning and 2 hours in the evening. The most important pan is to keep the building's envelope U-value at 0.5 W/m m20K which corresponds to a 5cm thick layer of insulation or an 80 cm thick mud wall

Table 1: Energy and theoretical amount of wood required for cooking food


Sp. Heat KJ/Kg °C

Temperature change °C

Energy required for chemical reaction kJ/

Food cooking energy kJ/kg

Wood equivalent gm./kg of cooked food




















2.01 -3.89

















* Includes sufficient water for cooking but none for evaporation
** For wood with a calorific value of 18 MJ/ kg

A Better Bonfire Kiln for Stoves and Pots

by Moses Agumba and Vivienne Abbott. Intermediate Technology Kenya 1996

The manual explains how to build, use and maintain a better bonfire kiln. It is intended for potters, women's groups engaged in pottery activities and agencies who work with potters.

The better bonfire kiln is a simple structure built from locally made bricks. The kiln is constructed on a slightly raised foundation to protect it from damp. It is a brick cylinder built over five firebox channels. For each firing, a mud dome is made over the kiln to keep in the heat.

It is 'better' because:

· it holds the heat - so it requires less fuel
· it heats up and cools down slowly so less pots and stoves crack (less than 10%)
· it distributes the heat more evenly so pots and stoves are more evenly fired
· it is made of local bricks using local skills - so it is cheap to build
· it is easy to build, use and maintain

The booklet is written in plain English with all technical terms explained and with clear drawings of the kiln and construction processes and the equipment needed. It is one of a series of booklets being produced by IT Kenya about household energy in East Africa

Review by Ian Grant

Measuring successes and setbacks: How to monitor and evaluate household energy projects

GTZ/HEP and international Technology Development Group (ITDG) with The Foundation for Woodstove e Dissemination (FWD) (1996)

This publication emerged out of a joint project between GTZ, ITDG, FWD, and, originally, the Association de Bois de Feu. It is the result of a collaborative effort on the part of household energy specialists from fifteen countries working together for over four years. The manual has been field tested in twelve projects in Africa, Asia and Central America.

The manual addresses the need for training materials in monitoring and evaluation (M&E) of household energy programmes, responding to requests for assistance from project partners. Through the use of the manual, information about why household energy programmes succeed or fail can be obtained. With the manual, the editors hope to equip project staff to use M&E to give beneficiaries a clearer voice in the context of household energy projects.

The manual offers advice and ideas on planning and conducting M&E and suggests methods for carrying out the various tasks. Nevertheless, the authors do not see their handbook as a definite set of guidelines. They caution that the guidelines have to be adapted to each project's objectives and the individual socio-economic, political and technical environment.

The second part of the book shows practical ways of how to carry out M&E in household energy projects. This part is subdivided into three major sections according to the field of intervention;

· M&E for management
· M&E with producers and distributes
· M&E with users

After a short introduction for each section, concentrating on the key questions, a complete list of suggested indicators (i.e. what to measure) is compiled in distinct and comprehensive tables. Further columns present what should be considered and what should be done with the information. The authors emphasise that before developing and using an monitoring and evaluation system, each individual project must first analyse its information needs, i.e. 'who needs which kind of information at what accuracy for what purpose and when?' It is thus obvious that the lists can only provide a framework.

In conclusion, this manual should be very useful for everyone working and participating in household energy measures, i.e. managers, staff users, producers, researchers, partner agencies, and donors. Hopefully, it will lead to a wider acceptance, increased application and improved participation of M&E methods in household energy projects. With the assistance of this publication, important insights on successes, setbacks, and failures of projects can be gained. The manual is based on vast experiences from numerous specialists and projects. However, it will be important to improve and update the manual continuously. Lessons learnt and new experiences need to be incorporated. Feedback is, thus, more than welcome.

