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CLOSE THIS BOOKFuel Saving Cookstoves (GTZ, 1984, 128 p.)
3. Developing Stoves with Local People:
VIEW THE DOCUMENTThe role of the development worker

Fuel Saving Cookstoves (GTZ, 1984, 128 p.)

3. Developing Stoves with Local People:

The role of the development worker

How to approach the problem

An understanding of the broader issues of technology transfer can help clarify the development worker in introducing and promoting cookstoves. Without this understanding, a program can fail or have a lasting bad effect on the culture. Stoves can be totally rejected, along with any other innovation that comes from outside. Introduced technologies can lead to increased dependence on cities and imported goods, with a potential susceptibility to "technical fix" solutions that come with these dependencies. The example of solar cookers is a case in point.


Mass produced aluminum parabolic collectors were introduced as cookers in India in the 1950's [1]. Technically they operate well. They are durable and cheap. Early demonstrations showed that they would boil water or fry a hamburger. Much of the development was done in the USA, where aluminium is cheap and hamburgers are plentiful. It was assumed that they would solve firewood problems over great areas of the tropics, especially deforested regions where sunlight is abundant. These are the very areas most needing alternative cooking systems. Almost everywhere they were introduced' solar cookers have been a crashing failure. Reasons given are ingenious and credible: that the cook must stand in the hot sun to operate them; that they work best at midday, yet many tropical people eat in the morning and evening; that gazing into the mirror can make you blind; that through neglect the aluminum surface dulls. The fact remains that for some reason people generally didn't like them, or they would be used more widely. Worse, in parts of West Africa, for instance, there is general mistrust of new technology, because of the failure of solar cookers [2].

It is significant that solar cookers were developed in isolation from their potential users. The cooks were presented with a ready-made product in which they felt no involvement. Had local people been involved from the beginning in the development process, it might have been more successful for these reasons:

(a) People feel a pride of accomplishment in solving their own problems. The process of working out their own answers is part of the self-education that empowers people to deal responsibly with their own needs. If outsiders rob them of self-determination in techniques, unhealthy dependencies are created.

Where materials and energy are scarce, people are inventive. They have to be. No running down to the corner hardware store for every little gadget, you have to invent it. Technical design in poor countries can foster native ingenuity by crediting the people with intelligence and creativity, which isn't usually done.

(b) Local inventions work somewhat within the constraints of what can be locally manufactured. Local artisans and manufacturers will support only development of devices from which they themselves can profit. With local backing, cooker designs might have emerged to suit local production methods.

(c) The subtler needs of the people would have been incorporated, with all of the local variation that makes an artifact part of a culture - local symbolism and decoration and adaptations to local cooking.

(d) Maintenance is easier when only local materials are involved. The people have a familiarity with them; they know their materials' limitations and how to patch them up.

For example, the polished aluminum of solar cookers loses efficiency as it gathers dust and grease, yet users may not understand the need to keep them clean.

Our primary purpose in introducing improved cookstoves is to conserve fuel. But since the stove is so central to a family, its introduction can be an opportunity to help people take better charge of their own lives. This is especially important in countries that have suffered colonial rule (where decision making was often taken out of the hands of the local people), and in countries where a bureaucratic elite develops, following industrialized, consumer oriented patterns.

Often, though, village people feel that the "ethnology belongs to someone else, that it is being forced onto them from outside. Efforts should be focused on encouraging participation by villagers in any ways which may help promote local inventiveness. This will result in better stoves.

Especially in village cultures, people display ingenuity in solving their own problems. This has evolved as part of their way of life and should be fostered, watched for, listened to carefully and incorporated into the stoves' development whenever possible.

Fostering native ingenuity

One needs to develop ways to encourage local inventiveness, and learn how to solicit input from local individuals. Unfortunately, there are few examples of how to develop new techniques with local people. The Consumerist model of development (Fig. 3-1), prevalent in rich and industrialized countries, is often employed by development-workers, for want of a better alternative. The consumerist approach used by the marketing industry first generates a massproduced product, then persuades the public that they really want to buy it, often against their own good sense.

