|Solar Cookers in the Third World (GTZ, 1990, 228 p.)|
|3. Conditions of Acceptance for Solar Cookers|
Over the centuries, stoves have become accommodated to the eating and cooking habits of their users - and vice versa. For solar cookers, there is no getting around a comparison with traditional stoves.
Types of stoves: The most common type of "stove" is an open fire, sometimes supplemented by other cooking facilites. Some examples:
- Kenya: Kenyan stoves are appropriate to the climatic, economic and cultural situation. Most women do their cooking over a three-stone fire like the one shown in figure 16. Those who can afford one use a little round wood/charcoalfueled sheetmetal stove called a jiko. Some Nomads build little baked-clay (adobe) walls around an open fire, and others cook in a kind of adobe pit. For Nomads and for market women, mobility is a prime criterion for a hearth/stove. In areas with pronounced seasonal changes in temperature, mobile stoves are also prefered, since they enable cooking indoors or outdoors, as desired. In cool weather, the hearth also serves as a heater. Many families also use it as a source of light, making it the centerpoint of social life.
- Pakistan: The cooking facilities used by Pakistani families also differ according to region and family income. Most rural housewives cook their meals on one or more chimneyless adobe stoves. In families with adequate income, the women cook on a gas- or kerosene-fueled metal stove. Practically every rural Pakistani family has its own oven for baking, in contrast to Indian families, who frequently bake their bread on top of the adobe stove. The oven also serves to keep the food or tea water warm for extended periods. At higher elevations and in other relatively cool areas, the hearth also serves as a source of heat, but rarely as a source of light or as a family meeting place. Afghan refugees in Pakistan cook on an open three-stone hearth (indoors in winter and outdoors in summer) or on a self-constructed horseshoe-shaped adobe stove. Some families also have a metal stove or kerosene cooker. Most refugees are given a free kerosene cooker. Unfortunately, the cookers in question are of poor quality, smoky and bad for the taste of the food. Consequently, some families hardly use their cooker at all, or even buy a better one at the market. Women use the cookers mainly for boiling water for tea and for preparing light dishes, e.g. vegetables.
- India: A small chimneyless earthen or brick stove called a chulha is the customary cooking device among Indian women. A given family can have either several earthen stoves for one pot each or one big chulha for several pots at once. Small, charcoal-fueled metal stoves that double as space heaters are also used in cooler regions.
- Mali: Most Malian women cook on three-stone hearths. Additionally, there are various types of earthen stoves for one or more pots, plus various metal/cast-iron cookers. The women often use several cookers at once if necessary. Nearly all Malian hearths are portable and can therefore be used indoors or outdoors, depending on the weather and lighting conditions. In hot areas, the women prefer to cook indoors to avoid the high outdoor temperatures. In cooler areas, the hearth also serves as a space heater. In the evening hours, the open fire becomes an important source of light and a meeting place for family members and neighbours.
- The Sudan: Three-stone hearths are customary in rural areas. They are often accompanied by tin stoves for charcoal. Also customary are baking tins over a wood fire (cf. Fig. 17). As a rule, a family has several different lightweight hearths.
Side effects: The main lesson to be drawn from the above examples is that traditional hearths can be quite versatile and have some positive side effects, e.g.:
- versatility: traditional hearths are more than just means of
cooking food; they also provide heat and light;
- side effects: preservation of food by smoke from an open fire increases storability and, hence, makes for a safer supply of food; the smoke also drives away insects;
- communication center: in many societies, hearths have an important social function in that they serve as centers of communication, especially in the evening;
- conclusions: solar cookers have to compete with those merits. The extent to which they can or cannot compete depends on criteria like the following:
Size of hearth: Sometimes, setting up and operating a solar cooker takes a considerable amount of (extra) space that is not always available, especially in densely populated urban quarters. Some solar cookers - especially reflector cookers are quite voluminous and require an accordingly large area.
Setting up: While some solar cookers are installed for stationary operation, others have to be set up anew every morning. Many Indian families that own an ATRC cooker, for example, complain that it is too heavy to be carried in and out of the house every time it is needed for cooking. The solar cooker project that was carried out among Afghan refugees showed that many would simply use their traditional hearths if no one was around to help carry out the box in the morning. Many devices are just plain too heavy for women. Others, like the one used in the North Horr, Kenya Project - are too bulky for easy transportation. Mobility is particularly important for some socia1 groups: polygamous women, market women, field workers. Accordingly, solar cookers must satisfy quite stringent demands with regard to mobility.
