A Case Study of the Performance, Adoption, and Dissemination of...
Transcript of A Case Study of the Performance, Adoption, and Dissemination of...
ACaseStudyofthePerformance,Adoption,andDisseminationofImprovedClayCookStovesinRuralSenegal
MikhaelKazzi
Submitted in partial fulfillment of the requirements for the degree of
MASTER OF FOREST RESOURCES University of Washington
©Copyright2016
Program Authorized to Offer Degree:
School of Environmental and Forest Sciences College of the Environment
March9,2016
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Abstract
In Senegal, it is estimated that 82% ‐ 92% of the rural population depend on firewood as
their primary source of cooking fuel to prepare daily meals on a traditional three‐stone stove.
However, it is becoming increasingly difficult for women to harvest firewood due to
deforestation and rapid population growth. Previous studies have found that traditional stoves
not only require more wood for cooking, but also emit harmful amounts of smoke and
particulate matter negatively impacting the health of women and children present in the
cooking space. Improved cook stoves are a potential solution since they are designed to be
more fuel efficient and reduce smoke emissions. However, many studies have found that
introducing an improved cook stove into a community doesn’t ensure the stove’s adoption,
dissemination, and consistent use. In order for an improved cook stove to be successful, it must
be adapted to the traditional cooking methods and offer other advantages in addition to
improved fuel efficiency.
In this case study, I evaluate the performance, adoption, and dissemination of an
improved clay cook stove in a rural village in Senegal. I tested the performance of each stove
type by conducting the Water Boil Test (WBT) and the Controlled Cook Test (CCT). Results from
both tests find that the improved clay cook stove is significantly more efficient than the
traditional three‐stone stove. In addition to the quantitative performance tests, I conducted
interviews with the cooks to understand why and how the improved clay cook stove was
effectively disseminated and adopted within the community. Based on qualitative analysis of
the responses and the quantitative evidence of the clay stove’s superior performance, I
conclude that the improved clay stove is a sustainable solution for rural villages in Senegal to
meet their energy needs.
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TableofContents
1. Introduction…………………………………………………………………………………………………………….12. Background.…………………………………………………………………………………………………………….2
2.1. TraditionalStovesinSenegal……………………………………………………………………….……...32.1.1. LackofFuelEfficiency……………………………………………………………………………….42.1.2. SafetyHazards…………………………………………………………………………………………..42.1.3. NegativeHealthImpacts…………………………………………………………………………….5
2.2. CurrentImprovedStoveProgramsinSenegal……………………………………………...……...62.2.1. JambaarStove……………………………………………………………………………………….…..62.2.2. InStove……………………………………………………………………………………………………...82.2.3. CREATE!...........................................................................................................................................9
2.3. AdoptionofImprovedStoves……………………………………………………………………….…...112.3.1. AdaptingtoTraditionalWaysofCooking………………………………………………….112.3.2. Cost,Maintenance,andConstruction………………………………………………………..112.3.3. NeedsBeyondFuelEfficiency…………………………………………………………………..12
2.4. Participation…………………………………………………………………………………………………….143. BackgroundofResearchSite………………………………………………………………………………...15
3.1. TheVillageofNdorongSereer……………………………………………………………………….…..153.2. TheDjilorForest…………………………………………………………………………………………….....15
3.2.1. DominantFuelWoodSpecies:Acaciaseyal……………………………………………….163.3. TraditionalCookingProcess………………………………………………………………………………17
3.3.1. HarvestingFuelWood……………………………………………………………………………..173.3.2. TheThree‐StoneStove…………………………………………………………………………….18
3.4. TheCREATE!StoveinNdorongSereer………………………………………………………………193.4.1. BuildingtheCREATE!Stove……………………………………………………………………..20
4. Methods…………………………………………………………………………………………………………………254.1. TheWaterBoilTest(WBT)………………………………………………………………...…………….264.2. TheControlledCookTest(CCT)………………………………………………………………………..274.3. StatisticalAnalysis……………………………………………………………………………………………29
4.3.1. WaterBoilTest(WBT)…………………………………………………………………………….294.3.2. ControlledCookTest(CCT)……………………………………………………………………...29
4.4. InterviewMethods…………………………………………………………………………………………...305. ResultsandDiscussion………………………………………………………………………………………….31
5.1. TheWaterBoilTest(WBT)……………………………………………………………………………….315.2. TheControlledCookTest(CCT)…………………………………………………………………………355.3. InterviewResultsandAnalysis………………………………………………………………………….37
6. Conclusion……………………………………………………………………………………………………………..506.1. FutureResearch……………………………………………………………………………………………….52
7. WorksCited…………………………………………………………………………………………………………...54
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ListofFigures
Figure 1. Traditional three‐stone stove setup without the cooking pot………………………………………3
Figure 2. Traditional three‐stone stove setup with cooking pot………………………………………………….4
Figure 3. Flames from the traditional three‐stone stove being affected by the wind………………….5
Figure 4. A woman’s sandals melted by wind‐blown pieces of charcoal…………………………………….5
Figure 5. Smoke blows in the direction of a mother and her child while cooking lunch………………6
Figure 6. The charcoal Jambaar stove cooking lunch………………………………………………………………….7
Figure 7. The firewood Jambaar stove cooking lunch…………………………………………………………………7
Figure 8. The 60L and 100L InStove…………………………………………………………………………………………..9
Figure 9. The CREATE! stove preparing a meal………………………………………………………………………..10
Figure 10. A heavily decorated CREATE! stove………………………………………………………………………..10
Figure 11. A woman by two CREATE! stoves that contain the ash within their clay walls………..13
Figure 12. Women rejoice after completing a CREATE! stove………………………………………………….14
Figure 13. A map of the Djilor forest……………………………………………………………………………………….16
Figure 14. Acacia seyal growing in the Djilor forest…………………………………………………………………17
Figure 15. An example of the trunk pieces of firewood, xa sep……………………………………………….18
Figure 16. An example of the branch pieces of firewood, xa poignette……………………………………18
Figure 17. An example of the decomposed trunk pieces of firewood, xa pang…………………………18
Figure 18. A large stack of collected firewood in a family compound……………………………………….18
Figure 19. The raw materials required for building the CREATE! stove; sand, millet chaff, clay..21
Figure 20. Determining the base rock height for a small cooking pot (2‐3kg)…………………………..21 Figure 21. Determining the base rock height for a medium size cooking pot (4‐6kg)……………….21 Figure 22. Determining the base rock height more a large size cooking pot (8‐10kg)……………….21 Figure 23. Three rocks are cut to the determined height with a machete………………………………..22
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Figure 24. Three cut rocks are evenly spaced six‐fingers apart in a triangle to form the base…..22 Figure 25. An equal amount of raw materials are poured out onto a tarp……………………………….22 Figure 26. The women thoroughly dry mix the materials…………………………………………………………22
Figure 27. The women add water and mix until the pile is evenly moist…………………………………..22 Figure 28. Women making the clay mixture into balls used for building the CREATE! stove……23 Figure 29. Women making the clay mixture balls and placing them in a pile……………………………23 Figure 30. Two women building the CREATE! stove…………………………………………………………………23 Figure 31. Constructing the outside base of the CREATE! stove……………………………………………….24
Figure 32. A wet machete is used to cut chutes to help improve ventilation……………………………24 Figure 33. A wet machete slices the sides of the CREATE! stoves into an octagonal shape………24 Figure 34. Women decorating a recently completed CREATE! stove with seashells………………….25
Figure 35. The Senegalese national dish Ceeb u jen prepared for the Controlled Cook Test……..29
Figure 36. Graph displaying difference in mean boil time between the two stoves………………….32
Figure 37. Scatter plot of wood use and boil time between the two stoves……………………………..33
Figure 38. Graph comparing the mean boil time and wood weight used per participant………….34
Figure 39. Graph comparing of the mean weight of wood used for the Controlled Cook Test….36
Figure 40. Graph displaying the mean specific consumption for the CREATE! stove and 3‐stone
stove for the Controlled Cook Test…………………………………………………………………………………………..37
Figure 41. The CREATE! stove producing smoke at the beginning of a Water Boil Test…………….44
Figure 42. The traditional three‐stone stove producing smoke while cooking………………………….44
Figure 43. The degraded and broken rocks from a traditional three‐stone stove……………………47
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ListofTables
Table 1: List of Ingredients, Weight, and Recipe for Ceeb u jen………………………………………………..28
Table 2: WBT Results for the CREATE! stove and the 3‐stone stove………………………………………….31
Table 3: CCT Mean Weight of Wood Used and Specific Consumption per Stove………………………35
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ListofAbbreviations
ALRI Acute Lower Respiratory Infection
CCT Controlled Cooking Test
CREATE! Center for Renewable Energy and Appropriate Technology for the Environment
GACC Global Alliance for Clean Cook Stoves
GIZ Deutsche Gesellschaft fur Internationale Zusammenarbeit
ISO International Organization of Standards
PERACOD Programme for the Promotion of Renewable Energy, Rural Electrification, and
Sustainable Supply of Household Fuels
NGO Non‐Governmental Organization
WBT Water Boiling Test
WHO World Health Organization
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Introduction
Around the world, an estimated 3 billion people depend on biomass fuels to cook their
meals over a traditional open‐flame stove (WHO 2014, GACC 2014). These traditional stoves,
while free and easy to construct, are highly inefficient and require between 20% ‐ 50% more
fuel wood than alternative improved stoves (Bensch and Peters 2015, Kuhe et al. 2014, Ballard‐
Tremeer and Jawurek 1996). This can have detrimental impacts on nearby forests that already
face the pressures of deforestation from encroaching farmland, charcoal production, and cattle
herders (Hunter 2012). As fuel wood becomes scarcer, it becomes increasingly more difficult
and time consuming for women to collect as they must venture further into the bush searching
for new sources and travel longer distances to transport the wood back to their homes
(Honkalaskar et al. 2013). Additionally, traditional stoves release unsafe amounts of harmful
emissions that are proven to have significant adverse effects on the health of women and
children present in the cooking space (WHO 2014, Bruce et al. 2002, Ezzati et al. 2000). It is also
reported that these emissions account for at least 2% of global greenhouse gas emissions
contributing to global warming (Parker et al. 2014). All of these issues are more acutely felt in
regions like sub‐Saharan Africa, where more than 80% of the population rely on solid biomass
to meet their energy needs (Parker et al. 2014).
In this case study, I tested the efficiency and gathered user perspective on the
advantages and disadvantages of an improved clay stove introduced into a rural village in
Senegal. The research was conducted in the village of Ndorong Sereer, which had hosted me as
a Peace Corps Volunteer from 2013 – 2015. I brought four women from the village to an
improved clay cook stove training conducted by the non‐governmental organization (NGO)
CREATE!. At the training, the women were taught the benefits of using the improved stove over
the traditional stove and learned how to construct an improved clay cook stove using free and
local materials. The training was a success. The women returned to Ndorong Sereer and
immediately began constructing the new improved clay stoves in their own compounds and
training other women to build the stoves on their own. Within four months after the training,
every compound in Ndorong Sereer had at least one clay cook stove. In total, over 80 women
were trained to build a CREATE! stove and 108 clay cook stoves were built in Ndorong Sereer.
This case study compares the performance of the improved clay stove to the traditional
stove by conducting twenty‐five trials of the Water Boiling Test and eleven trials of the
Controlled Cooking Test. Additionally, interviews were conducted with fifteen women to gain
user perspective about the cook stoves and better understand why these stoves were so readily
adopted and disseminated throughout Ndorong Sereer. Ultimately, these stoves appear to be a
sustainable alternative to the traditional stove and could potentially be adopted in other
regions of Senegal and throughout West Africa.
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Background Senegal’s Rural Dependence on Fuel Wood
The country of Senegal is roughly the size of Nebraska with more than seven times the
population at approximately 14 million inhabitants, of which 57% are estimated to live in rural
areas (CIA 2016, Energypedia 2016). Like most of sub‐Saharan Africa, the rural populations of
Senegal are highly dependent on solid wood biomass to meet daily energy needs for cooking
(WHO 2014, UNEP 2015, Lawali 2006, Diop 2009, Bensch and Peters 2015). In Senegal, it is
estimated that firewood accounts for 82% ‐ 92% of the demand for domestic fuel use in rural
areas (Hunter 2012). In Senegal’s larger urban areas, the vast majority of the population uses
charcoal and liquefied petroleum gas (LPG) for cooking, whereas only 4% of the population in
Dakar uses firewood to meet their energy needs (Hunter 2012). Alternatively, 95% of the rural
population (Lawali 2006) depends on firewood as their primary source of fuel, consuming
around 1.03 million metric tons of firewood each year, approximately 74kg of firewood per
capita (Hunter 2012, Diop 2009). In the region of Fatick, where this study was conducted,
firewood accounts for over 90% of the region’s total energy consumption (Hunter, 2012).
Fatick’s estimated rural population of 629,000 uses 243 thousand metric tons of firewood each
year, approximately 390kg of firewood per capita yearly (Hunter 2012). For the majority of
Fatick’s rural population, fuel wood is harvested from classified forests and not purchased or
sold.
Senegal has set aside 6,231,00 ha of classified forests to be utilized for fuel wood
collection, soil conservation, and conserving biodiversity (Hunter 2012, ECODIT 2008). Fuel
wood is free and legal to harvest from designated classified forests as long as it is for personal
consumption and not harvested from living trees. Dead trees are scarce and not a readily
renewable resource in the northern half of the country due to the arid climate. When one
source of legal dead wood is depleted, women must venture out further in search of a new
source or else begin to cut the closer living trees and risk fines or imprisonment. Fuel wood
harvesting is not recognized as a primary cause of deforestation in Senegal, as women prefer
harvesting small segments of dead and dry wood (ECODIT 2008, Honkalaskar 2013). However,
the dominant factors contributing to deforestation ‐ subsistence agriculture, charcoal
production, uncontrolled fires, herders felling trees for fodder, and peri‐urban sprawl –
contribute to deforesting 40,000 ha of forested area each year, further diminishing the already
scarce supply of legal fuel wood thereby increasing pressure on women to illegally harvest
wood (FAO 2010, ECODIT 2008).