In many ways the consumerist model is inappropriate; more sensitive ways can be used which allow designs to evolve in response to the needs of individuals and cultures. This demands a totally different system, beginning not with the needs of industry but of the populace, ending with not a single product but a multiplicity of variable designs which continue to evolve, being constantly modified to meet the conditions which they must serve.

Throughout history, societies have slowly fashioned tools in response to gradual environmental and societal changes. We have developed a capacity to inventively solve our problems at a rate limited mainly by communications and the ways in which knowledge is dispersed.

Native ingenuity is present in every culture. Given normal rates of change we would expect cooking technology to develop in step with slowly decreasing fuel supplies.

In fact this has happened in many places. Almost everywhere, people cook using some kind of simple device to support the pot and contain the fire. Open fires using three rocks have developed into simple stoves, chiefly in two directions: toward the enclosed chimneyless rock and mud stoves of the tropics, and to the open hearth with chimney of medieval Europe.

Fig. 3-1 Consumerist Model


-Production is a single phase.
-Demand is generated by industry.
-Each product is separate linear process.

Given unlimited time in which to adapt, and without the confusion of outside dependencies, it is likely that people anywhere with fuel shortages would evolve "stoves" along these lines. But the firewood crisis has come so suddenly upon most people that designs have not had time to evolve and spread throughout the areas affected. The job of the stove development worker is to accelerate the natural rate of native ingenuity It is to help people design what in the course of time they might have invented anyhow.

In any one region it is likely that a variety of totally distinct stoves may be needed, to accommodate a wide range of cooking needs. By analogy, in transportation it is likely that in even a small area of a poor country several types of vehicles will be needed: heavy trucks, passenger cars, bicycles and buses all perform different functions. Similarly, the cooking needs of a street vendor, a housewife and a commercial baker suggest completely different stoves.

Figure 3-2 hints at a possibility of infinite numbers of designs, each one responding perfectly to the needs of one small area, perhaps a single village. Under this system, the people would feel involved, would recognize the worth of the product and could have the satisfaction of solving their own problems. However, this might take a long time. At current rate of deforestation, the fuel could disappear entirely in many countries before a solution emerges.

Fig. 3-2 Design by Evolution Model


-Production occurs throughout. Square boxes indicate production.
-Demand is generated by society.
-All products are interrelated.

Two opposite approaches have arisen in the development and supply of new technologies. For convenience let them be called the Grass Roots and Centralized approaches. The Centralized approach generally supports the Consumerist model; the Grass Roots approach is a product of Design by Evolution. A centralized system is not normally suitable for stove development; in fact stoves seem to be a product unusually well suited to decentralized development systems. (Paradoxically, dissemination may be most effective if it includes a centralized approach at national or regional levels.) The peculiar nature of the deforestation crisis indicates that some sort of combination approach will work out best.

Without advocating the wholesale adoption of either, here are the two systems laid out for comparison. Every circumstance will demand a different combination of the two approaches.

Grass roots development

that local people recognize their own needs and are capable of and interested in solving their problems, perhaps with a little technical help. (In places where strong dependency relationships are already developed, a grass roots approach assumes that peoples" interest in self-reliance can be revived.)

People are involved in generating their own solutions, feel ownership of the idea, understand its relevance to their lives and are likely to support it. A wider range of more suitable designs will result.


Can be slow - needing patience, a well-organized extension system and personnel with sensitivity to cultural issues.

Most suited to:

Rural poor in areas with traditional communication systems intact or good extension agencies. In cities: neighborhoods with close family or social organization. Suited to home production, small artisan workshops or custom on-site building.

Centralized development

Assumes: that outsiders know better than locals, that people should be forced into a new technology for their own good. Implies an already designed product, usually to be sold aggressively.

Sometimes fast. Able to reach many families quickly if they can afford it. People need no pre-education on the issues.

Alienation from decision-making sometimes means rejection of the product. Discriminates against the very poor. Perpetuates people's inability to inventively supply their own tools. Accelerates the capital drain from country to city and to industrialized foreign countries.

Most suited to:
Urban conditions in industrialized countries, richer people, sophisticated marketing systems; dense homogeneous populations, highly centralized social systems; mass production.

