| Boiling Point No. 26 - December 1991 |
Prepared by Waclaw Micuta, REDI (Renewable Energy Development Institute), Editorial Extracts
These brief remarks summarize the findings and experience of REDI, acquired during many years of field and laboratory work. REDI has developed, improved and tested the equipment mentioned in this note, in the real conditions prevailing in developing countries of four continents. Their equipment works well and gives entire satisfaction. The REDI team hopes that their findings could be promoted in the countries where governments and people are really willing to break the vicious circle of misery and degradation of their environment.
A review of the technical and financial assistance provided to developing countries during the past decades does not offer optimistic conclusions. In spite of the assistance provided, the economic, social and political situation, in a great number of countries, has been deteriorating steadily. There is less water, less food, less firewood ...
This article does not investigate the reasons for this deplorable situation. Suffice to say, errors have been committed both by donors and recipients and in particular, the failure in production and promotion of fuel efficient stoves has not been an exception, but a part of the general trend of international technical assistance. The intention of this article is to voice the idea that better results could be obtained in future by semi-industrial or industrial production of stoves, in local independent workshops or enterprises, properly assisted by governmental policies, and if needed, by know-how and experience coming from abroad.
In spite of all efforts, the dissemination of improved stoves has been slow and the rate of deforestation hardly modified. Yet, the struggle to curb consumption of wood and to halt deforestation remains a top priority and must continue. Evidently, there is a need to have another look at the work accomplished so far and if possible, to voice some ideas on new methods and procedures which could bring better results than the methods employed.
Traditional cooking on an open fire gives about 10% Fuel Efficiency Rate (FER). Well-managed cooking on a protected open fire, using small dry pieces of wood, may reach about 20% FER. The simplest models of REDI fuel efficient stoves without chimneys give about 35% FER, while more elaborate models of family and community stoves give 45% FER.
The cost of simple REDI stoves is approximately the same as that of traditional charcoal braziers and they last much longer than braziers.
Community and family stoves in urban areas
The rural people do not cut many trees to cook their food. They use mainly wood waste collected around the villages. The bulk of charcoal and wood is consumed in the cities, of which a good part in institutions catering for a large number of people such as boarding schools, hospitals restaurant.c. etc
Promotion of fuel efficient stoves in institutions is relatively easy since savings on fuel can amortize investment costs in a relatively short time and the use and maintenance of stoves are relatively easy. REDI associates were the first to notice this situation. We designed and installed the first models of community stoves in Kenya in 1983.
Stoves for rural areas
REDI's associates tried hard, for many years, to find suitable stove models for villagers, made of locally available materials such as earth, clay or ceramics. It was a failure. Women accepted new stoves gladly but did not maintain or repair them. At the first difficulty they returned to the traditional three stones fire. After endless trials REDI developed stove models answering the two basic stove requirements - namely good combustion and good recuperation of heat produced. The stove consists of a fire box and a wind shield and if the wood used is dry and cut in small pieces and if the fire is well managed there is little smoke.
Long pieces of wood were, and still are, used in numerous countries for cooking on three stones. Combustion regulation is done by pushing them into the fire.
The REDI team has often been asked to design stoves to be fired with long wood. However, this cannot be done because of excessive consumption of firewood. In fuel efficient stoves, wood is burned in a relatively small and enclosed fire box. The wood must be dry and cut in small pieces and the inflow of air necessary for combustion must be regulated.
It is necessary to explain the nature and the properties of wood and charcoal and to equip women with tools to cut wood in relatively small pieces and to dry it before usage.
Although it is important to introduce alternative fuels replacing firewood, an immediate economy of wood could be achieved by replacing charcoal with wood. Charcoal is the most wasteful fuel used in developing countries. To produce one ton of charcoal it is necessary to cut at least 10 tons of good wood. In addition, heat recuperation in traditional charcoal braziers reaches only 15% of FER. Replacing charcoal braziers in the cities with simple, yet efficient stoves fired directly with wood, would alone result in about 90% economy of wood.
REDI feels strongly that good stoves cannot be produced by inexperienced people. The stove- making staff should be selected and trained at all levels of professional skills, including workers, foremen, engineers and managers. It will need time but will certainly speed introduction of good quality stoves. In parallel to the training of stove makers, one should train craftsmen able to install, maintain and repair stoves. A stove is a main component of the kitchen. The installation of a new stove is a good occasion to improve and rationalise kitchen work. Installers should also perform the important task of instructing the users in how to use the stoves properly.
Dispersed production rarely gives good results. Procurement of materials is difficult and their prices high. Quality control is problematic and performance and durability of equipment often poor. In-service training is not possible, productivity of labour is low and the cost of production high. REDI associates tried on several occasions to train individual stove makers, but results have never been satisfactory. Managers of the stove building centres had a tendency to become bureaucratic units dependent on external funding. On the basis of our experience, we think that the small-scale production of various models of stoves would be best carried out in local, well organised, independent workshops, or enterprises.
The installation of efficient stoves requires chimney pipes of different lengths, standardised elbows and chimney cowls. To put the pipe through the roof, additional accessories are needed such as storm collars and roof flashing. If such accessories are not easily available and at an affordable price, the stoves cannot give entire satisfaction to the users.
Role of Governments
All this complex work cannot be achieved without the active support and encouragement of national Governments. They should not interfere with the work of workshops, or enterprises, but should create favourable conditions for their activities by appropriate legal, financial and administrative measures. In particular, Governments should help enterprises to lower their production costs and thus to lower prices of stoves by exemption of import tax, sales tax and other financial burdens for steel sheet.
REDI, 5 rue du Vidollet, Tlx CH-427 993, CH-1202 Geneva, SW1TZERLAND
Tel (4122) 7337422 Fax (4122) 21 7970,
Attn. W Micuta
REDI is officially recognised as a public utility, nonprofit making institution.