In the village of Ndorong Sereer, every family compound relied on firewood harvested
from the nearby Djilor forest as their primary source of fuel. The Djilor forest is approximately
1150 ha (Google Earth 2016) and one of 20 classified sylvo‐pastoral reserves in Senegal (Hunter
2012). It is used as the primary source of fuel wood by at least four rural villages and the small
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road town of Djilor. The Djilor forest is protected by the local Eaux et Forets (Water and Forest)
agents who work for the government and patrol the forest issuing fines for illegal harvesting
and poaching. Villagers are allowed to harvest firewood only from dead trees and a permit is
required to cut any living trees. However, fuel wood has become scarcer and the women are
constantly voicing their concerns about having to venture further and deeper into the forest to
find firewood. This not only takes time away from other household chores, but can be
dangerous for women, especially those pregnant or nursing, as they put more strain on their
bodies by carrying large bundles of firewood on their heads for longer distances. From
interviews conducted in Ndorong Sereer, women reported having to harvest wood every two to
three days to provide enough fuel to cook three meals a day on a traditional stove. One of the
objectives of this study is to discover if an improved clay cook stove will cook meals more
efficiently by using less wood thereby alleviating pressure on the forest and reducing the
amount of time spent harvesting firewood.
Traditional Stoves in Senegal
The three‐stone stove derives its name from the three stones, bricks, or cement blocks
spaced evenly apart forming a kind of triangle, leaving three openings between the stones to
insert firewood (Fig. 1). The ends of the firewood meet together in the center where a fire is lit
and a pot is placed on the top of the three stones over the open flame. The three‐stone stove is
commonly found all over the world as a method of cooking and heating because the materials
are free and easy to find. Furthermore, it is user‐friendly in that the stones can be arranged to
accommodate large pots, it can be adapted to the sizes and types of fuel based on the seasons,
the smoke acts as an insect deterrent, it can be used as a space heater, and the stove can be
easily moved and relocated (Barnes et al. 1993, Eregeneman 2003). The three‐stone stove is
very popular in rural sub‐Saharan Africa and in Senegal (Bensch and Peters 2015). Virtually
every family in Ndorong Sereer used a three stone stove before improved cook stoves were
introduced.
Figure 1. A set‐up of the traditional three‐stove stove. The stones are usually rocks or clay bricks of roughly equal size. Typically two large pieces of trunk wood are placed between each opening and the fire is started in the center and the cooking pot is placed on top to the stones.
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Lack of Fuel Efficiency
However despite its universal utility, it is widely accepted that the three‐stone stoves
are significantly less efficient than improved cook stoves, requiring more time and fuel wood to
perform the same cooking tasks (Ballard‐Tremeer 1996, Jetter 2009). This is because its open
layout is not conducive to focusing the heat energy to the cooking pot but rather allows the
heat to disperse (Fig. 2), which results in an inefficient use of wood (Vaccari et al. 2012). Several
field studies testing the fuel efficiency of the three‐stone stoves find that the stove uses 30%
more wood than other improved stoves (Vaccari et al. 2012, Bensch and Peters 2015).
Safety Hazards
The three‐stone stove fire is often affected by the wind and the flames are directed
away from the pot. The three‐stone stove’s lack of protection from the wind not only decreases
its energy efficiency, but is a serious safety hazard (Fig. 3). During the dry season, hot ash and
charcoal are swept up by the wind and can easily ignite the dry millet‐stalk walls of the kitchen.
This happened twice in a single day during my time living in Senegal, and many of the women
interviewed had revealed that their compound had also been burned down from a kitchen fire.
Interviews from local women also revealed that they and their children often burn their feet or
melt their sandals because they frequently step on wind‐blown charcoal (Fig. 4). Structurally,
the three‐stone stove is often uneven, unstable, and susceptible to breaking from the intense
heat. It is not uncommon for the pot to tip over and spill when cooking. However, the most
widely recognized health threat of the three‐stone stove is the indoor air pollution caused by
the incomplete combustion of fuel wood (Bruce 2002, WHO 2014, Maes 2012, Smith 2007).
Figure 2. The open‐layout design of the
three‐stone stove allows heat to easily
escape.
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Figures 3 & 4. The exposed flame of the traditional three‐stone stove is easily affected by the wind. Not only
does the wind redirect the heat from the cooking pot, but it can blow hot charcoal and ash outside the stove, burning
the sandals and feet of those walking around the stove and potentially starting kitchen fires. A woman’s sandal is
melted from stepping on hot coals that have been blown from stove.
Negative Health Impacts
Cooking with the traditional three‐stone stove poses many serious health risks for the women who cook with them as well as the children who are present in the kitchen (WHO 2014, Smith 2003, Barnes 1993, Ezzati 2000). The WHO (2012) estimates that 4.3 million people a year die prematurely from illnesses caused by air pollutants emitted from burning solid biomass fuels. Illnesses caused by inhaling smoke emissions include acute lower respiratory infections (ALRI), chronic obstructive pulmonary disease (COPD), tuberculosis, stroke, ischaemic heart disease, and lung cancer (WHO 2012). It is estimated that more than 50% of premature deaths among children under 5 are due to pneumonia caused by inhaling smoke and soot when present in the kitchen during cooking times (WHO 2014). In Senegal, current estimates are that 6,300 people suffer premature deaths annually due to exposure to indoor air pollution (UNEP 2015). Another WHO study (2007) found that 5,010 children under the age of 5 die prematurely from ALRI related effects annually and that indoor air pollution caused by burning solid biomass fuels accounts for 4.8% of Senegal’s national burden of disease (WHO 2007). These illnesses disproportionately affect women because cooking with the traditional three‐stone stove is done by women who constantly supervise the stove for most of the cooking process (Ezzati et al. 2002, Bensch and Peters 2015).
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Figure 5. Persistent smoke blows in the direction of a mother and her child as
she supervises the cooking pot while preparing lunch.
Due to the nature of the three‐stone stove, the women must be present for the
entire cooking process to ensure the pot does not tip over, fan the flames, constantly adjust the wood, and prevent the hot ashes from being swept up by the wind (Fig. 5). Their prolonged daily exposure to smoke increases their risk of contracting one of the many illnesses attributed to fuel wood smoke emissions. With the population and the rate of fuel wood use expected to rise in Senegal, it can be assumed that there will be an increased number of illnesses and deaths related to exposure to emissions from cooking with traditional three‐stone stoves (Arnold 2006, Bensch and Peters 2015). Improved cook stoves are a potential solution to reduce the amount of fuel wood use, reduce the amount of smoke emissions, and reduce women’s and their children’s’ exposure to smoke emissions (Bensch and Peters 2015). Current Improved Cook Stove Programs in Senegal Jambaar Stove
Since the 1970’s, there has been a concerted effort by the Senegalese government and NGO’s to alleviate the pressure on the country’s forests from fuel wood extraction and charcoal production by providing rural and urban populations with improved cook stoves (Bensch and Peters 2013). The improved cook stove program was slow to catch on during the 1980’s and 1990’s due to a lack of potential markets and field testing to adapt to local ways of cooking (Barnes 1993, Bensch and Peters 2013). However, in the past decade, the Senegalese government energy program, Programme for the Promotion of Renewable
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Energy, Rural Electrification, and Sustainable Supply of Household Fuels (PERACOD), has worked in cooperation with the German organization Deutsche Gesellschaft fur Internationale Zusammenarbeit (GIZ) to develop an industry and market for an improved cook stove called the Jambaar stove (Bensch and Peters 2013).
The Jambaar stove is a portable metal stove with a ceramic top insert intended to conserve heat and effectively direct it to the cooking pot (Bensch and Peters 2013). There are two types of Jambaar stoves; one intended for urban populations who prefer cooking with charcoal (Fig. 6) and another for rural populations who primarily cook with fuel wood (Fig. 7). In urban Senegal, charcoal is virtually the only solid cooking fuel used by families because it is less expensive than fuel wood, it burns cleaner thus producing less smoke, it stores better in urban compounds, and the cooking temperature is easier to control (Bensch and Peters 2013). From lab testing in Dakar sponsored by the national government, the Jambaar stoves are reputed to use 40% less charcoal than the traditional charcoal stove, however, field testing reveals charcoal savings of around 25% (PERACOD, Bensch and Peters 2013). While the Jambaar is designed to significantly reduce the need for charcoal, it is not designed with a chimney or ventilation mechanism to reduce smoke exposure. The decrease in smoke related illnesses may not be as pronounced while using the Jambaar stove. However, it is known that charcoal emits less and ‘cleaner’ smoke than fuel wood, and reducing charcoal use is the first step to reducing smoke (Smith and Metha 2003, Bensch and Peters 2013).
Figure 6. The charcoal Jambaar stove
cooking lunch. The cooking pot is
placed on top of the charcoal which is
contained in clay insert at the top.
The flames are directed to the bottom
of the cooking pot.
Figure 7. The firewood Jambaar stove
preparing a meal. The cooking pot is
placed on top of metal holds and fuel
is fed through the single opening at
the bottom of the stove. (Photo
Credit: David Snyder, The Banner:
Stove Project Saves Trees in Senegal,
2016)
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The Jambaar stove is manufactured by local artisans and is currently available in
most mid to large size cities in Senegal. Manufacturing and distribution of the Jambaar stove began in Dakar in 2006 and spread to Kaolack in 2007. By the end of 2009, an estimated 71,600 Jambaar stoves had been distributed in Dakar and an additional 6,900 stoves in Kaolack (Bensch and Peters 2013). Currently between 3,000 and 6,000 stoves are produced and sold every month in these cities (PERACOD 2016). Depending on the size and type of the stove, prices vary from 4,500 cfa to 9,000 cfa (~$9US ‐ $18US). The production and price of the Jambaar stove is not directly subsidized, although GIZ trains local manufacturers to make quality stoves to meet established standards and helps develop marketing strategies for women’s groups and private retailers (PERACOD 2016, Bensch and Peters 2013). NGOs also participate in marketing and selling the Jambaar stove, such as the Beer‐Sheba Project which also runs a sustainable charcoal production center in an area about an hour outside of Dakar. To discourage counterfeit stoves, authentic Jambaar stoves have a special label and the local manufacturer’s name is imprinted on the inside of the clay insert.
The charcoal Jambaar stove is the most widely distributed improved cook stove in Senegal and its use in urban areas has contributed to reducing the country’s total charcoal consumption by around 1% (Bensch and Peters 2013). This 1% reduction is enough to have a significant impact on the amount of deforestation driven by charcoal production (Bensch and Peters 2013). The fuel wood Jambaar stove has shown to have similar energy reductions in rural areas, using up to 30% less wood than the traditional three‐stone stove. However, cooking with the Jambaar is not as widespread in villages most likely because of the stove’s high initial cost, its unavailability in smaller road towns, and because fuel wood, while scarce, is still free whereas one must pay to cook with charcoal. InStove
Another improved stove recently introduced to Senegal, though on a much smaller scale, is the InStove (Fig. 8). The InStove is a large metal stove which comes in 60L and 100L sizes and is reported to reduce fuel wood use by up to 80% (InStove 2016). The InStove has the highest rating for both fuel efficiency and reduced smoke emissions by the Global Alliance for Clean Cook Stoves (GACC). In 2013, InStove collaborated with GIZ to distribute 100 InStoves to cooks preparing meals for the hundreds of people attending one of Senegal’s largest religious festivals. There is no further evidence of future distribution and the stoves can only be imported and assembled on site, however the company states that it is currently looking into manufacturing the stoves domestically in Senegal. The stoves are very expensive even with the “humanitarian discount”, retailing at $885 ‐ $995 depending on the size. In addition to the prohibitive initial cost and limited availability, the stoves are very heavy (38 – 50kg), bulky, difficult to maintain, and do not conform to the traditional way of cooking. These factors make it unrealistic for the InStoves to become widely used and disseminated throughout Senegal.
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The CREATE! Stove
In the present study, I examined an improved clay stove designed by the NGO CREATE! using free and local materials intended to reduce fuel wood consumption and cooking time while improve women’s health by reducing both smoke emissions and exposure to smoke. The stove design was created by Barry Wheeler, Ph.D., Founder, and Executive Director of the Center for Renewable Energy and Appropriate Technology for the Environment (CREATE!). Founded in 2008, the mission of CREATE! is:
“to assist indigenous rural populations in developing countries in improving the conditions of their lives through the application of renewable energy and small scale technologies that are appropriate to the local environment and which employ methods and strategies of community self‐development that are likewise appropriate, based on local organization, participation, and social mobilization to maximize self‐reliance and self‐sufficiency.” (Grigsby 2013)
In addition to improved clay cook stoves, the NGO CREATE! provides aid to rural communities by helping build wells fitted with solar pumps, by helping establish community gardens, and by conducting workshops to improve financial literacy. CREATE! promotes clay cook stoves as a way to reduce firewood consumption, reportedly by up to “50%‐70%”, from the traditional three‐stone stove (CREATE! 2016). With the traditional three‐stone stove, women balance a pot on three evenly spaced stones or bricks over an open fire. The improved clay stoves are inspired by the three stone cooking method while still using the three stones as a base, but fully enclosing the cooking pot (Fig. 9, Fig. 10). Therefore, the clay walls are able to conserve and concentrate the heat onto the cooking pot and protect the fire from the wind.
The clay stove is an appropriate technology for rural Senegal because it uses free, locally available materials and does not change the fundamental method of cooking; women are still placing a pot on top of three stones although they insert firewood through a single bottom opening instead of three openings. The clay stoves are made of equal parts sand, clay, and
Figure 8. The 60L and 100L InStove.
The InStove is very durable, efficient,
and emits very little smoke. However
it is too expensive, bulky, and poorly
adapted to traditional cook practices.
(Photo Credit: InStove website 2016)
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millet chaff, all which are free and easily accessible in many villages in Senegal. If the stove cracks or breaks, there is no need for a specialized technician or access to outside materials as the women in the village are equipped with both the knowledge and materials to repair or replace a stove. Given the successful dissemination, earnest adoption, and use of the CREATE! clay cook stove from several villages, it is apparent that it is an appropriate technology for rural villages in Senegal.
Figure 9. A CREATE! stove preparing a meal. The clay walls of the CREATE! stove help contain and direct heat to the cooking pot, protect the fire from the wind, and help stabilize the cooking pot.
Figure 10. A CREATE! stove heavily decorated with seashells. Many of the women enjoyed embellishing their stoves with their personal touch when they were being built.
