|Solar Cookers in the Third World (GTZ, 1990, 228 p.)|
|3. Conditions of Acceptance for Solar Cookers|
Essentially indirect impacts, effects, side effects, aftereffects and consequential effects are sometimes accentuated in an attempt to justify solar cooker projects.
Saving of time: Solar cooking dispenses with a major share of the tedious, time-consuming work of gathering firewood, thus taking some of the load off the shoulders of the responsible women, men or children. In a box-type solar cooker, the food will not burn, needs no stirring, and therefore does not have to be watched. That, too, saves considerable amounts of time and energy. In Chinese reflector cookers, some dishes need shorter cooking time than on a conventional fire. In rural communities, time saved can be worth more than money saved. Ultimately, the social appreciation of saved time will depend on the woman's role and whether or not the time is saved at the cost of conversation. The macroeconomic importance of any time saved depends on its opportunity costs. Time savings should be evaluated on a socioeconomic - not economic - basis.
Less smoke: Solar cooking keeps smoke out of huts and is therefore seen as an especially clean way of cooking. Here, too, one must examine such arguments from a socioeconomic standpoint. While smoke from a cooking fire does have unhealthy effects, it also helps preserve food (which is intentionally stored in the same room). At the same time, it strengthens thatched roofs and makes them more water-repellent. Additionally, smoke keeps insects away and the fire serves as a source of light and heat at night. A solar cooker offers no such advantages.
Health effects: Solar cookers have multiple health effects: - air quality: The absence of smoke at the place of cooking means better air quality for women who used to cook over a wood or charcoal fire. In densely populated areas, that advantage is enjoyed by the population in general; - burns: Reflector cookers pose the danger of burning/blinding. On the other hand, conventional hearths and stoves are much more dangerous for children; - circulatory stress: Reflector cookers force the cook to stand out in the hot sun. In Mali, especially the pregnant and nursing mothers complained of frequent headaches and dizziness. Here, too, the pros and cons have to be carefully balanced on a case-by-case basis, i.e. generalizing is uncalled-for.
Nutritional effects: Solar cooking boxes cook food gently, thus preserving many nutrients and flavor substances that would normally be lost by cooking over a fire. On the other hand, it has not yet been - but should be - clarified to which extent slow cooking - particularly in box-type solar cookers, where the food is held at relatively low temperatures for considerable long time - could lead to decomposition with possibly toxic consequences, specially in aluminum vessels. Applied nutritional-physiological research would be appropriate in that connection.
Effects on balance of payments: Solar cooking saves fossil fuels like petroleum and bottled gas. For countries with a lack of foreign exchange and no indigenous oil or natural gee' that translates into less dependence on imported energy and resultant disburdening of the balance of payments. However, since solar cookers are still so sparsely disseminated, with only few poor target groups actually using them, it would hardly be worthwhile to even attempt to calculate such indirect consequential effects.
Ecological impact: The same applies to the consequential effects of reducing firewood consumption, namely a more sparing use of natural resources, preservation of the eco-system, less deforestation, desertification and soil erosion, groundwater protection, preservation of climate, avoidance of drought. The relative contribution of solar cookers to any of these is too minor to warrant any serious attempt at quantification. Contributions by other projects, programs and policies are of much greater significance, especially projects dealing with reforestation, massive dissemination of efficient wood-burning stoves in limited areas, control of lumber harvesting, and promoting efficient energy consumption in transportation and industry.