Solar Heating in Cold Regions

by Jean-Frans Rozis and Alain Guinebault, ISBN 1-85339-329-0. Intermediate Technology Publications

This book is primarily aimed at technicians, architects and designers who are interested in solar heating systems in cold regions of developing countries where heating is an issue of utmost importance. It looks at how solar energy can be applied to improve conditions for poor people living in these regions. It is involved solely with space heating and does not look at the issues involved in solar cooking nor at photovoltaic systems. The book is divided into three parts: pan one examines the issues involved in solar heating; part two discusses particular solar elements which can be used in household and agricultural situations; part three looks at the physics involved in solar heating.

Part 1: The book opens with a brief outline of the types of solar energy available, followed by a description of the developing regions of the world where solar energy could have a major impact; the Andean Cordillera, the Himalayan chain and the Chinese plateau. The social and economic similarities of peoples living within these regions are highlighted.

Having discussed the problems caused by the lack of heating which these communities face, the benefits of using passive solar heating for houses, community buildings and agriculture are examined. The chapter ends with four case studies centred on the Moroccan Atlas, Sikkim (India), the Andahuaylas region (Peru) and Ladakh (India). Chapter 2 deals with enabling methodologies for solar projects.

Part 2: The second part of the book looks at specific solar elements; how they are constructed and how they work. Chapter 3 looks at living space and in particular at solar walls, trombe walls, attached greenhouses and a mixed hammansolar wall system used in a hospital in Ladakh.

Part 3: This is considerably more technical than the earlier chapters of the book. It discusses the factors affecting radiation: atmospheric conditions, thickness of atmosphere, angle of incidence etc., and how the quantity of radiation can be calculated. A very basic guide to heat transfer follows, which has good tables of thermal properties for appropriate materials. The next chapter deals with the absorption, collection, storage and distribution of heat energy, both indirectly through glass, and directly into large thermal masses. The role of thermal insulation is outlined in Chapter 8 for both glazed and opaque surfaces. The final two chapters combine all these ideas to discuss building design, choice of system and how to predict a building's thermal performance.

There are seven informative appendices which provide design details and graphs for solar greenhouses, henhouses and latent heat collectors and a method for economic analysis of benefits accrued through use of solar heating. The book is also published in French.

HEDON in action with World Health Organization July 1996

Report of 7th meeting. Geneva. July 1996. by Ian Grant

Since its first meeting in 1991 HEDON has been a forum for exchange of information between northern-based workers and organizations engaged in stove and household energy work for the developing world. At its general meeting it took a major step forward with plans for promoting and co-ordinating work within the very important field of reducing smoke pollution and its harmful effects on the health of women and children. Despite the well documented evidence of the serious damage caused, the major agencies and governments have shown little interest when compared with the extensive campaigns against cigarette smoking in Europe and the USA.

The meeting was attended by fifteen HEDON members from nine countries plus seven WHO professional staff members. Dr W. Kreisel, Executive Director Environmental Health Programme, WHO, opened the two-day meeting.

The main focus of the meeting was to agree and plan a programme of work which could be implemented by HEDON through its participating organizations. This would look at all aspects of the smoke health problem; from identification and measurement of sources and causes to possible interventions to alleviate indoor air pollution and reduce health effects. The following activities were agreed as important areas in which practical activities could take place:

· developing a set of criteria for assessing various aspects of household energy work. These would operate on four levels: technical, social, health and political;

· producing a new health criteria document on principles and methods to assess human exposure to biofuels;

· contributing a chapter to the forthcoming World Resources Institute report on Environment and Health;

· developing a framework to understanding more clearly the various ways in which changes impact on household energy patterns

· developing a small set of indicators related to household energy supply and use on a global level e.g. a national census could ask basic questions on types of domestic fuel etc.;

· compiling a document on the 'Healthy Kitchen' approach;

· establishing a list of currently available monitoring equipment, with its merits and faults;

· developing a list of the minimum number of variables required to gauge overall conditions in a community;

· promoting an understanding of the link between household energy and health through journals;

· identifying partners for cooperation to take the work forward, maximising future impact at field level.

A drafting committee, consisting of J. Sims, A. Klingshim and K. Prasad, with K.Smith as a consultant, was appointed to prepare a HEDON project proposal in time for the next meeting.