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Adoption of Improved Cook Stoves
The advantages and benefits of an improved cook stove can only be achieved insofar as the stove is accepted and adopted within the community. The community must use the stoves correctly, consistently, and fully replace the less efficient traditional stoves (Burwen 2011). However, it is not as straightforward or intuitive for a community to fully accept a stove simply because it can save them time cooking and gathering fuel wood. Multiple cook stove programs have failed because the stoves were not designed to be compatible with traditional cooking methods, they were too costly to purchase and maintain, and the stoves did not offer any additional benefits besides reduced fuel wood consumption (Barnes et al. 1994, Soini and Coe 2014).
Adapting to Traditional Ways of Cooking
To maximize its chances of being adopted, the improved cook stove should be as simple,
straightforward, and convenient to use as the traditional cook stove and support local cooking
and fuel use practices (Soini and Coe 2014). A new stove is less likely to be adopted if it requires
changes in the cook’s posture by causing them to bend or squat more frequently (Quadir et al.
1995). Furthermore, the stove should be adapted to the appropriate pot shape and sizes and
should not make it difficult to place or remove the pot (Barnes et al. 1994). While the improved
cook stove might require less time to cook and use fuel more efficiently, it should also be
designed to fulfill a broad range of relevant cooking tasks. For example, the cook should be able
to easily adjust the heat output to cook dishes that require a sustained low‐level of heat as well
as dishes that require cooking with intense heat (Soini and Coe 2014). The improved cook stove
should be adapted to the traditional type and sizes of fuels used in the area (Quadir et al.
1995). A common design aspect of improved stoves is to use smaller pieces of solid fuels,
however, depending on the community, cooks might be reluctant to put in the extra time and
labor required to break up larger solid fuels for the new stove. This problem occurred in Kenya,
where an improved cook stove required smaller pieces of wood and the women did not have
the tools or the time to split the fire wood before cooking and as a result the stove was
abandoned (Barnes et al. 1994).
Cost, Maintenance, and Construction
The upfront cost of an improved cook stove can be a significant barrier to its adoption
(Barnes et al. 1994). In general, it has been found that improved cook stoves are more likely to
be adopted in rural areas where there is a scarcity of fuel wood, especially in arid regions like
northern and central Senegal where trees grow back slowly, and harvesting fuel wood is an
arduous task (Barnes et al. 1994). However, rural populations are often very poor and do not
perceive purchasing an improved cook stove as a worthwhile investment. Fuel wood, while
scare, is often free to harvest so there is no incentive to save on fuel costs by purchasing a new
12
stove, which makes adopting the free CREATE! clay stove a more appropriate alternative (Soini
and Coe 2014). For rural populations, constructing an improved stove using local materials
could be an effective alternative. While this approach requires outside training and collective
labor, it has proven effective in several cases, including the present study, where collective
participation became a social benefit rather than cost (Soini and Coe, 2014). All of the materials
are free and easily accessible. Stove maintenance is simple considering there is no need for a
specialized technician or costly spare parts. The local women have the knowledge and skills to
rebuild the stove wherever and whenever needed. Furthermore, with the new knowledge, skills
and an entrepreneurial spirit, women can share their skills with nearby villages, teaching them
how to build an improved cook stove for a nominal fee. This was evidenced in the present case
study when the women of Ndorong Sereer were invited to the nearby villages of Ndorong
Wolof and Yerwago to conduct a training on how to build the CREATE! stove and were paid to
help construct them in family compounds.
Another option to promote adoption is to make improved cook stoves more affordable
to rural populations through subsidies provided by the government or international community
in the form of carbon credits (Soini and Coe, 2014; Bensch and Peters 2015). In Senegal, where
the Jambaar stoves are not subsidized and purchased primarily by middle‐class city dwellers, a
study by Bensch and Peters (2015) found that improved cook stoves had a 96% adoption rate in
98 households in several different villages when they were given out for free. While providing
free stoves throughout rural Senegal is not a sustainable solution, it does reveal that the stove
is strongly adapted to these communities and perhaps a significantly lower price could be a
motivating factor in encouraging rural populations to purchase improved stoves. However,
before any financing mechanisms are put into place, Bensch and Peters (2015) recommend
conducting future studies in the region to research the driving forces behind adoption behavior;
examining factors like the households’ willingness‐to‐pay, pre‐existing knowledge and
awareness of the benefits of cook stoves, and perceived and actual levels of wood‐fuel scarcity.
The most successful cook stove programs, however, have not been heavily subsidized to ensure
sustainable market development without government support (Barnes et al. 1994). If a
subsidized program were to lose funding, a return to higher prices might dissuade users from
replacing their stoves. There are competing claims to the efficacy of subsidizing cook stoves and
the degree and conditions of subsidies should be tailored to local conditions (Soini and Coe
2014).
Needs Beyond Fuel Efficiency
While fuel efficiency and smoke reduction are very important positive attributes of an
improved cook stove, these reasons alone might not be sufficient to replace the traditional way
of cooking (Barnes et al. 1994). Traditional stoves are very adaptable to different fuels and pot
sizes, they’re easy to cook with, transportable, and can be built almost anywhere. Oftentimes
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improved stoves are fixed in one place and can work with only a few pot sizes, they might
require different fuels or more work to break up firewood, and they can change the cooking
procedure. In order to be adopted, they should offer the same or more benefits than the
traditional stove. In various countries, traditional stoves are also used to provide lighting, space
heating, pest control, smoke foods, and for drying thatched roofs (Quadir 1995, Barnes et al.
1995).
While these supplemental uses are not common in Senegal, the improved stove is able
to compensate for problematic aspects of the traditional stove in addition to fuel efficiency and
smoke reduction. Cooking with traditional stoves is a dirty process and the women often
complain about their kitchens, pots and pans, food, and clothing being covered in ash. The
design of improved cook stoves prevents the wind from sweeping through the fire and picking
up the ashes, leaving the ash to settle at the base of the stove. Additionally, by protecting the
fire, it prevents hot ashes from being blown by the wind and igniting the dry grass walls of the
kitchen. This safety aspect allows women to leave the kitchen while cooking to complete other
tasks without having to constantly supervise the fire. Another common complaint when using
the traditional stove is the instability of the cook pot when placed on the three stones. When
stirring the pot or when it is at a rigorous boil, it can tip over. Furthermore, the stones are
susceptible to breaking when constantly exposed to intense heat. These issues are also
remediated by the improved cook stove which securely holds the pot in place and is more
durable. The thick clay walls of the cook stove also provide insulation making it easier to keep
food warm for long periods of time. Furthermore, the clay stove can be personalized and
decorated and many consider it a more attractive structure than the three rock stove. Since the
women often help build each other’s clay stove, it is also sign of community solidarity. These
are all significant advantages supplemental to fuel efficiency and smoke reduction, making the
clay stove more readily adaptable and adoptable by the community.
Figure 11. A woman sits proudly by
her two decorated CREATE! stoves.
The clay walls protect the fire from
the wind, keep the ashes contained
within the stove, and allow women to
leave the cooking pot on the stove
unattended.
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Participation
Many of the shortcomings and disadvantages of an improved cook stove can be avoided
if the community is encouraged to provide input and participate in the design and technology
dissemination process. Often, improved cook stoves are designed and manufactured without
prior knowledge of community needs and preferences (Bailis 2007, Smith 1994). This leads to
stoves that are incompatible with traditional methods of cooking, lack realistic solutions in
regards to stove production and maintenance, and misjudge local priorities. The InStove is an
example of a cook stove program that did not consult local communities before it was designed
and disseminated. Even though the InStove ranked highly on fuel efficiency and smoke
reduction, its design is ill‐adapted to traditional ways of cooking, is bulky and dissonant with the
kitchen environment, is exorbitantly expensive to purchase and maintain, and is not well suited
for sustainable dissemination.
In contrast, the CREATE! clay stove design was inspired by traditional cooking methods
and relies heavily on community feedback and participation to construct and disseminate their
stoves. The training staff teaches motivated volunteers from other communities who then bring
back skills and knowledge to their village and provide outreach by recommending other nearby
villages to receive cook stove training. The CREATE! stove design is not a one‐size‐fits‐all model,
but instead allows women to make adjustments according to their personal cookware and fuel
type. The women are empowered to collectively participate for the benefit of their own
households and community as a whole by using local knowledge, resources, and labor to plan
and implement the stove dissemination. CREATE!’s bottom‐up approach fosters collective
participation which promotes self‐reliance and self‐confidence, rather than dependency on a
top‐down approach (Sesan 2009). A bottom‐up approach has greater potential to generate
more socially and technologically appropriate solutions which are more likely to be adopted
thereby ensuring long‐term sustainability (Sesan 2009).
Figure 12. Women rejoice after
completing a CREATE! stove for their
neighbor. The more someone helped
out, the more help they would receive
when it was their turn to build a
CREATE! stove.
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BackgroundofResearchSite
The Village of Ndorong Sereer
The present research was conducted in the village of Ndorong Sereer, which is located in the Foundiougne Department in the region of Fatick. The average temperature in the Fatick region is 27⁰C and has an average precipitation of 611mm per year (Climate‐Data 2016). The village is 7 km south of the road town of Djilor and accessible only by a bush path which connects Djilor to Sokone. Recounted from oral history, Ndorong Sereer is said to have been established in the late 18th century and has been inhabited predominantly by the Sereer ethno‐religious group (Ndiaye, 2014). Ndorong Sereer currently supports a population of around 900 people, the majority of whom are children under the age of 15. The population fluctuates with the seasons, with more people returning from school or work in the city to help farm during the summer months coinciding with the rainy season. The primary sources of income are peanut farming, cattle raising, fishing, and basic masonry work. All agriculture in the area is dependent on the rainy season as there is no man‐made system of irrigation. The main crops grown for food include millet, rice, corn, and beans. In the dry season, several households maintain small market gardens which are watered by hand from a nearby well. The Djilor Forest
The Djilor forest is approximately 1,150 ha (Google Earth 2016) and its border forms a right triangle between the villages of Djilor, Yerwago, and Ndorong Sereer. The forest extends the entire length of the 7 km bush path from Djilor to Ndorong Sereer and 3 km from Ndorong Sereer to Yerwago (Fig. 13). The Djilor forest is protected by the local government funded Eaux et Forets (Water and Forest) agents who patrol the forest issuing fines for illegal felling and poaching. Villagers are allowed to harvest firewood only from dead trees and a permit is required to cut any living trees. The forest is utilized between four villages: Ndorong Sereer, Yerwago, Lambey, and Djilor. Primary forest products include firewood, construction wood for fence posts or roofing, large branches for tool handles, leaves, seeds, and fruits used for cooking, and medicines made from bark and roots. There are no published studies detailing the characteristic vegetation and species composition in the Djilor forest. However, from my experiences living proximate to the forest for two years, I have identified the numerically dominant forest species in descending order: Shittim wood (Acacia seyal), Winter thorn (Faidherberia albida), Jujube (Zizyphus mauritiana), Desert date (Balanites aegyptiaca), Baobab (Adansonia digitata), Cola tree (Cola cordifolia), Egyptian thorn (Acacia nilotica),African locust bean (Parkia biglobosa), and Silk cotton tree (Ceiba pentandra).
Before the rainy season, farmers burn the dried underbrush in the Djilor forest to encourage regeneration for their livestock to graze after the first rain. During this time, the farmers also cut live thorny branches to make ‘dead fences’ along the perimeter of their fields or to protect newly planted trees. During the rainy season (July‐September), the low lying areas of the Djilor forest are flooded and there are several seasonal streams which connect to the larger river in the west of the forest. Salt water from the river often floods into the forest and
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once the water evaporates or soaks into the earth, salt is visible on the topsoil. Late in the dry season (April‐June), it is common for migrant herders to heavily degrade the forest for their grazing animals. The herders will often cut large branches, whole crowns, or even the entire tree as fodder for their livestock. This practice has very detrimental impacts on the forest and is a major cause of deforestation. The Eaux et Foret agents have tried to prevent and dissuade herders from this practice, but the agents have trouble enforcing the law. The agents must catch the herders in the act before they can fine or imprison them, but this is very difficult since the herders are constantly on the move and often travelling deep into the forest. If a herder is found by a pile of cut branches, they often say they are just passing through and it was another herder who cut the trees. Furthermore, the Eaux et Forets agents and the herders are oftentimes from the same ethnic group, and if they have a common last name, the agents will often let them go or simply ask for a bribe.
Dominant Fuel Wood Species: Acacia seyal
Acacia seyal is a dominant tree species in the Djilor forest and is the preferred choice for firewood in Ndorong Sereer (Fig. 14). It is native to Senegal and the Sahel region as well as parts of eastern and southern Africa (Orwa, 2009). Acacia seyal is one of the most prevalent species in the Sahel savannah and often “occurs as a pure forest over quite large areas of country” (Orwa, 2009). Considered to be a gregarious species, A. seyal often grows close together in pure stands forming impenetrable thickets. Acacia seyal is tolerant to flooding, fire, salty soils, and high pH soils (6‐8) (Orwa, 2009), all of which are common in the Fatick region. The tree can reach up to 17m tall with a 60cm diameter at breast height (Orwa, 2009). A few characteristic
Figure 13. The Djilor forest
extends from Djilor to Ndorong
Sereer and Yerwago. (Google Earth
2016)
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features of A. seyal are that its crown branches out into an umbrella shape and its bark is either a dark rust or light green color. Research conducted in Saudi Arabia indicates that the wood of A. seyal has a specific gravity of .627 g cm‐3 and a gross heat of combustion at 4,579 kcal/kg (El‐Juhani 1996). The dried wood is recognized as exceptional firewood in Senegal as well as other countries (Orwa, 2009). This study exclusively used firewood harvested from Acacia seyal for the boil and cook tests because of its prevalence and widespread use as firewood in Ndorong Sereer and also to limit the variable differences of cooking rates potentially caused by using other species of wood.