Note that neither system implies a political system. Nor are they exclusive of centralized policy planning, within which a Crass Roots approach can work, as in China.

What is the role of the development worker?

If people are capable of developing their own stoves, then what is the job of the outside development worker? Apart from accelerating native ingenuity, his/her role should be that of a newscarrier... "I saw this working in another country, perhaps you could adapt it to here..." who brings in new thoughts and experience. It is never to force people to accept new ideas, no matter how important they seem to be, but to expose them to a range of new alternatives. The worker should strive to become unnecessary, to not be missed when she/he leaves, because the locals will be taking full responsibility.

Assume you have chosen to work at a local level. An order of approach could be:

1. I'm here, I can do these sorts of things; if you have any problems maybe I can help.
2. I'm here. Do you have problems I can help with?
3. I see you have a problem. Can I help?
4. You clearly have a problem. Here are some solutions.
5. You definitely have problems. This is how you should solve them.
6. Solve your problem this way or action will be taken against you.
7. Your problem will be solved like this, however much you protest.

Usually it will be best to start with 1. If that fails, try 2. and so on. 6. and 7. should never be used; there are always alternatives. Here are three case studies to illustrate various levels of approach.

Lorena stoves in Guatemala

Lorena stoves were developed in highland Guatemala in 1976-7, initiated by a request from a peasant who was suffering from excess smoke in her kitchen. The primary development took place at Estacin Choqui in six months on a total budget of under $ 1000 for salaries, tools and materials. At the end of that time the stoves were working well enough that broadscale promotion could be started. Although they were mainly developed by foreign technicians, if there had not been critical input from locals (who usually get no credit for their effort) the program would almost certainly never have got off the ground.

The project was initiated by a peasant woman who had real problems. and knew what they were. When she saw a drawing of a stove in a visitor's notebook, she immediately recognized it as having value to her personally; "Is that a stove? Would it take smoke out of my kitchen? Can you build me one?"

The prototype never worked. It had been copied from stoves in India and the instructions were to build it of pure clay. Clay stoves crack badly unless they are really thin, so sand was added to the mix, first 30%, then 50%, finally in some cases up to 80%.

Once a non-cracking mix was established, the stoves needed refinement to suit local needs. The changes were of two separate types, physical and social. The physical changes were in general well thought out by the foreign developers. There were some exceptions when changes were made without taking the culture into account. The social changes on the other hand were dealt with badly until locals were involved.

First, some examples of physical developments:

In the Guatemalan highlands most of the population lives at 1500 to 3000 meters. Wood is scarce, so the poorest people supplement it with wastes such as bark, straw and corncobs, all of which burn really badly in open fires at high altitudes, due to lack of oxygen. The stoves, by enclosing the fire and directing the draft, make it possible to utilize these wastes.

Most families use several pots, cooking corn, beans, sauces and coffee for the same meal. They use several pots simultaneously, together with a wide earthenware hotplate for cooking tortillas, the mainstay of the diet. Any stove capable of utilizing waste heat from the first pot to cook or warm additional food will save fuel. Thus, Lorena stoves grew larger to accommodate the several pots used together.

Even with the physical problems partly solved, the stove needed adaptation to suit the local culture. Here is an example:

As cooking is usually done at ground level, several sociologists and knowledgeable friends suggested that we take care to conform with local custom and build stoves low to the ground.

"Demonstrations of these stoves were met with polite attention but without enthusiasm. Finally one woman scolded us: 'What kind of fools do you take us for? We know perfectly well how high a real cookstove is. Why are you building these insulting, floorlevel, undignified cookstoves?' Feeling rather foolish, we immediately began building stoves 75 - 90 cms (30-36 inches) high. They were instantly recognized by the women to be stoves worthy of the name and attracted

As Lorenas became more commonly used in the community, many adaptations were worked out by both the users and promoters, including for instance changing the metal can water heater for a ceramic jar because the metal rusts out over time. A list of these changes appears on page 93.

