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close this book Boiling Point No. 31 - August 1993
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GTZ News

Co-ordination & Advisory Centre for Integrated Household Energy Supply (IHV), P O Box 5180, 6236 Eschborn, Germany, Tel: 6196 793004-7, Fax: 797325

Editor: E. Metzen

How To Improve A 2000-year Old Technology

by Naceur Hammami, National Energy Agency of Tunisia and Dirk Ullerich, GTZ/Special Energy Programme, Tunisia

The use of a domestic oven for bread baking has been common in Tunisia since 150 BC, the time of the Phoenicians. The traditional family-sized oven is known in Tunisia as "Tabouna" or "Gouja". It is a vertical oven made of burnt clay. It is similar to traditional oven types, "Tandoor" known in Jemen and Pakistan.

The Tunisian baking oven is heated at least once a day with fuelwood, branches or dried dung. To keep its inner layer clean (ie. to burn off all soot particles) it is necessary to heat the oven up to at least 500C before the dough is stuck to the oven wall. This heating-up procedure consumes an enormous amount of energy because the top of the oven remains open. An analysis of the energy situation in rural North West Tunisia confirmed that households use most energy for baking bread. Besides the "tabouna" bread, seasonally another kind of bread, "tajine bread", is baked in ceramic pans over the 3-stone fire.

Promoting Energy Switching

The strategy for improving this energy situation gave priority to an energy switch from biomass to lp gas or kerosene for bread baking. Both types of fuel are widely available and already used for cooking and lighting. Tests were conducted with gas ovens imported from Morocco for baking tabouna-like bread. Metal pans were introduced to eventually replace the ceramic pans so that Tajine bread could be prepared by using a gas burner.

Gas ovens have been installed by the project in remote areas since October 1992. A first follow-tip showed positive results, so that now the possibilities for local production of these ovens are being studied. The metal pans to prepare tajine bread enjoy high appreciation among women. However, the fuel substitution effect remains limited if enough biomass is locally available. It also takes more time to bake the same amount of bread because the metal pans have a smaller diameter than the traditional ceramic pans.

Rational Use of Biomass

Tabouna bread is a staple food of the rural population. It is therefore assumed that people would be unlikely to give up eating this bread prepared in the traditional tabouna oven. The alternative was to improve the energy consumption of such traditional ovens. A lid was developed to keep more heat inside during the heating-up phase while at the same time allowing the smoke to pass. After the dough is put into the oven the lid closes the oven opening completely.

The lids save about 50% of biomass under workshop conditions. If combined with improvements in fire management (ie. chopped wood and feeding the oven continuously) they could even save up to 75% of biomass energy.

The laboratory tests were followed by a one year field test with selected households participating. This field test was also an initiative for commercial distribution and was therefore based on the local production of the lids in towns or villages of the area.

Promoting the Lid

The selling campaign turned out to be rather time and cost consuming. Door to door selling was necessary for two reasons: traditionally Tunisian women don't leave their house and a high percentage of the population lives in scattered dwellings. Due to rain and snowfall the area could only be reached by one small promotion group during winter. Despite these and other limiting factors almost 400 households bought and use the oven lid. Given a choice, the vast majority of the households preferred a more expensive version of the lid.

A monitoring survey carried out some weeks after the selling, showed that most women observed other improvements caused by the lid such as a better quality of bread, better heat conservation so that water and meals could be heated up on the embers after bread baking.

Moreover, they noted less smoke and a better fire protection of the house. The better version of the lid in general attracted the husband's interest more easily. This is an important factor since it is usually the husband who makes the final decision on a purchase.

Commercialisation Strategy of FECT by Thomas Neumaier and Rahmat Jan, Fuel

Efficient Cooking Technologies Project (FECT), Pakistan

When FECT started its activities in 1990 one of its objectives was to establish a self-sustainable dissemination system of improved devices, here the Multipot Stove (MPS) for Pakistani beneficiaries. Then the project still followed the strategy of its predecessor, the Domestic Energy Saving Project, serving Afghan refugees since 1984.

The former dissemination strategy Afghan producers made the MPS while the project purchased them from the producers and transported them to the villages where they were sold. The MPS were sold in village shops, and the shopkeeper was restricted to sell at a fixed price. In addition the MPS was sold door to door by a local man and woman hired on a monthly basis by the project.