Figure 14. Acacia seyal growing along the bush path from Ndorong Sereer to Djilor. It is the dominant species in the Djilor forest and the preferred choice for firewood. The Acacia seyal is recognizable by its bright orange or yellowish green bark and umbrella shaped crown. (Photo Credit: Nicola e Pena, Google Earth 2016)
Traditional Cooking Process Harvesting Fuel Wood
In Senegal, harvesting firewood is a woman’s chore and the women of Ndorong Sereer heavily rely on the Djilor forest for fuel wood to cook meals. When harvesting firewood, the women search for dead trees or branches with no foliage or signs of new growth and then use crude axes to split the wood. Once they have gathered their desired amount of firewood, they pile it up in a bundle and tie the bundle with a piece of cloth or rope which they then balance on their heads as they make their way back to the village. Firewood bundles vary in size and weight depending on who is harvesting; some women prefer smaller bundles of around 10kg while others prefer heftier bundles weighing as much as 30kg. The larger bundles will last longer, but are more difficult to bring back, while the smaller bundles do not last as long, but
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those women prefer to harvest firewood more frequently. There are three different types of firewood (Fig. 15,16,17,18); xa sep which are large split trunk pieces often ranging from 40cm to 1m in length, xa poinette which are small to medium sized dead branches, and xa pang which are old, brittle, decomposing chunks of trunk or bole wood. When cooking with the three‐stone stove, most women in Ndorong cook with xa sep and xa poinette, using xa sep as the primary source of fuel and breaking up xa poinette (the dead branches) to help ignite the fire and to stoke the fire while cooking. While most women have a preference for cooking with a certain type of firewood, nearly all of the women combine the different types of firewood when cooking instead of cooking exclusively with just one type.
Figure 15, 16, 17, 18 (Clockwise from top left). Examples of the different types of firewood; xa sep which are the larger trunk pieces, xa poinette which are the smaller branch pieces, and xa pang which are the drier, older and smaller trunk pieces. Fig. 18 shows a large stack of collected firewood. Women collect more firewood before the rainy season to stock up since harvesting in the Djilor forest is off‐limits during that time.
The Three‐Stone Stove
Before the improved clay stove was introduced to the village, all of the women in Ndorong Sereer cooked with the traditional three‐stone stove. The three‐stone stove derives its name from the three stones or bricks spaced evenly apart forming a kind of triangle, leaving three openings between each stone to insert firewood. The ends of the firewood meet together in the center where a fire is lit and a pot is placed on the top of the three stones over the open flame. In Ndorong Sereer, women used hardened clay or cement bricks as their three‐stone base because they were flat topped and easily accessible. To start the fire in the three‐stone
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stove, the women place two pieces of firewood, typically xa sep trunk pieces, in each of the three openings and break up two or three xa poinette branches placing them in the center of the stove. Tinder composed of crushed millet stalk, dried weeds, or wood shards are then placed in between the xa poinette branches and the tinder is ignited with a match. This firewood structure with the large trunk pieces on the bottom with broken branches on top and tinder in between helps ensure a complete ignition and burn. The women recognize that excessive smoke often occurs at the beginning of the ignition due to a haphazardly constructed firewood pile or an insufficient amount of dead branches or tinder. Furthermore, the women are aware that drier wood produces less smoke than partially dried wood.
Once a good fire is established and the trunk pieces are burning well, the women place the pot on top of the three‐stone stove. A level surface and flat topped stones or bricks are preferred because the pot is liable to tip over when the water reaches a rigorous boil, when stirring the pot, or when placing the rice on top of the pot. After the meal is cooked the women remove and extinguish the firewood to use for the next meal. The women cook three meals a day; breakfast, lunch, and dinner. For breakfast, the fresh millet is prepared the night before and reheated the next morning along with the sauce from the previous dinner. In Sereer families, breakfast and dinner typically consist of a millet couscous base accompanied by sauce or milk while lunch is rice accompanied by fish, vegetables, or a sauce. Cooking meals with sauces requires two stoves while cooking a lunch of rice and fish simply requires a single stove since the rice is traditionally steamed then cooked in the same pot as the vegetables and fish. The CREATE! Stove in Ndorong Sereer
Throughout my Peace Corps service, I had often heard the women in the village complaining about the burden of collecting firewood. Firewood had become difficult to find and the women had to take more time out of their day to venture deeper into the forest searching for firewood and then carry it for longer distances back to village. I had observed that cooking with traditional cook stoves required large amounts of firewood and had realized that using an improved cook stove which required less wood could be a potential solution. However, imported and even locally fabricated improved cook stoves require an up‐front cost and typically require further costs and technical expertise to repair. Furthermore, in many cases the improved stove design does not take into account traditional cooking methods and are not adaptable to local conditions. These factors can make it difficult for users to embrace, disseminate, and adopt the new cook stove technology.
After researching cook stove programs in Senegal, I discovered CREATE! (Center for Renewable Energy and Appropriate Technology for the Environment), an NGO which trains motivated community members how to build improved clay stoves using free and local materials. I selected four motivated women from Ndorong Sereer to attend the CREATE! cook stove training at the NGO’s center in Fass Barigo. The field staff were all Senegalese who spoke the local languages. Thus, they were able to effectively convey to the women the advantages of using the clay stove over the traditional stove and how to properly build the clay stove. This is significant because oftentimes, NGOs do not conduct trainings in local language making it more difficult to explain detailed procedures and less effective at motivating people to adopt a new technology. The staff built a cook stove from the raw materials, explaining what they were
20
doing and why they were doing it for each step in the procedure. At times, they would ask the women to recall and repeat steps to ensure they had retained the information. After an involved demonstration on how to build the clay stove, the women were asked to build two stoves by themselves in order to demonstrate they retained the knowledge, to ask questions, and to make mistakes before they taught members from their own community.
After successfully building two stoves, the women returned to Ndorong Sereer and started building the stoves in each other’s compounds. They told the other women about the training and the advantages of the improved cook stove and these women responded very positively to the new stove and also wanted have CREATE! stoves in their compound. If a woman wanted a stove in her compound, she had to help build the stove of the women before and after her. When it was time to build the stove for her compound, she had to collect and prepare all of the materials beforehand as well as provide lunch, tea and candy for all of the women who came to help. In addition to the four women trainers, every compound had between six to ten women participate in building the clay stoves. The more often a woman participated in building the stove at different compounds, the more women would recognize her efforts and cooperate to help build her stove. In one day, the women could finish constructing two clay stoves in four different compounds, completing a total of eight stoves. Within four months after the training, every compound in Ndorong Sereer had at least one clay cook stove. In total, over 80 women were trained to build a CREATE! stove and 108 clay cook stoves were built in Ndorong Sereer. Building the CREATE! Clay Stove
The clay stove design uses the same principle as the three‐stone design; essentially using three stones to support a pot over an open flame. However, the clay stove is form fitted around the pot and the stones allowing for increased heat conservation, protection from the wind, and pot stability while cooking. Making the clay stove involves five sequential phases; Phase 1: Processing the materials and preparing the stone base, Phase 2: Dry mixing the materials, adding water, further mixing, and forming the wet mixture into clay balls, Phase 3: Layering the clay balls into the stove structure and the base, Phase 4: Applying finishing touches to the stove with a machete by forming the distinct octagonal shape, smoothing out the edges, and carving out the smoke holes, Phase 5: Drying and decorating the stove. Phase 1: The clay for the stoves is composed of equal part clay, sand, and millet chaff, all of which are locally available and free to most people in Senegal (Fig. 19). In regions where millet is not predominantly grown, millet chaff can be substituted by corn chaff or dried weeds. The clay is typically found in shallow quarries outside the village where people extract clay to mix with cement for creating bricks. When extracted, the clay comes out in large compact chunks and is pounded into a powder‐like consistency. Sand is plentiful nearly everywhere in Senegal. Once collected, it needs to be sifted to remove any detritus. In regions that grow millet, millet chaff is readily available. Women winnow the chaff from the millet seed often in the same place every day leaving a large pile of chaff material. The millet chaff also needs to be sifted to remove the woodier stems and stalks.
21
It takes two 25 liter buckets of each processed material to make one stove for a medium
sized pot. The clay stoves can be constructed to accommodate pots of any size, though most cooking pots range from holding 2kg to 10kg of water. Nearly all of the women in Ndorong Sereer constructed two clay stoves for each of their compounds, a smaller stove for cooking sauces in a smaller pot and a larger stove for cooking rice and millet in a larger pot. The smallest stove constructed was for a 2kg pot and the largest was for a 10kg pot. The base of the stove requires three flat rocks or bricks spaced evenly apart on a level surface. The stone or bricks should be relatively similar in width and length, around 15‐20cm. The height of the stone or brick depends on the size of the stove (Fig. 20, 21, 22). If a stove is intended for a smaller pot (2‐3kg), the stones’ height will be equivalent to the tip of a thumb extended upward after forming a fist. For a medium size pot (4‐6kg), the stones’ height will be that of two stacked fists. The height of the stones for a large size pot (8‐10kg) will be the height of the thumb extended on the top hand of two stacked fists. Once the appropriate height has been determined for the stove, the three stones are cut to the same height (Fig. 23). The stones are then evenly spaced six‐fingers apart using the index, middle, and ring fingers of each hand placed knuckle side down between each stone (Fig. 24).
Figure 20, 21, 22. Determining the base rock height for different size stoves depending on the pot size. Left: base rock height for a small cooking pot (2‐3kg); Center: base rock height for a medium size pot (4‐6kg); Right: base rock height for a larger size cooking pot (8‐10kg)
Figure 19. The raw materials required
for building the CREATE! stove;
pounded clay, sifted sand, and sifted
millet chaff.
22
Figure 23, 24. Three rocks are cut to the determined height (left) and then evenly spaced six‐fingers apart in a triangle (right).
The pot with a cup of water poured inside is then placed on the stones to check for level
and balance. If the water has accumulated at one side, this indicates that the pot is tilted. The pot or the stones are slightly adjusted until the water is even and level with the base of the pot. Once the pot is balanced and the stones are located in their final place, an outline of the stove is traced a hand’s width distance from the stones, finishing at each end of the stove’s opening. Phase 2: The clay is mixed with the millet chaff, sand, and water to become a more malleable and stronger building material. A bucket of clay is poured out over a plastic tarp or rice sacks, followed by a bucket of millet chaff and a bucket of sand (Fig. 25). All the materials need be thoroughly dry mixed together for best results (Fig. 26). Once the materials are well mixed, water is slowly poured onto the materials and they are mixed again until evenly moist and can be shaped into small compact balls of clay approximately the size of a baseball (Fig. 27, 28). It is important to add just the right amount of water into the mixture. If water is dripping out of the mixture when it is squeezed, it is too wet and needs to dry out or be mixed with drier materials. If the clay balls are not adhesive but crumble apart, more water should be added to the mixture. Once the ideal moisture content is reached, the clay pile is formed into small compact clay balls until the pile is finished (Fig. 29). After the pile has been transformed into clay balls, the process is repeated with the remaining buckets of materials.
Figure 25, 26, 27. An equally proportional amount of materials are poured out onto a tarp (left). The women thoroughly dry mix the materials (center), add water, and mix again until the pile is evenly moist (right).
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Figure 28, 29. Once the clay pile is thoroughly mixed and moistened, the women begin compacting the clay into small balls until they have used all of the materials in the pile.
Phase 3: Before constructing the stove, the outside of the pot should be moistened with water to be easily removed from the stove structure once the clay has been form fitted around it. The clay balls are compressed layer by layer within the outline of the stove marked on the ground until the structure reaches reach a three‐finger width distance from the pot’s handles (Fig. 30). Before handling the clay ball, the builder’s hands should be dipped in water to keep the clay moist resulting in better compaction and adhesion. Compressing the clay should be done with two hands with the top hand pressing down firmly while the other hand works to contain the material within the outlined perimeter of the stove. It is important to level each layer before beginning another layer or else the stove could become lopsided. Two people working at this task, each working on the opposite side and meeting at the center back of the stove, are more efficient and effective than one person.
Once the primary structure is complete, the outside base, or foot, of the stove can be built. It is easier to construct the outside if the clay balls are formed into a more elongated cylindrical shape, approximately 11.5cm in length and 5cm in diameter. After reshaping the clay, an additional hand’s‐width outline for the base is traced around the newly constructed stove. To make the outside base of the stove, only two layers of clay are compacted within the outline and then the structure of stove is finished (Fig. 31).
Figure 30. Two women working at
opposite ends compress the clay balls
into the shape of the stove. They
constantly moisten their hands to
keep the clay wet and malleable. The
cooking pot is also moistened so it is
easier to remove once the stove is
completed.
24
Phase 4: At this point, the basic structure of the stove is complete. However, the sides, top, and base of the stove are crudely shaped and need to be reshaped and neatly smoothed out. Additionally, smoke columns will be cut out from the inside of the stove. This process is done while the clay is still wet using a machete frequently dipped in water to make it easier to create the sharp, smooth cuts around the edges and to carve out the smoke columns (Fig. 32). The outside perimeter of the stove is cut into eight smooth, symmetrical flat faces to form an octagon. The faces begin with two diagonal cuts in the front opening and each sequential face begins at the corner of the previous cut until it forms a corner at the center rear of the stove. The faces are smooth and straight down, not slanting inwards or outwards (Fig. 33). It is important to use a sharp machete frequently dipped in water because the wet blade makes smoother, cleaner, sharper cuts. The foot or the base of the stove is cut to match the faces of the stove. If the cuts slant inwards, more clay can be added, compacted, and smoothed into the face of the stove to even it out. The top of the stove and the top of the base should be smoothed out with the wet machete blade.
Once the octagonal shape is carved out, the pot is slowly removed by slightly twisting it from the stove and gently lifting it out. The smoke columns are cut from two opposite points of the inside diameter of the clay stove. The points are marked and at a two‐finger width from the inside diameter and the wet blade makes a horizontal incision tangent to this diameter. An additional two vertical slices starting from the ground up meet the ends of the horizontal incision and the column of clay is slowly removed. Repeat this process on the opposite side and the clay stove is finished.
Figure 32, 33. A wet machete is used to cut chutes to help improve ventilation (left) and to give the CREATE! stove its distinct octagonal shape (right).
Figure 31.After the primary structure
of the stove is complete, the next step
is to construct the outside base. The
clay balls to make the base are slightly
more elongated than the ones to
construct the main structure of the
stove.
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Phase 5: For four women, a clay stove takes around 2 hours to complete, starting from
mixing the materials and finishing at carving out the smoke columns. There were typically six to eight women in addition to the four women trainers helping with each stove which made the process much more efficient. Once their stoves are completed, it was common for the women in Ndorong Sereer to decorate their stoves and add embellishments such as seashells, colorful rocks, or carving their name and date into the base (Fig. 34). The final step is to sprinkle sand on the stove to encourage the drying process and wait at least two days for the stove to dry completely before cooking its first meal.