Early work on Lorenas slatted at about level 4 (You clearly have a problem. Here are some solutions.), see chart, page 37, then progressed to level 2 when it became clear that the people would not accept it at level 4. Had local people been closely involved from the beginning, instead of consulting only foreign "experts", stoves might have been bigger and higher from the outset.

Louga stoves in Senegal

In north and central Senegal many families normally cook outdoors on a single fire supporting only one pot. The commonest food is a boiled grain with sauce, both of which are cooked consecutively in the single pot. Fuel is mainly firewood, 1 to ½ meters long, with dung and some millet stalks used seasonally.

First attempts at a stove for rural Senegal copied Guatemalan Lorena types, but it was clear to the developers that these were merely variations of a stove developed for another culture far away. The Louga stove by contrast, was developed in a unique way, with villagers, in response to their own problems:

"They were already keenly aware of the amounts of wood they were using because of the energy survey being done in the village by the Peace Corps.

During an informal evening's discussion we brought up the increasing wood-scarcity. We all talked about that and women mentioned ways they used to reduce wood consumption: lids, windbreaks, putting embers out with sand. We talked about how fire heats a pot, where that heat goes, how it is lost around the sides of a fire, while making an analogy with the small lantern that was lighting the tiny hut where the fifteen of us were gathered.

The men and women said 'Yes, we lose a lot of heat around the sides of the fire.' Again they chatted about windbreaks, their problems.

At this point we passed around fired balls of lorena... 'Where did you get this?'... 'Where did it come from?'... 'Maybe we can make something with this.'

From there, they came up with the modified windbreak based on the ideas that:

1. Heat radiates in all directions from an open fire like light from a lantern.
2. Wind blows heat away.
3. A pot loses heat around its sides and top.

Basically what they came up with was a pot surrounded by lorena walls, a crude M3*... from their idea we suggested an entrance for wood and some technical points like spacing around the pot, thickness of walls. But it's their stove now." [4]

In some ways, development approached the ideal, levels 2 and 1 (chart, page 37), where local people were involved from the very beginning. However, dissemination of the Louga stove is now being set up at a national level. It is unfortunately still too soon to evaluate how well Louga-type stoves will spread, but initial acceptance has been enthusiastic.

This case should be compared with case studies of the Lorena and Nouna stoves, which both started will less local input.

Nouma stoves in Upper Volta

The Nouna stove was developed in Chad by a German volunteer who became aware that many women suffer from the smoke in their kitchens. As a model she used a stove she had seen in Europe as a child. She began working with a local mason to create a 2 hole stove with a long fire chamber and a chimney to allow the smoke to escape.

While the shape closely resembled the stoves of her childhood, she adapted the height to local cooking preferences and used adobe blocks and mud mortar, the most commonly available building materials.

When the volunteer was transferred to Nouna, Upper Volta, to work as a nurse, she continued her stove experiments on the side. She hired a local mason and taught him how to build the stove. A few women friends agreed to try it in their homes and found it to work well for local cooking needs. The word spread rapidly in the town, and she began to charge a fee for materials and construction. This became espcially important after she and the mason decided to substitute fired bricks, mortar and concrete for the adobe, to make a stronger and more durable stove.

So far the approach had been at level 4 (chart, page 37). She was promoting the stoves, using friends and acquaintances as avenues of publicity. Her success in the town is not only due to the fact that the stoves were seen as an improvement on traditional cooking methods, but also that she had become respected and well known for the work she had been doing as a nurse.

By 1978 a German development agency began funding the project. A demonstration center has been built in the capital, and publicity campaigns have been started in the media.

Three or four different models, differently priced, were available by Spring 1980. Customers chose stoves at the demonstration center and had them built in their homes by a team of masons. Relations with the national government and international aid organizations were good; in fact many of the customers were government employees and their wives. Over 1000 stoves had been constructed in Upper Volta by mid 1980. The project had established itself at level 5.

- There is little flexibility to accommodate individual needs. Stove masons have become "experts" who sometimes assume they know better than the cook what she really needs.

- Most local people are not building their own stoves because construction relies on imported or scarce materials such as brick or cement. This periodically raises the price of stoves and draws capital out of the area.

- The cheaper original adobe; models are not currently being built, which discriminates against poor people.