Stability: Sometimes, mobility conflicts with the stability that is needed for, say, stirring the food, keeping the cooker from being knocked over by children or domestic animals, etc.
Cooking height: Coming home from a long, hard day out in the fields, women in the Third World prefer to sit down or squat for cooking. Some solar cookers, however, can only be operated standing up; in some cookers, the pot is suspended at shoulder level. That, too, impairs their social acceptance.
Location: Women customarily do their indoors cooking in a walled-off cooking area or in a separate room or hut. For some Nomads in northern Kenya, it is strictly taboo to cook or eat outdoors. According to one adage, "only hyenas eat outdoors". But it lies in the nature of (most) solar cookers that they be used outdoors, no matter how disdainful that may be in Kenya. It is also frowned upon in India, not only because a stove standing outside is easier to steal, but also because proper weather protection is hard to come by: the stationary IGDP-type cooker (Dhauladhar solar cooker) in India has to be covered with a tarpaulin and carefully serviced during the rainy season. Very few solar cookers, e.g. the cooking part of the Solar Hot Plate Cooker, can be used indoors.
Cooking in the shade: As a rule, the solar cooker has to stand out in the sunshine, while the woman doing the cooking normally would prefer to be either indoors or at least outside in the shade of a tree, where there is also room for chatting with other women and the children. A reflector cooker, however, is merciless: the woman is forced to stand out in the sun, because the cooker has to be kept properly adjusted, and the food has to be stirred periodically. Only few solar-cooking devices will allow the work in the shade, e.g. the heat-accumulating ISE solar cooker, the Solar Hot Plate Cooker, the Convective Solar Cooker, etc.
Cooking capacity: The question of how well the amount of food that can be cooked at once in a solar cooker, will meet the requirements of an average target-group family is an important criterion for acceptance. The aforementioned eating habits play an important role with respect to individual family members and social groups. Solar cookers in North Horr, Kenya, are too small for most rural families, because their cooking capacity is limited to three kilograms. Large families in India have the same problem with ATRC cookers. In many projects, the capacity of the cooker seems to be oriented more along the lines of a four-member urban family than for a typically large (10-15 people) rural family.
Loading capacity: Several vessels may have to be used at once, depending on the complexity of the individual dishes and how many steps of cooking are necessary to complete the meal. Using more than one big pot at a time is practically impossible with a reflector cooker. Considering the variety of dietary patterns, heating and eating and cooking habits and the number of people who may wish to eat together it is no wonder that solar cookers are widely regarded as too small. A good solar cooker should have adequate loading capacity in addition to some extra "holding space'' for pots, pans and dishes.
Type of vessel: Kenyan and Malian women use different sized pots made of clay or aluminum. Aluminum pots are also the rule in Pakistan. If solar cookers will accommodate the customary vessels - instead of only pots with particularly flat bottoms (as they are necessary for the Stoy/Pohlmann cooker), they will find a higher degree of acceptance.
Cleaning: Some solar cookers seem to be difficult to keep clean, e.g. after a pot has boiled over or spilled. For example, the Sobako cooker used in Kenya had to be partially dismantled for cleaning. Conversely, solar cookers that can be kept clean by wiping with a moist cloth are naturally more acceptable. Cleaning always comprises the danger of damaging the reflecting/absorbing surfaces. Here, too, solar cookers have to compete with conventional devices that are either easy to keep clean or rarely require cleaning.
Versatility: Box-type solar cookers and solar steam cookers are unsuitable for roasting and grilling and only conditionally suitable for baking. In fact, genuine versatility in the sense of being suitable for cooking, roasting, baking, frying, etc. is displayed by very few solar cookers - meaning that they are only capable of assuming certain limited functions in connection with the preparation of food.
Useful time: With the notable exception of the usually quite expensive and complicated heat-accumulating devices, solar cookers are only useful during certain hours of the day and seasons of the year, in addition to needing good weather.
Substitution of traditional cooking facilities: Many of the above considerations document the fact that solar cookers can rarely do more than supplement the existing cooking options, i.e. they cannot replace the traditional cooking facilities. Such was the case in India's solar cooker project in Gujarat. Traditional and solar-powered stoves/cookers are almost invariably used simultaneously, e.g. with the solar cooker serving to heat the food up, and the wood fire doing the rest of the cooking. As long as the traditional cooking facilities are also regarded as a source of heat an light, solar cookers can only be a supplement, never a substitute.