Methods
In my study I used quantitative measurements to determine the efficiency of both types of stoves and qualitative methods to gain user perspectives on the advantages, disadvantages, and general opinions regarding each stove. The efficiency of each stove was determined through the boil test and the cook test. These tests are approved by the International Organization of Standards (ISO) as effective methods of determining a stove’s efficiency and are used as a standard to test cook stove efficiency (GACC 2014). The boil test examines the stove’s ability to boil a set amount of water and the cooking test examines the stove’s ability to cook the same meal using a preset amount of ingredients. The boil test is a more direct and uniform method of determining the efficiency of a stove because boiling water is more straightforward than cooking a meal (GACC 2014). People often have different methods and procedures for preparing the same meal and these discrepancies can potentially influence the efficiency of the stove
While the boil test is a more straight forward method, it is not an accurate or realistic representation of the actual cooking conditions in Ndorong Sereer. Very few people just boil water, and if they do, they use a lid. To make this test represent a more realistic situation, the amount of water boiled was an estimated equivalent of the amount used to cook 2kg of rice, which is the typical amount of rice cooked for lunch for a family of seven people. Additionally, rather than using the local boiling point based on location and elevation, the boiling point was decided by the women as the point when they would add the rice to the water, which was determined to be 96⁰C.
Figure 34. Women
decorating a
recently completed
CREATE! stove with
seashells .
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The Water Boil Test (WBT) The fuel efficiency of the clay cook stove and the three‐stone stove was measured using
two distinct tests; the boil test and the cook test. For the boil test, five women were chosen to conduct five boil tests on the clay stove and five boil tests on the traditional three‐stone stove. The women were specifically chosen because they have been cooking regularly with their clay stove for over six months and each had built a clay stove for a 4kg pot. Each test heated 3.095kg of water to a temperature of 96⁰C. The amount of water was based on an informed estimate on the amount of water used to cook 2kg of rice. The temperature of 96⁰C brought the water to a vigorous boil declared by multiple women to be the appropriate temperature to add rice to the water. To eliminate the possibility of different species of wood contributing to varied cooking times, all of the firewood used for both the boil test and the cooking test were the same species, Acacia seyal, that had been air dried for over a month.
The WBT can reveal a variety of indicators relating to a stove’s performance. I used the WBT to measure the boil time, specific fuel consumption, and thermal efficiency of both stoves. Specific fuel consumption can be used for a range of cooking tasks as it is the ratio of fuel required to produce a unit output, which in this case is the amount of fuel (g) required to boil 3.095 kg of water (van der Plas 2009, Bailis et al. 2007). Thermal efficiency as defined by Ballard‐Tremeer (1996) is the ratio of energy entering into the cooking pot to the energy content of the firewood consumed. As energy from the fire heats the pot, it raises the water temperature to boiling point and evaporates water. Therefore, thermal efficiency can be determined by measuring the change in water temperature, the amount of water evaporated, and the amount of wood used to reach boiling point. I calculated thermal efficiency according to:
∆
where is thermal efficiency expressed as a fraction; is the specific heat of water which is
4.186 kJ/kg C⁰; is the mass of water boiled (kg), ∆ is the change in temperature from the initial recorded temperature to boiling point (C⁰); is the latent heat of evaporation of water
which is 2,260 kJ/kg; is the mass of water evaporated (kg); is the mass of firewood used
(kg); is the calorific value of species‐specific wood fuel (kcal/kg); is the mass of remaining
charcoal (kg); and is the calorific value of species specific charcoal (Ballard‐Tremeer 1996, Bailis et al. 2007). The calorific value of the firewood and charcoal of Acacia seyal, was determined to be 4,579 kcal/kg and 6,590 kcal/kg, respectively (El‐Juhani 1996).
In addition to measuring the time to boil, I also recorded the number of pieces of wood, initial weight of wood, final weight of wood, charcoal weight, final weight of wood combined with the charcoal weight, and the total weight used. The total weight used was determined by subtracting the final combined weight of wood and charcoal from the initial weight of wood. Additional recorded data included the stove dimensions, pot dimensions, weight of the pot,
27
initial weight of water, final weight of water, initial temperature of water, final temperature of water, amount of water evaporated, type of tinder, and tinder weight.
The water temperature was recorded using a mercury cooking thermometer and the weight of the wood was taken using a suspended baby scale and a portable digitized scale. The initial weight of wood was too bulky to balance on the digitized scale and was thus tied into a bundle and weighed from the suspended baby scale. The final weight of wood and charcoal were weighed on a tared platter atop the digitized scale. The water weight was measured using the digitized scale in a tared 1.5L measuring cup.
For each boil test, the women provided firewood and tinder that they selected themselves as an appropriate amount for the test. The women also provided a large bucket of water which was kept indoors to maintain a consistent temperature throughout the day of testing. Once the wood and water were weighed, for each test the women prepared the firewood and the tinder beneath the stove and ignited the tinder with a match. The pot was placed in the stove once the branch and trunk pieces had caught fire and the thermometer was clipped to the inside of the pot with the tip submerged in the water. Measurements of the temperature were recorded every minute until the temperature reached 96⁰C. Once the boiling point was reached, the pot was taken off the stove and the wood and charcoal were immediately removed and extinguished with sand. Extinguishing the burning wood and charcoal with sand was preferred to water because the wood and charcoal would absorb the water affecting their weight. The remaining water was weighed as well as the extinguished wood and charcoal once they were cool enough to handle.
The boil tests conducted on the three‐rock stove followed the same procedure. The same pot used in the clay stove boil tests was used for the three‐rock stove boil tests. Five boil tests took a day to complete. Each of the five women conducted 5 boil tests on the clay stove and five boil tests on the three‐rock stove. There were a total of 25 boil tests conducted for the clay stove and a total of 25 boil tests for the rock stove, a total of 50 boil tests. This study analyzes the results obtained from those 50 boil tests. The Controlled Cook Test
The cook test is an alternate method to test the stove’s efficiency by measuring the time and amount of wood needed to cook a meal with a predetermined amount of ingredients (GACC 2014). The cook test can provide a more accurate representation of the amount of wood used for realistic cooking practices (GACC 2014, Bailis et al. 2007). However, while conducting the cook test, it can be difficult to keep variables constant, as the weight of ingredients and cooking procedures which can affect the measurement of the stove efficiency. For example, cooking with different varieties of rice can affect the overall cooking time based on variety’s ability to absorb water. Each cook test used the same ingredients and the same amount of ingredients because variations to either can affect cooking time. Differences in cooking procedure can be managed by ensuring the same participant cooks the same meal multiple times.
I identified five different women to conduct the cook test on their clay cook stove and three‐rock stove. The women were chosen because each of them had a clay stove that could support a 4kg pot, cooked for a similar number of people every day, and had more than six
28
months experience cooking with their clay cook stove. The national dish of Senegal, ceeb u jen, was chosen as the meal cooked for each cook test (Fig. 35). The meal is a popular lunch dish throughout all of Senegal and the women of Ndorong Sereer are very familiar with cooking it, often having it for lunch multiple times per week. The ingredients of Ceeb u jen are rice, fish, vegetables, seasoning, and cooking oil. The final list of ingredients and their quantities were decided through collaboration with the five women. Before each test, the ingredients were purchased from the same supplier and weighed on a digitized scale. The specific ingredients, quantities, and recipe are listed in Table 1.
The cooking test measured similar variables as the boil test. In addition to recording the weight of ingredients, data was recorded regarding the number of pieces of wood used, the initial weight of wood, the final weight of wood, the charcoal weight, the final weight of wood with the charcoal, and the weight of wood used. For each test, the women selected how much firewood to use. The initial wood weight was taken using a suspended baby scale because the pieces were often too large to measure on the digitized scale. The final weight of the wood and the charcoal were taken on the digitized scale because they were able to fit on a tared platter. Measurements of the stove dimensions, pot dimensions, and the weight of the pot were also recorded. The cooking time was recorded with a stopwatch and began when the pot was placed in the stove and the end of the test occurred when the women removed the pot from the stove to stop cooking.
After all the wood and ingredients were weighed, for each test the women selected the firewood, set up the wood inside the stove, added the tinder, and ignited the tinder using a match. The women prepared and cooked the meal with all of the provided ingredients and their cooking time was recorded. Once the cooking was completed, the firewood and charcoal were extinguished with sand and measured when they were cool enough to handle. One cooking test was conducted per day per woman. Four of the five women performed one cooking test on the clay cook stove and one cooking test on the three‐stone stove and one of the women performed two cooking tests on the clay cook stove and one cook test on the traditional stove. A total of six tests were conducted on improved clay cook stoves and five tests conducted on the traditional three‐stone stoves. Unfortunately, this study was able to only conduct a total of 11 cook tests for five different participants. Nonetheless, the data that was collected still provides a good estimate of the cooking efficiency of each stove.
Table 1. List of Ingredients, Weight, and Recipe for Ceeb u jen
Ingredients Cost (cfa) Mean Ingredient Weight (kg)
Recipe
Rice 520 2.15 Heat oil in pot, once sizzling add fish and onions, garlic, green pepper, cook for ~10min
Add ~4.5L of water, followed by veggies and seasoning
Steam 2kg rice for ~10 min.
Fish 400 1.09
Oil 375 0.372
Vegetables (Carrot, Cabbage, Eggplant, Tomato, Bitter
400 0.85
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Tomato, Green Pepper, Hot Pepper)
on top of cooking pot
Remove fish and veggies, add rice to boiling water
Let rice cook for~15min, once rice is soft, remove pot from fire
Scoop rice into lunch bowl, add fish and vegetables
Onions + Garlic 25 0.203
Salt ‐ .045
Seasoning 100 0.059
Statistical Analysis
Water Boil Test (WBT)
Response variables were checked for normality using values of skewness and kurtosis. Non‐normal variables were transformed using log10 to normalize the distribution. I conducted a one tailed, two sample t‐test on the response variables boil time, fuel wood use, specific consumption, and thermal efficiency to test the null hypothesis that the improved CREATE! stove was less efficient or as efficient as a the 3‐stone stove. When conducting the WBT, each participant used their own pots for both stoves and the same pot that was used in the boil test was also used in the cook test. It was found that the pot weight did not have a significant effect on boil time in an analysis of variance (F=1.21, df=1,38, p=0.28). Statistical analyses were conducted in SAS (SAS Institute 1999).
Controlled Cook Test (CCT)
Response variables from this test were also checked for normality using values of skewness and kurtosis. All variables were shown not to violate the assumption of normality. I
Figure 35. The Senegalese national
dish Ceeb u jen. During lunch, it is
common practice for the entire family
to sit together and eat from the same
bowl. The amount purchased for the
CCT was enough to feed a typical
family of seven and to send a lunch
bowl to relatives in another
compound.
30
conducted a one tailed, two sample t‐test on the response variable cook time to determine significant differences in wood use and specific consumption between the CREATE! stove and the 3‐stone stove. In this test, there was no significant differences in food weight between the CREATE! stove and traditional stove, which could have induced a bias in the results, (t(9) = 0.6, p = .056). Interview Methods
Gaining user perspective on a new technology is critical to understanding if it is effective and appropriate for the community. Interviews are one of the best ways of gaining a wide range of unique perspectives and opinions about a new technology. For this study, I conducted 15 interviews with women from Ndorong Sereer discussing the perceived advantages, disadvantages, and general experience cooking with different types of wood stoves. The interviews were semi‐structured with primarily open‐ended questions encouraging the participant to express their individual opinion about what was most relevant to them. Their responses can reveal if the improved clay stove is actually a sustainable option over the traditional three‐stone stove, if its benefits and impacts are fully realized, if certain design aspects have been overlooked and what improvements can be made. Additionally, the women’s responses provide valuable feedback critical to understanding how and why the improved stove was so readily adopted and disseminated when so many other improved cook stove programs around the world have failed.
The interview questions were developed based on a literature review, namely Barnes (1994) and Soini and Coe (2014), of the conditions and factors that influence a community’s willingness to adopt and disseminate a new cook stove. After developing the questions, I had help translating them into Sereer by several native speakers to help clarify and convey the intended meaning of the question. Once the questions were developed, they were reviewed by the University of Washington Human Subjects Division and granted exemption under Category 2 (Exemption #49101). I was permitted to use all of the questions while conducting the interviews under the condition that I inform the interviewees about the purpose of the interview, that their responses would be recorded and potentially read by others, that their responses would remain anonymous, and that in no way would I associate their identity with their answers. All 15 respondents agreed to these terms before the interviews were conducted.
The interviews were conducted in Sereer and recorded with a tape recorder with the participants’ consent. The majority of the interviews were conducted in the interviewee’s compound with other people present. I felt the informal setting set a relaxed tone to the interviews which prompted more authentic answers and made the interviewees feel more at ease to discuss their experiences at length. The interviews typically lasted between 10 to 20 minutes and the women received no payment or reward for their participation. All of the interviewees had been using the improved clay cook stove for over six months. To try to obtain more robust perspectives on cooking experiences, I decided to interview women from different age groups who cooked for different sized families. The interviewees were between 20 – 55 years of age and cooked for families ranging from 5 to 12 people.
All of the women interviewed were from the village of Ndorong Sereer and knew me very well since I had been living and working in the community for nearly two years. It is unclear
31
whether this relationship could have caused any significant bias in their responses. Prior to the interviews, I had worked very closely with many of the women on agricultural projects and they knew I was very concerned about deforestation and motivated to plant more trees. They were also aware that I helped introduce the stoves to the village. It is possible this could have caused them to exaggerate wood reductions from using the clay cook stoves or other advantages in order to please me. However, based on numerous responses from multiple interviewees that reported very similar amounts of wood use, numerous responses detailing very similar experiences using both stoves, and personal observation of wood use from conducting the efficiency tests, I conclude that this bias, if there was one, does not significantly affect the validity of their responses. Furthermore, if the women were just exaggerating the benefits of the clay cook stove, they would not be consistently and constantly using the clay stove for all of their meals as they are doing now.
The recorded interviews were translated and transcribed from the Sereer by myself,
who tested as an Advanced‐Low Sereer speaker according to the Language Proficiency Index
(LPI). The responses did not contain any unfamiliar words or phrases, however, there were
certain descriptions which could not be translated literally into English. In such cases, the
passage was subjectively interpreted to the best of my ability to faithfully convey the intended
message of the respondent. The interviews were transcribed into Microsoft Word documents
for qualitative analysis. After transcribing the interviews, I conducted the data analysis by
rereading the interviews to search for emerging themes and patterns in the responses. Similar
responses among interviewees were grouped together and assigned a code to summarize the
relevant message of the quote. The initial codes were narrowly focused on specific words or
phrases, however, they were gradually revised to encompass broader themes and subsequently
included more quotes from multiple respondents. The final codes captured numerous
responses related to experiences with the different stoves’ fuel efficiency, safety, smoke
emissions, durability, convenience, and experience with past cook stoves.