- There is limited opportunity for feedback from users, and no provisions for including such information in future stove designs.

Unless parallel models and new ways of development and dissemination are instituted, the limited market for Nouna stoves will have been saturated long before a significant reduction in wood comsumption is achieved.

Stove development: Where and when to start

There is always a temptation to try to solve problems from a comfortable vantage point for thinking out answers: your desk, the air-conditioned office, your home. All of these will be distant from the problem. The capital city is usually not representative of the country in general. However tempting it might be to work in comfort, try to go where the problems are immediate, in villages and the big urban squatter settlements, and live with the people you are working with.

Wherever you are working, first. assess what you do best that will be helpful there; it may have nothing to do with stoves, but it will help you to gain trust and respect, and to establish yourself as a person with something to offer. Only when you have the respect of the community can you expect them to take ideas seriously.

Where? Any stove development program should begin not only where the need is greatest, but where it stands the highest possible chance of success. Any of these factors will help - start where:

- fuel supplies are rapidly and dramatically diminishing,
- people are open to new ideas,
- there have been successful introductions of other simple technologies, and few failures,
- the people have enthusiasm and enough time to make, or enough money to buy their own stoves; if people are without hope the scheme may fail,
- rapport is good between the community and a well-respected woman extension worker,
- men and women are used to working together; in most places men are the builders and women the cooks, so cooperative efforts will be needed.

When? The dry season is the best time to start, especially immediately following the harvest, when people have plenty of free time. Roads are in good condition and travel is easier. For mud or sand/clay stoves, drying would be fastest in the dry season.

Developing prototypes with local people

In order to develop a prototype model, ideally you would first build on knowledge and skills people already have. Your second move is to sit down with the cooks and solicit their ideas. Third, you may want to build a locally-responsive stove in a less visible place until you have a model you can comfortably put on public display.

1. Wherever possible, build on techniques people already have. Search out local stoves and other tricks for conserving fuel. These could include wind-shields, devices for stabilizing pots such as metal tripods, and terra cotta fire containers. In the Sahel, women douse the embers with sand, using the charcoal created to cook later meals; in Northern India, small children are delegated the tedious task of continuously feeding the fire with tiny twigs; Guatemalans build racks over the stove for drying firewood. In certain areas, stoves in some form may already exist.

By emphasizing the gains already made, you can focus on the fuel question, give credit for local inventiveness and prepare people to take the next step. If there are local stoves of any kind, they are probably well adapted to local conditions, though it may be easy to make simple improvements. Explain your logic carefully so that people understand the reasons for the changes. Often this will spark ideas from the people themselves, which may emerge as cautious suggestions, or more likely in modifications of stoves they build. Poor people in developing countries are accustomed to having their ideas devalued by outsiders, so be sensitive to innuendos and subtle hints which they may express without force or conviction. Development workers and technical specialists, however good their intentions, often fail by not knowing how to listen to the ideas of humble folks. The peasant may feel overawed by strangers, be uncomfortable with an unfamiliar language, or be conditioned to believe that as a person without formal schooling he or she has no worthwhile contribution to make.

Although in your own experience they may seem irrelevant, be especially. careful to consider seriously even the most unlikely suggestions. The life experience of folks from totally different backgrounds enables them to notice things you will certainly miss. In this way, between you, new ways of solving problems will emerge which would be unattainable to either of you in isolation.

2. If there are no native stoves on which to improve, sit down informally and spend time discussing the fuel situation with cooks or whoever has to provide the fuel. Encourage solutions which people may already have thought out, things they have seen in other places... "Once when I went to Oaxaca to the market there was a woman cooking tortillas on a little metal box..." You could encourage them to try out their own ideas: "Why don't you build one? We could use it for the big fiesta on Sunday, but it might work better at this altitude if you build the place for the fire a bit bigger..." Alternatively you can offer your own experience, telling stories from other places; travellers tales are usually popular... "I saw people in China with a stove built of earth that worked really well..." Or, "A teacher in my own country told me that you use much less wood if you keep the lid on the pot". The Louga stove was developed in a Senegalese village in this way.