With this dissemination strategy the project had to take over the following costs:

- credit to producers in cash or kind;

- transportation from producer to project store and from project store to village shops/custodies;

- commission for shop keepers;

- salary for local sales couple;

- commission on the selling of MPS from the custody;

- large exhibitions and promotion campaigns;

- project sales force.

It was believed that handing over the MPS production to Pakistani producers would automatically

promote independent production using the existing channels of Pakistani commerce. However, although the Pakistani producers were financially supported and trained they could not compete with the Afghan producers. Afghanis had lower profit margins for lack of alternative income generating activities. They usually produced in remote places far away from markets keeping their production costs low, and relied on the project picking up their MPS. Their experience gained when working for the Domestic Energy project enabled them to produce better quality products than their Pakistani competitors.

Commercialization stages of MPS

In mid 1991 the FECT project decided to move determinedly towards a commercialization of MPS production and dissemination:

Step 1: stopping the production of Afghan producers

For several reasons the involvement of Afghan producers became counterproductive in the attempt of FECT to reach self-sustainability. It was believed that MPS production would collapse when Afghan producers returned to their own country. Their production sites were usually far off reach of any wholesalers, shop keepers or transport companies. Therefore, the production of Afghan producers was completely stopped.

Step 2: stopping door to door selling

Door to door selling was very costly to the project and annoyed the village shop keepers because it was unwanted competition to their own effort to sell MPS. It could also not be expected that the sales activities of local family business would ever become self-sustainable.

Step 3: withdrawing price restrictions

Formerly, the producers were restricted to using methods fixed by the project. Since there was not sufficient profit they were reluctant to produce MPS. The project released this restriction and supported producers who could produce within an acceptable price range.

Step 4: identification of appropriate producers

It was feared that promotion campaigns would be ineffective if demand were created in rural communities but enough stoves were not available. An increase in the number of producers was necessary and would also create competition leading to optimal pricing and qualitv standards The most appropriate new producers seemed to be the producers of traditional, metal stoves to be found in each large town. These people have already established contacts with wholesalers and retailers interested in stoves and so were encouraged to include MPS in their production. An attempt was also made to encourage the establishment of new stove producers provided they were ready to set up their own distribution channels.

Step 5: identification of appropriate dealers

Local shops - HATTI - were found not to be appropriate for MPS sales. They were too small to stock items like MPS and they bought their goods from bigger shops in towns rather than wholesalers. Shops selling traditional metal stoves and hardware turned out to be the most suitable for MPS sales.

Production and marketing of such products usually take place in the same locality. Producers in remote areas always had a wholesale shop in the main sales centres or bazaars. It was decided to give emphasis to these centres and their producers/ wholesalers for promotion activities.

Impact of Commercialization Strategy

Until the middle of 1991, 9860 subsidized MPS were disseminated bv independent Pakistani pro

ducers. With the subsequent appropriate commercial approach , 25,000 MPS were disseminated without credit support. The project provided only training, production checking and promotion and marketing advice. The women stove users need to be made aware of how to operate the stove efficiently but this is difficult because it usually Pakistani men who buy the stoves.

Step 6: appropriate promotion

The traditional transportation channels and business norms in which the kitchen or hardware shopkeepers transport and sell their items was named as natural distribution channels. The project tried to promote to reach the end users, dealers, producers and wholesalers who lived within these natural distribution channels. Stove companies were also advised to integrate themselves in these channels. Exhibitions were held in villages in an informal way whereby villagers were encouraged to discuss the problems of deforestation. MPS retailers were invited to put up stalls selling the product. Retailers and producers/wholesalers were brought together that way. The type of promotion material was selected with the consultation of producers and retailers and was so distributed in an effective way.

Impact of commercialization strategy

Until middle of 1991, no independent Pakistani producer continued his production when the project still followed the former dissemination strategy. When the commercialization strategy was initiated 10 Pakistani producers in North West Frontier Province and Punjab started an independent production of the MPS. No credit was given to them neither in cash nor kind. The project only trained them, checked their production intensively during the first days and supported them in promotion and identified sale outlets for them.