ResultsandDiscussion
The Water Boil Test (WBT)
The data suggested that the CREATE! stove is more thermally efficient and boiled water
faster than the traditional 3‐stone stove using a similar amount of wood. Results for the boil
time, fuel use, thermal efficiency, and specific consumption of both stoves are listed in Table 2.
Table 2. WBT Results for the CREATE! stove and the 3‐stone stove.
Stove Type Boil Time (Min) Fuel Use (kg) Thermal Efficiency (%)
Specific Consumption (g/kg)
CREATE! 14.03 0.782 36% 253
3‐Stone 17.36 0.8544 23% 276
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In terms of boil time, I observed significant differences in boil time depending on the
stove type (t(38) = 2.02, p<0.025). The CREATE! stove required 21.22% less time to boil water
than the traditional cook stove. The mean (±SE) boil time for the improved cook stove was
14.03 (1.13) min and the mean (±SE) of the traditional stove 17.36 (1.20) min (Fig. 36). These
values exclude data points recorded from the first trial of each participant because there was a
significant difference between these trials and the subsequent trials apparently due to a
“learning‐curve” of conducting the boil test (ANOVA F=4.5, df=4,45, P=0.0022). Each participant
experienced this “learning‐curve” with their first trial regardless of the stove used. While this
may be due to the first tests beginning from a ‘cold‐start’, it is more likely a result of the
unfamiliarity with the task, as boiling water is not a common daily activity, and
misunderstanding the purpose of the test. The mean (±SE) boil time for the first trial, regardless
of the type of stove, was 25.25 (2.40) minutes while the mean boil time for the subsequent
trials regardless of the stove type was 15.7 (1.10) minutes. Excluding the first trial did not alter
the conclusion of the results and the improved cook stove was still found to require significantly
less time to boil water than the traditional cook stove.
Figure 36. The chart shows that there is a significant difference in mean boil time between the two
stoves. The improved clay stove required significantly less time by approximately 3.5 minutes to boil
water than the traditional three‐stone stove.
In terms of thermal efficiency, the CREATE! stove was found to be significantly more
efficient than the 3‐stone stove, (t(48) = 1.923, p<0.03). This indicates that the CREATE! stove is
more efficient than the 3‐stone stove at transferring heat from the fire to the cooking pot,
which is most likely due to the CREATE! stove’s design. Because it has clay walls which surround
the cooking pot, the CREATE! stove is more effective at containing, insulating, and transferring
the heat to the cooking pot. The mean percent (±SE) of thermal efficiency for the CREATE! stove
14.03
17.36
0
2
4
6
8
10
12
14
16
18
20
CREATE! 3‐stone
Boil Time (min)
Stove Type
Stove Comparison of Mean Boil Time
33
was 36% (0.06) and 23% (0.017) for the traditional 3‐stone stove. While the CREATE! stove was
found to be more thermally efficient, it did not significantly outperform the 3‐stone stove in
terms of specific consumption (t(48) = .98, p < .836). The CREATE! stove required 253 (.0811) g
of wood to heat 3.095 kg of water while the 3‐stone stove required slightly more wood, 276
(.0871) g, to heat the same amount of water.
Although the mean weight of wood used to boil water was slightly less for the CREATE!
stove than for the traditional 3‐stone stove, there was no significant difference between the
stove type and amount of wood used, (t(38) = 0.01, p = 0.99).
Figure 37. Scatter Plot graph displays that there were no significant correlations between the
weight of wood used and boil time between the improved clay stove and the traditional stove. However,
there were significantly different mean boil times between the stoves, which suggest that while using a
similar amount of wood, the CREATE! stove can boil water faster.
This finding indicates that while both stoves used a similar amount of wood for the
WBT, the CREATE! stove was able to transfer the heat of that wood more efficiently resulting in
reduced boil times. The complex relationship among wood use, boil time, stove type, and
participant is illustrated in Figure 38.
0
5
10
15
20
25
30
35
40
0 0.5 1 1.5 2
Boil Time (min)
Weight of Wood Used (kg)
Stove Comparison of Wood Use and Boil Time for the Water Boil Test
3‐Stone Stove
CREATE! Stove
34
Figure 38. Graph comparing the mean boil time and wood weight used per participant.
Participant 1 is the only participant who uses more wood for the CREATE! stove than for
the traditional stove, however, the reduced boil time from the CREATE! stove was not as
pronounced as it was for other participants. For the traditional stove, Participant 1 used a
similar amount of wood as Participant 4, however, Participant 1’s traditional stove reached
boiling point 5 min. faster than those of Participant’s 3 and 4. Furthermore, Participant 1 uses a
similar amount of wood for the CREATE! stove and achieves similar boil times as Participants 2
and 5. It is unclear what made Participant 1’s traditional stove outperform the others.
Participant 2 had the largest difference in boil time, approximately 7 minutes faster, when using
the improved stove and also used 0.215 kg less wood than the traditional stove. An interesting
observation is that out of all the participants, Participant 2 used the most amount of wood for
the traditional stove and still had one of the longest boil times. Participant 3 experienced
similar boil times between the two stoves, however the participant used only 0.678 kg of wood
for the improved stove and used 0.941 kg of wood for the traditional stove. Participant 4 used
the least amount of wood for the CREATE! stove than any other participant and was able to boil
water 4 minutes quicker on the CREATE! stove than the traditional stove. Finally, Participant 5
had the fastest average boil time (11 min) of all the participants for both stoves. Also, the boil
time was nearly the exact same for both stoves and the CREATE! stove used only slightly less
wood, 0.105 kg, than the traditional stove. These minimal savings may be partly due to the fact
that during the WBT for the traditional 3‐stone stove, this participant boiled water outside in an
area completely exposed to the sun and heat, whereas the other participants boiled water on
0
0.2
0.4
0.6
0.8
1
1.2
0
5
10
15
20
25Traditional
Improved
Traditional
Improved
Traditional
Improved
Traditional
Improved
Traditional
Improved
P1 P2 P3 P4 P5
Mean
Weight of Wood Used (kg)
Mean
Boil Time (min)
Participants and Stove Type
Stove Comparison of Mean Wood Weight Used and Boil Time by Participant
35
traditional stoves inside a kitchen hut, which provided shade and cooler temperatures. This
participant did not have enough room in her kitchen hut which was occupied by two CREATE!
stoves, therefore she cooked outside where the afternoon sun and heat could have contributed
to faster boil times for the traditional stove.
While the performance of the 3‐stone stove is highly dependent on the operator (Jetter
and Kariher 2009), there was no significant interaction between participants and the stove
type, (F = 1.00, df=4,45 p = 0.42). Conversely, there was a significant difference among the
participants cooking speed, (F = 4.52, df=4,45, p = 0.006), meaning that each participant cooked
either faster or slower from one another based on individual cooking style, regardless of stove
type. These findings help negate the presence of the “Hawthorne effect” in the data, which
occurs when participants change behavior because they are aware of being watched and
recorded.
Unfortunately, this study was not able to perform the simmer test in addition to the boil
test. In the simmer test, the cook brings the water to a vigorous boil and then lowers the heat
to a low boil or a simmer for at least 45 minutes, which enacts cooking tasks like preparing
beans or rice. In the context of this study, the simmer test would have used too much fuel
wood and presented no real benefit for the cook since villagers have no need for boiled water.
This test could have provided evidence of greater wood reductions and thermal efficiency.
However, it is not unusual to see mixed results and weaker percentages of efficiency through
conducting the WBT. In several different studies, the traditional stove was just as efficient or
even more efficient than several different types of improved cook stoves when using the WBT
(Bailis 2007, Donee 2012, Vaccari et al. 2012, Jetter and Kariher 2009). Furthermore, it is widely
acknowledged that The Controlled Cook Test provides a better opportunity to assess the degree
of a stove’s efficiency and its ability to perform under realistic cooking conditions.
The Controlled Cook Test (CCT)
Overall, the CREATE! stove significantly outperformed the traditional 3‐stone stove in
wood savings, using 33% less wood to cook Ceeb u jen, however there was only a slight
difference in mean cooking time between the two stoves. Food weight was standardized for
both tests, therefore it did not have a significant effect on wood use in the stoves, (t(9) = 0.6, p
< 0.56). Results from the CCT for both stoves are reported in Table 3.
Table 3. Controlled Cook Test Mean Weight of Wood Used and Specific Consumption per Stove
Stove Type Number of trials
Mean Weight of Wood Used (kg)
Mean Food Weight (kg)
Mean Specific Consumption (g/kg)
Mean Time to Cook (min)
CREATE! 6 2.3405 4.62 507 90
3‐stone 5 3.4972 4.57 763 87
36
After performing a one‐tailed two sample t‐test, it was found that the improved cook
stove used significantly less wood than the traditional cook stove, (t(9) =3.66, p < .003). For the
CREATE! stove, the mean (±SE) weight of wood used was 2.3405 (0.075) kg and mean weight of
wood used for the traditional 3‐stone stove was 3.5 (0.338) kg (Fig. 39). The CREATE! stove used
33% less wood to prepare Ceeb u jen than the traditional three‐stone stove. The wood savings
from the CCT are more substantial than those from the WBT because of the extended duration
of the test. The CCT provided the opportunity for the CREATE! stove to exhibit its capacity to
contain and concentrate more heat to the cooking pot and also protect the fire from the wind.
The positive effects of insulation and wind protection help improve the CREATE! stove’s
efficiency and are not as pronounced during the WBT because the tests take significantly less
time.
Figure 39. Graph displaying comparisons of the mean weight of wood used for the Controlled Cook
Test. The CREATE! stove used significantly less wood than the 3‐stone stove for the CCT.
In addition to using significantly less fuel wood, there was a significant difference in the
specific consumption between the two stoves, (t(9) = 4.113, p < 0.0013). The CREATE! stove had
a significantly lower mean specific consumption, 507 (0.018) g/kg, than the mean specific
consumption of the traditional stove, 763 (0.065) g/kg (Fig. 40). This indicates that the CREATE!
cook stove used 256 g of wood less than the traditional stove in order to cook 4.62 kg of food.
2.3405
3.4972
0
0.5
1
1.5
2
2.5
3
3.5
4
CREATE! 3‐stone
Weight of Wood (kg)
Stove Type
CCT Stove Comparison of Mean Wood Use
37
Figure 40. Graph displays the mean specific consumption for the CREATE! stove and 3‐stone stove for
the Controlled Cook Test. The CREATE! stove exhibits a lower specific consumption than the 3‐stone
stove which shows that it requires less wood than the 3‐stone stove to cook an equal amount of food.
The CCT has been regarded as a more authentic representation of a stove’s
performance in efficiency and adaptability because it is tested under conditions using
traditional foods, cooking practices, and local fuels (Bailis 2007, van der Plas 2009, Vaccari et al.
2012). The results from the CCT indicate that the CREATE! stove surpasses the performance of
the traditional stove in wood savings. If this study had been able to include more CCT’s, it could
have provided stronger evidence supporting wood reduction and efficiency for the CREATE!
stove. This study was able to collect data for 11 CCT’s for five different participants, but due to
social pressures in village, I had to cease conducting CCT’s. Many villagers did not understand
the nature of the tests and became resentful that I was purchasing lunch every day for only five
families. In Senegal, lunch is a very important aspect of the culture and daily life. It is often the
most expensive meal which has the most food available and where everyone eats together.
Many people in village felt that I preferred these five participants over them, and this could
have potentially jeopardized my working relationship with them as a Peace Corps Volunteer.
This was an unforeseen barrier and should be noted as a possible barrier for future stove
testing conducted in Senegal.
Interview Results and Analysis
The interviewee’s responses provided valuable feedback and perspective about their
experiences using the improved and traditional cook stoves. The interview questions were
507
763
0
100
200
300
400
500
600
700
800
900
CREATE! 3‐stone
Specific consumption (g/kg)
Stove Type
CCT Stove Comparison of Mean Specific Consumption
38
informed by a literature review of important issues previously identified as influencing a
community’s acceptance, adoption, and dissemination of a new cook stove. The women were
asked questions pertaining to the stoves’ efficiency, safety, smoke emissions, design,
cleanliness, convenience, and past experiences with different clay stove models. The open‐
ended questions were intended to be exploratory in order to gather a wide range of user
perspectives to assess the CREATE! stove’s integration into the community. The following
results include coded responses from 15 women with over six months experience cooking with
the improved clay stove.
All of the women interviewed clearly stated that they preferred using the improved clay
stove and were eager to describe its advantages over the traditional stove. When asked what
they preferred about the clay stove, the most common response was its efficiency; the clay
stove required less wood and cooked faster than the traditional stove.
“The clay stove is better. The clay stove is faster. Only three pieces of wood can
cook a meal. You only need small branches. You can use only two pieces of trunk
pieces and then a small branch. If it’s the rock stove, you need two pieces of
firewood for each opening until you have six pieces”
The women acknowledged that they used significantly less wood and smaller pieces of wood
with the clay stove and that it cooked faster than the traditional stove. Smaller pieces of
firewood are easier for the women to collect and can perform just as well in the clay stove as a
large piece of wood in the traditional stove. When asked why the traditional stove isn’t as
efficient, the majority of women identified the wind as the primary issue.
“The clay stove only has one opening, so there is little wind. The wind can’t get in
like the rock stove. If it’s the rock stove, the wind passes through each opening
and makes the fire burn the wood quickly. It makes the wood finish very quickly.”
The women typically cook in a drafty millet‐stalk hut that offers little protection from the wind.
The open layout of the traditional stove exposes the fire to the wind which diffuses heat away
from the pot. The fanned flames might be larger, but since the heat is dispersed, more time and
wood are needed to cook the meal. Alternatively, the clay walls of the improved stove protect
the fire from the wind and keep the fire contained which concentrates heat onto the pot.
“The clay becomes hot in itself and its more than just two pieces of wood. When
it heats up, it’s like cooking with the same amount of firewood as the rock stove”
The clay walls capture heat so effectively that one respondent observed that cooking with two
pieces of wood is like cooking with six pieces for the rock stove. The clay walls act as insulation,
trapping the heat, which enables the stove to remain hot even after the firewood is removed.
39
Several women mentioned that the hot clay walls help cook faster and they often cook with just
leftover charcoal after heating up their stove.