The conversation may open up ideas of other ways to solve the problem, changing your own fixed notion of a stove that would improve things. Villagers may see solutions in terms of planting more firewood species, stopping forest fires, switching to more uncooked foods, cooperative cooking or insulation of pan lids. Be open to their ideas, they may be right. In Nepal for instance, the terrible erosion caused by firewood collection is now so bad that a good case can be made for subsidizing cheap efficient kerosene stoves and using foreign aid to temporarily cut the price of kerosene. The price of kerosene could then be allowed to gradually rise, as firewood plantations began producing. This was suggested by a Nepalese peasant as a stopgap measure to allow the new firewood plantations to take hold. Although on first sight this is a questionable suggestion, seen from his viewpoint it makes a lot of sense.

As ideas start to solidify, try making small models of the kinds of stoves you are discussing, out of clay, paper or thin metal. Limit your suggestions - remember that each idea that comes from the people themselves is probably worth several of yours.

Finally, if there are already specimen stoves in your area, go with people to see them. Most people love an outing; they will then be able to discuss something tangible.

When ideas seem concrete enough, offer help in building a prototype. Try to involve as many people's ideas as possible when you work with them on developing their prototype stove. (Be careful, your assistance will be better respected if you already have experience. Spend a few days working alone with the materials to gain some insight.)

Do some simple fuel conservation tests with people to make sure it really does save wood; use your experience 'to suggest whether there might be more economical ways of using it (see Chapter 6).

3. If working directly with local people is impossible, a third and less desirable tactic is to develop a locally-responsive stove away from public view, with help from selected locals. This could be in the backyard of your house, in a school or experimental facility. The Lorena stove was developed very much this way. One advantage of this method is that you can make mistakes on prototypes without becoming a laughing stock and losing credibility for the whole project.

You could try either to evolve a design yourself from your understanding of the problem, or to take a recipe-book approach, modifying a design already proven elsewhere. If you build from a set of instructions, follow them closely the first time to become accustomed to the technique, then try modifications to suit local conditions.

Beware of using unmodified designs from other places. They may be effective within a single culture, for instance within a group of villages in the same region, or in several large cities which have close similarities. Yet it is highly unlikely, for instance, that an unmodified design from rural Guatemala would be appropriate in an Asian city.

Here are some criteria for design. You will certainly want to add your own; use them as a basic list.

- Design only things which can be locally produced either by householders or by artisans, using existing local skills.
- They should be built chiefly of local materials to prevent capital flowing out of the immediate community, and to cut down on transport difficulties.
- Materials should cost as little as possible.
- Construction should require no special tools or difficult techniques (though local people may have a wide range of unexpected skills; look around).
- Stoves should be designed so that it is impossible to use them in a way that consumes more fuel than an open fire.
- Rather than a single fixed design, there should be a set of principles which householders can use to choose a stove that suits their specific needs.

Beware of your own preconceptions of what a stove should look like. You are designing a method for using less fuel.

It is essential to involve local expertise; ask a nearby friend/cook to work with you and criticize. Encourage selected people to visit, particularly masons and metalworkers, to see whether they anticipate construction problems. If local artisans in related fields are available, ask them to work with you. You may have to pay them, or they may be enthused enough about the stove to volunteer.

Try to have it working when visitors come; encourage people to cook on it - a cold stove is difficult for anyone to assess. Later, when you are satisfied with it, ask whoever cooks for you to spend a week using it or hire local women to cook on it. During early work on Lorena stoves local women were paid to spend several days cooking all of their family's meals on a whole range of different models. They were observed and asked to be openly critical of performance.

Refinements through checkups

Conventional marketing theory suggests that consumers are on their own once the product is paid for. Unless replacements can be made of either the whole product or defective parts, there is no profit seen in following the product into the user's home. In contrast, the Design by Evolution model (Fig. 3-2) demands that a close relationship develop between "designer" and "user", to the point where it is not always possible to decide which is which. Further refinements of the design will come chiefly from users, if only because there are so many more of them than there are designers. The designer becomes much more a coordinator, collecting innovations and refinements and redistributing the ideas to whoever can make use of them.