Technical Enquiries to ITDG

If you have any technical enquiries, ITDG's Technical Enquiry Unit (TEU) should be able to help you. ITDG has extensive contacts within the UK and Europe. and can respond on a wide variety of topics. If your enquiries are about stoves or household energy, then our stove team can also help.

Please send all enquiries to:

The Technical Enquiry Unit
Intermediate Technology
Myson House
Railway Terrace
CV21 3HT
Tel: +44 (0)1788 560631
Fax: +44 (0)1788 540270
Telex: 317466 ITDG G
(Please give your postal, as well as your email, address)

Back issues of Boiling Point

If you would like a copy of any back issues, please contact us. Multiple copies will be charged at œ2 per copy plus postage. A detailed index of all Boiling Point articles is also available, and will shortly be produced on disk.


Alternative Fuels


Safer and Less Smoky Stove


Kitchens, Pots and Cooking Practices


Stove Progress in Kenya and Sri Lanka


Muds, Clays and Metals for Stove Making


Fault Finding and Fixing


Stove Programmes in the 90s


Stoves Will Not Sell Themselves


Non-biomass Stoves


Stoves, Energy and the Environment


Other Uses for Stoves


Measures of Success


Solar Energy


Funding for Stove Programmes


Technology and Design Transfer


Women, Woodfuel, Work and Welfare


Biomass Combustion, Chimneys and Hoods


Household Energy Developments in Southern and East Africa


Sales and Subsidies


Clays for Stoves


Energy for the Household.


Household Energy Developments in Asia


Smoke Removal


How Much Can NGOs Achieve


Solar Energy in the Home


Household Energy in Emergency Situations

Editorial and Production Team

Ian Grant


Elizabeth Bates


Sandra Gibson

Administration Secretary

Steve Fisher

Head Office Technology Unit Manager

Alison Doig

Energy Project Team Leader

Smail Khennas

International Programme Manager

Agnes Klingshim

GTZ Representative

Cornelia Sepp

GTZ Editor

Ann Watts

Advisory Panel Member


M Abdelrazig, T Ahmad, G Ballard-Tremeer, N K Bansal, K Banskota, M S Bhandari, BB Gurung, H H Jawurek, B T Luvhimbi, B Pierre, H Polak, K Rijal, M Saleem, G U Sarhandi, P Simonis, P A Sopade, K M Sulpya, P Young.

Illustration on back cover: Matthew Whitton

Contributions to Boiling Point

Contributions are invited for the next two issues of Boiling Point, the themes of which will be:

· BP39: July 1997 Biomass fuels: their use and how different fuels affect technology choice. This edition will include charcoal and briquetting

· BP40: December 1997 Household energy. smoke and health. This edition will be mainly about the effects of smoke on health but contributions on how health can be affected by improved household energy provision would also be very valuable.

Contributions are welcome in the form of articles of not more than 1500 words in length. Drawings, photographs, graphs, and bar charts are all very welcome. Articles can be submitted as typescripts or on disc (preferably Wordperfect 5.1 or ASCII).

All correspondence should be addressed to Boiling Point, ITDG Energy Programme, Myson House, Railway Terrace, Rugby, CV21 3HT.

Enquiries and letters about Boiling Point can be sent by e-mail to <>

Boiling Point is the journal of the Intermediate Technology Development Group's Stove and Household Energy Programme (HEP) and the Household Energy Programme (HEP) of GTZ. It is printed by 'The Printworks', Rugby.

Opinions expressed in contributory articles are those of the authors and not necessarily those of ITDG or GTZ.

We no longer charge a subscription to Boiling Point but would welcome donations to cover the cost of production.

Helping stove workers

Intermediate Technology enables poor people in the Third World to develop and use technologies and methods which give them more control over their lives and which contribute to the long-term development of their communities.

Intermediate Technology is a British charity mainly funded by the Overseas Development Administration.

Intermediate Technology Development Group Ltd., Patron: HRH The Prince of Wales, KG, KT, GCB

Company Reg No. 971954, England. Reg. Charity No. 247257