“Just the heat from that, you can take the firewood out and leave the charcoal
inside, it will cook until finished”
It is apparent that the women recognize a significant difference between the performance of
the improved clay stove and the traditional stove. Their perceptions of reductions in fuel and
cooking time align with the results found in the efficiency tests conducted on both stoves. To
further corroborate these results, the women were asked about the number of wood pieces
needed to cook a meal for each stove and the type of wood used. All of the women had very
similar responses when asked about cooking with the clay stove, stating they only used two to
three pieces of wood to cook each meal.
“I use two pieces of trunk pieces and one small branch between them.”
“If you have two or three pieces of firewood, it takes no time cook, the water
boils very quickly.”
“If it is the clay stove, you only put it in one opening. You can use only one trunk
piece and break up smaller branches and it will be very quick.”
The firewood was typically one or two split trunk pieces and one broken up branch. When
cooking with the clay stove, the women preferred using smaller wood pieces and it was
mentioned several times that a meal could be cooked from just branch pieces, which is not a
feasible option for a traditional stove. The branches are widely regarded as easier to find and
lighter than other types of firewood, which can make firewood collection a less strenuous task.
When asked about the traditional stove, the women all agreed that it requires more wood.
Based on their responses, the traditional stove required six to nine pieces of wood to cook a
meal, many of which were larger trunk pieces.
“If it’s the rock stove, you need two pieces of firewood for each opening until you
have six pieces.”
“For the rock stove you have to use many pieces. You put three pieces here, three
here, and three here. Each opening will have three pieces so the fire will burn
well.”
“The rock stove can’t cook with the small pieces. You are using only the big trunk
pieces for the fire… then the firewood is gone and you won’t even be finished
cooking. It doesn’t save wood. When you are finished cooking all of the firewood
is gone.”
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The traditional stove needs to have wood in each of its three openings to produce a larger
flame and to maintain an even heat while cooking. Larger and longer pieces are preferred
because they produce bigger flames and are easier to adjust than smaller pieces whose ends
are closer to the flames. For the traditional stoves, women use the branch pieces to help start
and stoke the fire, however as previously mentioned, they are not able to cook a meal with the
branch pieces alone. Based on the responses, the improved stove uses approximately one‐third
of the wood pieces used by traditional stove. These reductions are significantly greater than
those found in the efficiency tests because they are based on the number of wood pieces
rather than the wood weight. However, these observations provide valid and valuable
observations on wood reduction and the women recognize the impact these reductions have
made on their fuel wood collection schedule.
When collecting firewood, women venture out into the forest and bring back a bundle
of wood which can last for a certain number of days depending on the size of the bundle. In
order to find a baseline for previous harvesting habits, the women were asked about the
number of days a bundle of wood lasted when cooking with the traditional stove. Many of the
respondents noted that it depended on the size of the bundle, but in general a bundle of wood
lasted them two to three days when cooking three meals a day with the traditional stove.
“For one bundle, you will cook for two days until it is entirely finished.”
“If it’s the rock stove you are going to put firewood here, here, and here. It will last only two or three days”
“For the rock stove, one bundle could cook for two days only until it was completely gone. Two days. It makes breakfast, lunch, and dinner two times because I am putting in a lot of wood.”
The women were harvesting firewood every two to three days when they were cooking
with the traditional stove and they were harvesting larger pieces which are more convenient to
use, but more difficult to harvest and transport back to their compound. In order to discern if
the wood use reductions achieved by using the clay stove had any effect on their harvesting
schedule, the interviewees were asked how many days their bundle lasted them when they
cooked with the improved clay stove. All of the women reported that the wood bundle could
be used for a greater number of days relative to the traditional stove.
“The clay stove can have four days or five days. The last time I brought back a
bundle, it was five days until it ran out of firewood”
“If it’s me that harvested the wood and who is cooking, it can last a long time, it
can last a week.”
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“It can last for a long time. The clay stove is very good. Even if the bundle is not
very big, you can still cook for five days. You will cook breakfast, lunch, and
dinner. With the one bundle you can cook that much. The clay stove is very
important.”
When cooking with the clay cook stove, women can harvest firewood every four to five days,
sometimes even once a week, instead of every two to three days. The wood use reductions
from using the clay stove are sufficient to reduce the frequency of their wood collection
schedule, giving women a few extra days free of the arduous chore of wood collection as well
as easing the intensity of wood extraction from the forest. Since every household in Ndorong
Sereer now has an improved cook stove, this implies significant reductions in the amount of
fuel wood extracted from the Djilor forest as well as less time and effort expended by the
women harvesting fuel wood.
“It [the clay stove] has helped the lives of all the women. If you have it [the clay
stove] in your compound, you are very happy. Harvesting is no longer difficult.
We are very tired already, we go into the forest and chop down firewood until we
are even more tired. You use the wood in the rock stove and all of that firewood
is gone.”
The clay stove is clearly recognized for its ability to cook faster, use less wood, and
reduce the drudgery of harvesting by extending the time between harvests and is capable of
cooking with branches which are easier to collect. However, fuel efficiency and easing daily
chores aren’t the only advantages the women notice about the clay stove.
In addition to these elements, the women appreciate the clay stove because they find it
safer to use than the traditional stove. When asked about safety, the most talked about cooking
hazard was kitchen fires. Since the kitchen huts are typically constructed with highly flammable
materials like dried millet‐stalk and weeds (it is common practice for women to use bits of their
kitchen walls and roof as tinder), a stray flame or piece of charcoal can easily set the hut on fire.
During my service, two separate kitchens in the village caught fire on the same windy day and
ended up igniting several other huts in the compound. The women, who were cooking
breakfast with the traditional stove, had just stepped outside of the kitchen when a strong wind
passed through and swept up a hot piece of charcoal which landed near the kitchen wall,
setting the hut on fire. Unfortunately, kitchen fires are a fairly common occurrence and are
often devastating for the family and the village. During several interviews, women revealed that
past kitchen fires had set their entire compound on fire and moved onto the neighbor’s
compound. Since there is no running water or reliable fire‐fighting system, water must be
pulled from the nearest well, bucket by bucket, until the fire is extinguished.
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When asked about stove safety, all of the women identified the clay cook stove as safer
to cook with because of its ability to prevent kitchen fires. The walls of the clay stove protect
the fire from the wind, keeping the flames, charcoal and ash contained within the stove. When
the wind comes, the ash and charcoal cannot be swept up by the wind, which frequently
happens with the traditional stove because the fire is exposed.
“The clay cook stove. That is safer. Because today you have twirling wind, if you
are cooking in a millet‐stalk wall kitchen, when the wind comes, the clay is what
is protecting it, it will not burn the millet‐stalk wall, the compound will not burn
down. You will finish cooking and your house will not burn down.”
“You can start a fire and come and go. You can go to the store on the other side
of village and you won’t have one problem [with the clay stove]. But if it is the
rock stove, if you have something nearby, it can catch on fire.”
“The wind, if it comes when you are cooking with the clay stove, there is no place
for it to pass through. The fire can’t burn anything. The clay stove is safer. If it is
the rock stove, the wind brings the charcoal and fire to burn. The clay stove is
safer than the rock stove because it blocks the wind from taking the fire.”
There was resounding agreement among the women that the clay stove is safer at preventing
kitchen fires caused by wind scattered flame or charcoal. The wind swept charcoal is not only
responsible for kitchen fires, but several women also mentioned that they or their children are
often burned by the wind scattered ash and pieces of charcoal when moving around the
kitchen.
“When my kid comes in and walks in with bare feet, she steps on the charcoal
and it burns her. You know that is no good.”
“When you would cook in the kitchen with the rock stove, something would
always burn. If you weren’t wearing shoes, you would burn your feet. Now people
won’t get burned in their kitchens. Back then if you looked at women’s shoes,
they would be burned until nothing was left. They would say ‘It’s the charcoal!’”
The exposed fire of the traditional stove is easily susceptible to the wind, not only making it
more inefficient but also a safety hazard for women and their families. Furthermore, while
much less severe than a hut igniting or a burnt foot, the women always brought up the fact that
cooking with the traditional stove dirtied their kitchens because of the windblown ash.
Whenever the wind passed through or when they fanned the flames, the ashes rose up and
covered everything in the kitchen.
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“The clay stove doesn’t have ash. The ash never leaves the stove into the kitchen.
If the clay stove builds up ash, you just pile it up and toss it outside. But with the
rock stove, all of the ash leaves the stove and gets the kitchen dirty.”
“If it is the rock stove, when you fan, the ash will leave and the kitchen will be
very dirty. But if it is the clay stove, when you fan it, the ash will not leave. It is
only inside the stove.”
Although the women only regarded the ash as a nuisance which coated their kitchens, they
were entirely unaware of the more serious threat; increasing their exposure to harmful
particulate matter contained in the smoke and ash. These particulates have been found to
increase the likelihood of contracting pneumonia and other respiratory diseases which they
exposed themselves and their families to with every time they fanned the flames when cooking
with the traditional stove. The design of the improved stove contains all of the charcoal and ash
within the clay walls, preventing ash from escaping the stove when adjusting the firewood and
fanning the fire. This can significantly reduce women and children’s exposure to harmful
particulates and also makes it easier to clean up after cooking.
One of the most important factors in an improved stove is its ability to reduce smoke
emissions. The design of the CREATE! clay cook stove includes smoke chutes cut into the sides
that are designed to reduce smoke emissions by encouraging ventilation and air flow to allow
for more efficient combustion. However, it is unclear whether this design feature actually
reduces smoke emissions (Fig. 41). While this study does not quantify the amount of smoke
emitted from either the traditional cook stove or the improved cook stove, it explored the
women’s perspectives concerning smoke emissions from their experience in cooking with both
stoves. There were mixed responses among the women when asked to relay their experiences
with smoke emissions when cooking with both stoves.
“The clay cook stove has more smoke.”
“The clay stove doesn’t have smoke. The rock stove has more smoke.”
“Both stoves have smoke, but they are different.”
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More than half the women responded that the clay stove produced less smoke, but
there were a number of women who felt that it produced as much if not more smoke than the
traditional stove during certain times of the cooking process or under certain conditions.
“The clay cook stove has smoke. The first time you ignite it, it will have smoke.
But once the fire catches, the smoke is gone. It won’t have smoke again.”
“The clay stove will have smoke whenever you are starting to light the fire. If you
start the fire and it doesn’t light well inside, it will smoke very much.”
The ignition process was identified as the time when the clay stove produces the most smoke.
During the cooking efficiency tests, I also observed this trend of heavy smokiness just as the fire
was being lit which lasted until the bigger pieces of wood had caught fire. An additional
observation was that smokiness was influenced by the wood pyramid or fuel structure built
inside the stove to help the fuel wood catch fire. If the structure was built properly, the fuel
wood would quickly ignite and there would be little smoke, however, if the structure was built
Figure 41. The CREATE! stove
producing smoke at the beginning of a
Water Boil Test. It is likely that the pot
was placed in the stove before the fire
was burning well.
Figure 42. The traditional three‐stone
stove producing smoke while cooking.
About half the women responded
that the three‐stone stove produces
less smoke and that its smoke is more
easily dispersed by the wind.
45
poorly, the fire would take longer to start and the smoke would persist for longer periods of
time. The validity of these personal observations were corroborated by the interviewees
responses, based on decades of experience lighting cooking fires.
“If you set up the firewood, you will not have smoke, it just catches fire and it will
be done cooking.”
Once the fire had caught well within the clay stove, the smoke would stop. If the traditional
stoves did not ignite well, they would also produce smoke, as smoke is the byproduct of the
incomplete combustion. Preparing a well‐built fuel wood structure in the stove can potentially
reduce or prevent smoke by improving combustion. Furthermore, those who felt that the
traditional stoves were not as smoky as the improved cook stove noted that the traditional
stove has more openings which provided better ventilation and smoke dispersion.
“The rock stove doesn’t have smoke because the smoke leaves from the open
corners.”
“Yes, the clay stove can have smoke. Because sometimes when the wood isn’t
burning well, the smoke doesn’t have a place to pass”
“With the clay cook stove whenever you start the fire, if the pot is close to the
fire, you will have smoke. If you have a window for the smoke to pass and the pot
isn’t on top of the fire, it won’t smoke.”
If the fire isn’t burning well to begin with or the flames are being stifled by the pot, the clay
stove will produce smoke because there is not enough ventilation. It is important to note that
often smoke is caused by placing the pot in the stove too early, before the fire has a chance to
ignite well. If cooks waited to set the pot in the stove until the fire was good and strong, this
would substantially reduce the smoke emissions. The traditional stove will also produce smoke
if the wood is not burning well, but there are more avenues for it to escape and potentially
easier to disperse because of the wind. However, while more openings in the traditional stove
might allow the wind to clear out the smoke, the open‐layout exposes the fire to the wind, and
the traditional stove is unable to contain the hot ash and charcoals which pose a high risk of
causing a kitchen fire. During her interview, one woman offered a design solution to improve
the clay stove’s ability to disperse smoke while still maintaining its safety features.
“Because for me, I have experience with this, the clay stove only has one opening,
I was thinking that if I made another hole in each side the smoke will leave. So
much smoke comes out of the one main opening. You cannot fan it out.”
46
By making holes on the side walls of the clay stove, it could provide more ventilation and
openings for the smoke to pass through. This could be a potential solution applicable to other
women who believe their improved cook stoves produce more smoke than the traditional
stove. Additionally, her response indicates that the clay stove design can be adaptable and
improved upon to meet individual needs. It is not rigid in design, form, or functionality and can
be made to accommodate user preference. Adaptability is a crucial aspect of stove acceptance
and adoption and the CREATE! stove’s ability to be adaptable encourages cooks to use it
exclusively over less efficient stove options.
The design of the clay stove also makes it both more durable and more secure to cook
with. Women consistently mentioned that the clay stove lasted longer and held the pot more
securely than the traditional stove. When the clay stove is being built, it is form fitted around
the pot which later prevents the pot from tipping over and spilling. When using the traditional
stove, the pot can be unstable because it is placed on misshapen rocks or bricks which are
placed on unleveled surfaces and the stones are susceptible to breaking from the constant
intense heat of the cooking fire. If a rock crumbles while cooking, is accidentally bumped into,
or is shifted while adjusting the firewood, the pot could easily fall and spill onto the floor.
“When you put the pot on the rocks, the rocks can be unstable and the pot will
fall over. But if it is the clay stove, when you put the pot on it fits in well. It is its
size. If you put in the pot, you don’t have to adjust it. It is easier.”