Reinforcement using straw, pine needles, steel bars;

Concrete reinforcing at the edges most likely to break; Various unlikely shapes, including the Joyabaj 3-tunnel and L-shape


In Guatemala, the Lorena stove in the first two years of promotion spawned a great number of adaptations. Here are a few which have gained widespread acceptance:

Observations of stove use by follow-up teams also revealed defects which owners had found ways of circumventing; for instance, they found that on cold nights users would remove the front damper door to warm themselves: "... removing the firebox door in order to feel the warmth of the fire may detract from fuel savings, yet it may be just this adaptation which preserves the cooking place as the central gathering place in the Indian household." [5]

Checkups on stoves in use are as important in urban as in rural conditions though sometimes more difficult, particularly in the case of manufactured units sold through markets. In both country and city, investigators should look for:

- modifications and adaptations of the physical form of the stove which could be fed back to manufacturers,
- unanticipated uses which could be pointed out to other uses,
- defects needing to be redesigned,
- fuel saving tricks to be circulated among other users,
- verification that each stove does in fact save fuel; users can be taught simple ways to check on fuel consumption (see Chapter 6).

Two phases of follow-up will do different things (see also Evaluation and follow-up, Chapter 4).

1 month checkup: chiefly to assist the cook with any difficulties, but also to spot design faults.

6 month checkup: will be more useful to design modifications. The monitor can carry news of new ideas (a special cake recipe is always popular) and fuel-saving ideas. At this time look for second generation stoves, i.e., copies of the original made by neighbors, and assess what changes have been made. Are the changes beneficial or do they defeat the purpose of the whole thing?

In addition to field visits, there should be an accessible center or person who can be consulted by stove users and to whom they can make comments, complaints and suggestions for improvements in product and teaching (see Setting up stove centers, Chapter 4). The stove that broke a tooth.

The importance of follow-up work and involving native people is exemplified by our first documented failure!

It occurred in Guatemala when we gave the first Lorena stove course away from the experimental station (Estacion Experimental Choqui, now called ICADA). The village of Patzicia had been destroyed by the 1976 earthquake. Two of us went there and we were received with enthusiasm and respect. Though the course had only twelve official participants, more than 200 people watched. The course ran extremely well. Two stoves were completed, both meticulously finished, giving them a polished marble-like appearance. Ceremoniously we lit small fires in each stove to demonstrate how they worked. The crowd was astonished to see smoke coming out the chimney. The townspeople seemed enthusiastic.

Six months later I returned to the village as planned. The family in whose home I had stayed during the stove course invited me to lunch. While waiting I browsed through the village. To my dismay I discovered that the two stoves built six months earlier had been destroyed, and not a single new stove had been built.

During lunch not a word was mentioned about stoves. I suspected the topic was being avoided out of respect for me as a visitor send a foreigner. As I prepared to leave I casually asked, "What happened to the stoves?" Their response was evasive - they had destroyed the stoves to make room for a new kitchen in which to build a new stove. That did not sound true. Something had happened to cause them to reject the stoves. What?

I was sensitive to their politeness. (Part of the culture is unwillingness to disappoint or insult a guest.) But I could not leave without some answers.

Instead of catching the first bus home I walked through the village out into the countryside. There I met a middle-aged man returning from the fields. As we talked the subject turned to cooking. He had heard about the stoves. "They are no good," he, said. "They make tortillas with pebbles in them. Don Panteleon broke his tooth eating a tortilla made on the stove. It breaks teeth."

Now I knew why the stoves were rejected. But what had gone wrong?

The stoves require soil which contains a clay that fires. The soil around the village was a rich loam - high in silt with very little clay. Had we involved villagers in the project, we would have first talked with the local people about the quality of the area's soil. The village people knew their soil was not good for making clay bricks, that it would not fire. In the cooking process, pieces of the stove around the pot had crumbled into the food. These were the troublesome stones.

The experience with the stove that broke a tooth taught us two valuable lessons. The first was to involve local people in choosing materials and developing the stove for their village. The second was the importance of follow-up. Had I not returned, we might have continued the same error in other communities.