safety & health
This website is dedicated to provide an overview of the work carried out by the Woodburning Stove Group (WSG) during the years 1980-1995 . The group does not exist anymore. Three reasons have prompted this work to be undertaken in spite of it being somewhat dated.
The group came into existence when one of us (Prasad) in the Faculty of Physics, Eindhoven University of Technology, Eindhoven, The Netherlands, was approached by Eric Ferguson, who was at the time engaged in an Energy Study of the Sahelian countries, with an innocuous question: ''What is the efficiency of an open fire?'' His problem was that the literature he had studied quoted the efficiencies of the open fire ranging from 3 to 10%. Being trained as a physicist he found more than factor three variation in efficiency for such an ancient ''device'' as simply unacceptable. The answer could be presumably found if a student could be enthused to carry out the needed experimental work. The other name mentioned in this website (Visser) was a student at the time in the Faculty of Mechanical Engineering and was willing to stick his neck out to carry out the experiments as part of his curricular requirements. Soon after he started producing efficiencies of 18% or so. This taken with a bit of literature study, while not providing the answer required by Ferguson, convinced a few of us (WSG in its embryonic form) that there is more to the stove business than meets the eye. With these results the group formally came into being in 1980 with participation of Faculties of Applied Physics and Mechanical Engineering at The Eindhoven University of Technology and TNO (The Netherlands Organization for Applied Scientific Research) at Apeldoorn. In 1982 the Catholic University of Leuven, Belgium joined the group. In 1985 MATRIX, a consultancy organization in Utrecht joined the Group to coordinate its field activities. Bulk of the work reported in this website took place in the eight year period 1980-87.
We now return to the third reason cited earlier. It could be rephrased as a question: ''Is it still worth bothering about stoves?'' - a slightly modified version of Willem Floor's question to his colleagues at the World Bank in 1985 or so. Hughart (1979) suggested that more than half the population of the world - roughly 2 billion people - ate food cooked on fires fueled by wood and agricultural/animal waste. What is the situation likely to be in twenty years' time from now? We will not go into a large scale presentation of energy studies carried out in the past twenty-five years or so, but present a couple of indicative observations.
World Energy Council (1994) presented an extensive study on the role of renewable energy in the world covering the 30 year period 1990-2020. They constructed two scenarios which were called ''minimum'' (equivalent of ''business as usual'') and ''maximum'' (''ecologically driven''). These scenarios showed that modern methods of using biomass to produce electricity and liquid fuels will contribute more than solar and wind combined in the minimum scenario or equal in the maximum scenario. For developing countries they specifically provided estimates for the traditional use of biomass as well. We will use their results to provide estimates of the populations using biomass in a traditional manner in 2020. Assuming that half the population in 1990 used biomass as their principal energy source, that is about 2642 million people, 838 mtoe translates into the annual per capita energy consumption of 13.322 GJ. Holding this as invariant with respect to time, in 2020 with the current policies scenario, there will be 3831 million people using biomass in a traditional manner. For the ecologically driven scenario this will become 3100 million people. In other words interpreting traditional use of biomass to be predomoinantly restricted to households for cooking, the stove users will grow by anywhere between 50 to 100% in the period 1990-2020.
A more recent study on biofuels in India by Parikh and Laxmi (2000) starts with the following statement: ''Rural population obtains 90% of cooking energy from biofuels such as fuel wood, crop residues and animal dung''. In other words our estimates above don't sound all that wrong.
At the time WSG started its work the rage was to save forests and thus improving cookstove fuel economy was considered to be the principal goal. Very soon it became clear that women and children in rural areas with literally zero equipment were collecting fuel from whichever source on hand to minimize their effort and thus were not responsible for deforestation. However urban areas where wood and charcoal are sold the deforestation effects are definitely of major concern. But still improved cookstove idea has persisted, but now with a shift in emphasis on the damage to health caused by the emissions from biomass fueled cookstoves. However, the perception of women is quite different as the following quote from Parikh and Laxmi reveals.''In the survey area women place the highest priority on water quality across all income levels followed by sanitation. It seems that water and sanitation are short term and immediate problems. On the other hand health effect of air pollution is a long term issue. In poor households health and inconvenience of biofuels are considered to be less significant''.
The brief discussion above brings out three points. If one insists on identifying the task of cooking as an energy problem, it still exists and what is more its absolute magnitude is larger than what it was when WSG started its work. Secondly cookstoves cannot be ''sold'' on the basis of simplistic slogans like ''save the forests'' or ''save your health''. Finally it requires a long term commitment with a broad range of skills - managerial, social, and technical to mention a few.
We will wind up this introduction with a few comments on the nature of WSG work. WSG from the outset recognized the futility of developing a design that would be acceptable to the large diversity - in terms of resources and in terms social practices - of the clientele that are the prospective customers for improved stoves. Thus the work was driven by the need to construct a systematic methodology of developing designs acceptable to users and to provide supporting data - mostly technical - that will ease the burden of the design chore.Thus the group developed a host of system diagrams from time to time for different audiences. However one of our colleagues in WSG (Verhaart) used to say: ''you have to put real things in them blocks''. We have tried to cover as many blocks as possible with as much information as possible. But we should admit that we have not achieved the goal set by our colleague. What is more (or maybe worse), this website is not complete in the sense it has not been possible to include all the work done by WSG. The group, in particular, carried out considerable amount of work on kerosene stoves, which is placed in the BTG website and can be accessed through the information provided at the appropriate place in this website. Further some work on institutional/commercial stoves carried out essentially in field installations have not been included. Finally the work done on indoor air quality both in the laboratory as well as in the field has not been possible to include in the present formulation. We hope to upgrade the website in the coming months. The principal component of the WSG work was laboratory based but supported by critical inputs from field work.