“The rock just needs to be a little tilted and the pot will spill. Or if you’re cooking
for a while with a hot fire, the rock will break. Usually around one month they will
break. The clay cook stove is much better.”
“The clay cook stove, you know it’s almost at 3 months, the one I have, and still
nothing has happened to it. Now if it was the rock stove, when cooking all of the
rocks will break into many pieces. But the clay cook stove isn’t made of dirt,
doesn’t have anything that could break inside, the clay stove each one you see is
still here in village is unbroken, they’re still beautiful.”
The women recognize that the clay stove guarantees stability and durability while cooking. They
do not have to find new rocks or bricks every month that are large or level enough to support
the cooking pot and they can have the confidence of knowing that their meal will not be ruined
by an unstable or crumbling stone (Fig. 43). These are all very positive attributes of the
improved cook stove supplemental to its improved fuel efficiency.
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During their interviews, the women were asked to discuss any problems they
encountered while using the clay stove. They were also asked if there were aspects of the
traditional stove that were better than the clay stove, and if there was any way in which the
clay stoves could be improved. While all of the women firmly advocated for the advantages of
the clay stove, a few identified issues they’ve had with the improved stove that appear to be a
result of the poor ventilation in the clay stove.
“Do you know what is the problem? If you put in the firewood and it is burning
and the flames are high, and a person comes looking for fire and breaks off a
piece of the wood, and puts it back where it was, the firewood doesn’t catch fire
again. That is the only problem.”
“The doorway is too small. If you compare it with the other clay stove, they aren’t
the same.”
In Senegal, it is common for women to visit each other’s kitchen huts and ask for hot charcoal
to start a cooking fire in their own stove. To obtain the charcoal, the women take a piece of
burning wood from the stove and break off the burning end pieces and return the wood to the
stove. The problem that one woman encountered was that whenever someone came to collect
charcoal and they returned the firewood back into the stove, it would not reignite. This meant
that she had to remove the cooking pot, add more tinder, and restart the fire. It is possible that
there was not enough oxygen or ventilation in the enclosed stove for the firewood to reignite
when placed back into the stove, however, it is more likely that there was not a solid base of
hot coals or enough burning firewood to restart ignition. This issue did not appear to be a
commonly shared problem nor did it dissuade the respondent from continuing to use the
improved stove. The second issue discussed was that when building the clay stove, the women
made the fuel wood opening too small. A small opening means that the fire is receiving less
ventilation and the cook must continuously fan the flames to get a good fire. This relates to one
of the potential disadvantages of handmade stoves which is a lack of standardization between
Figure 43. The rocks of this traditional
three‐stone stove are degraded and
broken from constant use. Unlevel
rocks such as these cannot reliably
stabilize the cooking pot.
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stoves. Not all clay stoves are made to the exact same measurements and improper
construction design can hinder the performance of the clay stove. However, this problem has
not dissuaded the cook from continuing to use the clay stove and it can still be modified or
rebuilt. These were the only two criticisms of the clay stove any respondents brought up during
the interviews. The majority of respondents stated they had no problems with their clay cook
stove and only provided praise.
“Since when I built it, I have never had a problem with it. Every day we are happy
with it.”
“The rock stove, anything you can think of went wrong.”
During my conversations, I discovered that there had been several models of clay stoves
introduced to the community of Ndorong Sereer. It was surprising to find that none of the
earlier clay stove models had been rebuilt in the village, given the overall enthusiasm and wide
spread embrace of the CREATE! stove. When asked about their previous experiences with clay
stoves, the women responded that they performed just as well as the CREATE! model, were just
as durable and safe, but apparently more difficult to build and repair.
“To build it was a lot of work. That’s why we haven’t rebuilt them. But everyone
can build one.”
“The one we made now was easier to build because the other stove was very
large. Nearly a meter. Whenever I was cooking I had to stand.”
“It’s difficult. You need a lot more materials for the old one than the new one.
You pound and sift, pound and sift. Now I’m too old to pound, I can no longer
pound.”
The previous clay stoves required a metal mold, used dried cow dung in addition to clay, and
required more intensive labor. The metal mold provided a frame for the stove and women
would pound the materials inside the frame around the pot. My host mother told me offhand
that many of the pot handles in the village are now broken, including her own, because of
accidently pounding them with the large pestle. In addition to being more labor intensive, there
was a different method for disseminating the stoves. Several women and a man from the
village were invited to a training to learn how to build the stoves. They returned from the
training and anyone who wanted a stove had to pay 150cfa (around 20 cents USD) and they
would come build it for them.
“The training that the people went to, the people who went don’t want to help
rebuild them. They don’t like to work. The man who went and organized the
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training passed away. But he said that the materials are here and if you want to
build another one you can come and get the materials. But no one came. The one
we built now, more people have stoves with this one. Everyone in the village has
this stove. The other stove, not everyone had a stove.”
It was mentioned multiple times that not everyone in the village had a clay stove, so there was
less incentive and inertia to organize a village‐wide renewal of the clay stoves. Furthermore, it
was mentioned by several respondents that the people who attended the training appeared to
be unmotivated to help rebuild other people’s stoves, as well as the villagers themselves who
did not gather the materials themselves to rebuild their own stoves. The CREATE! stove was
taught to four women from Ndorong Sereer who helped other women build the stoves at no
cost on the condition that those who wanted a new stove must gather the materials
themselves and learn how to build a stove by helping build their neighbors stove. Through this
cooperative technology dissemination process, more women showed up to build the stoves
because they realized they would receive more help when it came time to build their own
stoves. Because of their participation in building the stoves, all of the women have the capacity
to build and repair their stove and do nott need to acquire an external frame or mold to do so.
While it is certainly not a guarantee of the CREATE! stove’s continued success in Ndorong
Sereer, it was reassuring to discover that all of the women indicated that they would rebuild or
repair their clay stove when it breaks.
“Yes, we will want to have another if it breaks. Because it makes life easier.”
“The clay stove doesn’t have any problems. Once it breaks we want to have
another one.”
“This stove is much easier to fix. Much easier. You know, the women went and
learned how to make these stoves, we are here in the village, if we want another
one, we will ask one another. Whoever wants one, we will come and help fix it.
We will call all of each other to meet and discuss. After we will gather the
materials and fix them.”
The women’s responses reveal that they perceive the clay stove to be superior to the
traditional stove. They reported that the clay stove was more efficient because it uses
significantly less wood and requires less time to cook, that it reduces the work of harvesting
firewood, that it is safer because it prevents cooking accidents like kitchen fires and burns, that
it is convenient because it keeps their kitchens cleaner, that it is more durable and more secure
for their cooking pot. While at times it has smoke like the traditional stove, it is also adaptable
and there are ways to reduce the smoke emissions. Based on all of these advantages and their
50
willingness to build a new stove when it breaks, I conclude that the CREATE! stove is a highly
appropriate and sustainable technology for Ndorong Sereer.
Conclusions
The primary goal of this study was to determine if the CREATE! stove was a more
sustainable alternative for cooking in rural Senegal than the traditional three‐stone stove. To
realize this goal, this study developed and carried out three objectives; to assess and compare
indicators of improved stove performance between the CREATE! stove and the traditional
three‐stone stove by conducting the WBT and the CCT; to gain user perspective about the
advantages and disadvantages of both stoves through exploratory interviews; and through the
analysis of these results, determine if the CREATE! stove is an appropriate and adoptable
technology for the community of Ndorong Sereer.
In terms of stove performance, the CREATE! stove significantly outperformed the
traditional three‐stone stove for the WBT and the CCT. The results from the WBT indicate that
the CREATE! stove was 13% more efficient and required significantly less time to boil by 3.5
minutes than the traditional stove. The differences in wood reductions between the two stoves
were more substantial and significant in the CCT, where the CREATE! stove used 33% less wood
than the traditional stove, though cooking with the CREATE! stove did not significantly reduce
the cooking time. The cook test is a more accurate representation of the stove’s performance in
real day‐to‐day life. However, the CCT was not able to be conducted with the same level of
repetition as the boil test for several reasons. One reason was that the cook tests could only be
conducted once a day unlike the boil tests which could be conducted five times in a day.
Furthermore, since I was purchasing the food for particular families, this began to cause tension
with other relatives in their compound who did not understand why I was not also buying lunch
for their families as well. Had I been able to conduct more tests, the CCT results would have had
stronger validity and perhaps revealed an even greater difference in wood reductions and other
performance indicators between the two stoves. Despite these setbacks, the data that was
collected was sufficient to exhibit statistically different results between the two stoves.
The results from the WBT and the CCT were supported by the amount of wood savings
reported by women during their interviews. The women reported using significantly less wood
and smaller pieces of wood when cooking with the CREATE! stove. These reductions in wood
use had a positive impact on the women’s lives and the state of the forest because it reduced
the number of days per week they have to collect fuel wood. In addition to improved efficiency,
the women brought up a number of advantages of the CREATE! stove that have helped improve
their lives. One of the most important advantages was that cooking with the CREATE! stove was
said to be considerably safer than the traditional stove because it prevented kitchen fires by
protecting the hot coals and ashes from being swept up by the wind. Furthermore, the CREATE!
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stove was said to be more durable and better able to securely stabilize the cooking pot than the
traditional stove.
In addition to these advantages, an important design aspect of improved cook stoves is
to reduce smoke emissions when cooking. When asked to compare the smoke output between
the two stoves, many women responded that the CREATE! stove produced just as much smoke
as the traditional three‐stone stove. However, it was unclear whether the CREATE! stove design
or the user was responsible for creating the smoke. It was widely acknowledged that if the user
did not allow time for the firewood to start burning well before the pot was put on the stove,
the CREATE! stove would produce smoke. Although it is uncertain if the CREATE! stove reduces
smoke emissions, it certainly requires less supervision while cooking thereby reducing the
women’s exposure to smoke by reducing the amount of time they have to spend in the kitchen.
In Bensch and Peters (2015), it was found that even if an improved stove emits smoke, women
can still experience positive health effects if the stove also promotes “exposure‐relevant
behavioral changes”. It was evident through the women’s responses that CREATE! stove does
not require them to be nearby to supervise and tend to the fire and that they take full
advantage of this opportunity by completing other tasks outside the kitchen while they cook.
Therefore, the women are receiving the health benefits of reduced smoke exposure whether or
not the CREATE! stove produces smoke.
The success of a stove adoption and dissemination program is determined by the
number of stoves actually being used and the extent that it replaces traditional stove use (Bailis
2007, Burwen 2011). It is not simply the amount of stoves disseminated or constructed, but if
the stoves are earnestly adopted and if the impacts of their benefits are fully realized (Burwen
2011). The CREATE! stove was built for every kitchen in every compound and has been the
primarily vessel for cooking ever since it was built. All of the women recognize and benefit from
the advantages of the CREATE! stove and on all accounts feel that the CREATE! stove is superior
to the traditional stove. The CREATE! stove has made such a tangible improvement in their daily
lives that all of the women reported that they would repair or rebuild the CREATE! stove when
their current stove was no longer usable. Based on their responses and motivation to continue
using the stove can be concluded that the CREATE! stove is an appropriate and sustainable
technology for Ndorong Sereer.
Many rural villages in Senegal also experience firewood scarcity and are susceptible to
all of the safety issues and disadvantages inherent in using the traditional three‐stone stove.
Since all of these villages prepare similar meals, have similar cooking practices, and use similar
fuels, it is highly likely that the CREATE! stove can be an appropriate and sustainable technology
for them as well. The necessary materials for constructing the stove are free and readily
available in virtually all villages in Senegal, the only missing factor is awareness and the
dissemination of knowledge. However, this dissemination is beginning to occur as nearby
villages to Ndorong Sereer and the CREATE! training center become aware of the improved clay
52
stove. Already, two neighboring villages have asked the women to hold trainings and help them
construct CREATE! stoves in their compounds. Peace Corps Volunteers from different regions of
the country are bringing women from their villages to the CREATE! training center to learn how
to build the improved clay stove.
However, it is uncertain whether these villages will experience the same dissemination
success as Ndorong Sereer. The women who went to the training were highly respected and
highly motivated members of their community who, at no cost, took the initiative to help train
other women who were interested in constructing a stove and had collected the materials on
their own. It is possible that others who acquire the knowledge and skill on how to build a
CREATE! stove might lack initiative, demand money for their services, or do a poor job of
constructing the stoves. Furthermore, Ndorong Sereer was a unique community in that it is
open to trying new ideas and technologies perhaps in part due to hosting multiple Peace Corps
Volunteers in the past. Regardless of community dynamics, it is undeniable that the CREATE!
stove is a culturally appropriate technology and sustainable cooking alternative that can
produce real, significant, and positive impacts for the environment and for the lives of women
in rural Senegal.
Future Research
While conducting this study, I encountered many future research opportunities
pertaining to the CREATE! stove design, performance, and dissemination. One such
opportunity, which could help provide clarity to this study, would be to incorporate methods
for quantifying the differences in smoke emissions between the two stoves. This study solely
relied on qualitative methods in analyzing user perspective through interviews to assess smoke
emissions between the two stoves and was unable to determine if the CREATE! stove
quantitatively produces less smoke as is claimed by CREATE! NGO. Additionally, fuel wood
collection time was also derived from interviews. Future research could focus on the
quantitative impacts of fuel wood reduction on the forest by measuring the frequency of
collection as well as the weight and type of firewood bundles being collected and brought back
for cooking. Another opportunity would be to conduct more Controlled Cooking Tests with the
CREATE! stove to have more robust data on wood reduction and cooking time. As mentioned
before, this study was only able to conduce 11 CCTs and could have greatly benefitted from
more data. In terms of dissemination, it would be beneficial to explore how other villages
disseminate the knowledge and construction of the CREATE! stove and if there are
dissemination methods or conditions that enhance the chances of higher rates of adoption.
Furthermore, there are several different types of improved stoves in Senegal, the most popular
being the Jambaar stove. An interesting future study would be to compare the performance
and user perspectives between the CREATE! stove and the Jambaar stove. While the Jambaar
53
stove costs money, unlike the CREATE! stove it can also be easily transported, adapt to any size
pot, requires no previous knowledge or skill set, is widely available, and is arguably more
durable than clay since it is made from metal.
54
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Personal Interview
Ndiaye, Bassirou. Community Member and Peace Corps Counterpart of Ndorong Sereer. (2014).