The projects dissemination records show that 9.860 MPS could be disseminated when applying the former project subsidized dissemination approach. Applying the new commercialized approach resulted in 24.997 MPS disseminated.

Follow-up surveys showed that best results from the MPS could be achieved where women are fully aware of the operation techniques of the stoves.

However, the active integration of women so far seems to be a problem since the actual buyer of stoves are usually men who do not use the item. Based on the experience made during the first phase of the commercialization approach the promotion strategy will be improved and project stoves further developed until they are sufficiently acceptable to the female users and can be successfully disseminated in a self-sustainable way.

Stoves Impact On Environment

from a summary of an Environmental Impact Assessment conducted on behalf of GTZ/IHV Project by Ms. Brigitte Fischedick, Environmental Concept Ltd. Berlin

It is often assumed that improved stoves have a positive impact on the overall environment. In a recent desk study Ms Fischedick analysed such effects of improved metal stoves comparing the Teliman stove/Mali and the Mai Sauki stove/Niger with their traditional predecessors. In ha study the author looks at the complete life cycle of a stove including production, transport, period of usage and material leftover after usage.

Models of Stoves Analysed





3-stone fire

foyer malgache (old metal sheet)



Mai Sauki (old metal sheet)


Teliman (new metal sheet)

Mai Sauki (new metal sheet)

Present models of the improved stoves are produced from old sheet metal (OS). However, the use of new sheet metal (NS) imported from Europe has been considered for there is a trend to replace metal barrels from which old metal sheet is taken with plastic barrels from which old metal sheet is taken with plastic barrels. Overall there was no big difference of environmental effects - apart from water pollution - between stoves made of old or new metal sheet. If imported new metal sheet was considered the environmental costs for metal and sheet production as well as for transport to Mali and Niger are included in the. calculations. Savings, conservation and reductions are expressed in comparison to the respective traditional stove models.

Energy Saving per stove per year.

by reduction in fuelwood consumption and saving in energy for transport of wood


OS 8.894 x 103 MJ


NS 8.840 x 103 MJ

Mai Sauki/Niger

OS 2.584 x 103 MJ

Mai Sauki/Niger

NS 2.570 x 103 MJ

Potential energy savings under environmental aspects are not really influenced by using either old or new metal sheet.

Conserving forest area

Around 80% of cut wood in Bamako and Niamey is used as fuelwood. It can therefore be assumed that a reduction of wood consumption leads to direct conservation of forest area. Each improved stove could help to conserve 0.05 ha forest area in Bamako and 0.015 ha in Niamey. These figures are the results of a theoretical calculation. Unfortunately, data are not available to verify this result. It is however, noted that also dead wood is sold on the fuelwood markets in both cities. The consumption of dead wood has no conserving effect on forest area.

Reducing emissions

Saving energy through improved stove reduced emissions into the atmosphere. The following figures show such reductions of emissions per stove per year.

One Teliman reduces CO2 emission by nearly 1 ton per year, one Mai Sauki by 0.25 tons. 20,000 stoves disseminated so far reduce CO2 emission by 25,000 tons per year. If compared to the CO2 emission of Germany of 1 billion tons per year these reductions seem rather marginal. However,

Niamey and Bamako are only two African cities where even more improved stoves could be disseminated. Therefore the overall potential of improved stoves to reduce CO2 emission is much higher. The reduction of emissions is not considerably influenced regardless if using either old

or new metal sheet for stove production.

See Emissions table below.

Water Pollution

The production of new metal sheet for one Teliman would require 228 litre of water and would release 3g of oil, phenole and tar into the water circle. The production of additional new metal sheet for one Mai Sauki requires 60 litre of water and releases 0.8g of above chemicals.


The production of new metal sheet in Europe for one Teliman results in 1.5 kg of solid waste that needs to be deposited (0.4 kg for one Mai Sauki). After an improved stove is worn out one Teliman leaves 6 kg metal waste behind, one Mai Sauki 1.57 kg. Data on actual or potential ways of recycling this waste are not available.

Reduction in Emissions in kg per year


Teliman Mai


Carbon dioxide



Carbon monoxide






Total Suspended Particulates



If you would like more information on this article, please contact Ms Fischedick, Environmental Concept, Ebereschenalle No. 6, 14050 Berlin.