the manica charcoal stove project

Abstract

A study was conducted by staff and students fromthe Department of Industrial Design in the Facultyof Art, Design and Architecture (FADA) at theUniversity of Johannesburg on alternative charcoalstove design under the title Manica Charcoal StoveProject for developing communities. The projectwas started in support of the principle designsdeveloped for the Maputo Ceramic Charcoal Stove,now known as the Poupa Carvão (POCA) charcoalstove, developed by Crispin Pemberton-Piggott ofthe Program for Biomass Energy Conservation(ProBEC) which is supported by GIZ. A researchgroup consisting of two academic staff membersand four 3rd year Industrial Design students visitedthe town of Manica in Mozambique in 2008 to com-plete user field testing and use these results toinform alternative charcoal stove designs. The proj-ect falls under the broad area of design for socialdevelopment and expands on aspects of communi-ty centred design developed within the Departmentof Industrial Design at the University ofJohannesburg. This paper briefly describes theresearch method and the design process used todevelop the stove concepts. It discusses aspectsrelated to the design of new charcoal burning stovesand touches on the manufacturing systems availablefor stove production in the region. It evaluates theprinciples of user centred design in developing com-munity projects and gives direction to further stud-ies of this kind.

Keywords: community centred design, user centreddesign, design for development, charcoal stovedesign

1. IntroductionIn August 2008, a field study was completed inManica, Mozambique, on alternative charcoal stovedesign under the title: Manica Charcoal StoveProject. A group consisting of two academic staffmembers and four 3rd Year students from theDepartment of Industrial Design at the University ofJohannesburg visited the town of Manica inMozambique to complete user acceptance testing inthe field and use these results to inform alternativecharcoal stove designs. The field trip was the culmi-nation of several months of research, design anddevelopment work that had started in the depart-ment in May 2008.

The project was initiated in support of thedesign principles of an improved clay charcoalstove developed by Crispin Pemberton-Piggott forthe Programme for Biomass Energy Conservation(ProBEC).1 The first version of the improved claycharcoal stove was called the Maputo CeramicCharcoal Stove2 (see Figures 1 and 2) and laterbecame known as the Poupa Carvão (POCA) char-coal stove.

In May 2008, the Department of IndustrialDesign was approached by ProBEC to re-engineerthe Maputo Ceramic Charcoal Stove in metal. Atthat stage, the ceramic materials used in the MaputoCeramic Charcoal Stove proved to be problematicin that the stoves would crack after little use and thestoves were brittle and could break if accidentallyknocked over. The entire 3rd Year group of indus-trial design students were involved in the initialstages of research, design and development of ametal translation of the original stove based on theworking principles developed by ProBEC for theMaputo Ceramic Charcoal Stove.

The working principles given to the studentsbased on the Maputo Ceramic Stove were:• The stove requires a specific ratio of air coming

in through the base.• The air entering into the burn area should be

preheated.• The fire grate should have the optimum amount

of air coming in below the coals as too little airwill choke the combustion, while too much airwill cool the flue gases.

2 Journal of Energy in Southern Africa • Vol 24 No 2 • May 2013

The Manica Charcoal Stove Project

Chris BradnumDepartment of Industrial Design, University of Johannesburg, South Africa

Figure 1: Maputo Ceramic Charcoal Stove, 2008

(Photograph: A. Campbell)

Figure 2: Maputo Ceramic Charcoal Stove, 2008

(showing charcoal burn area and air gap

surrounding it)


• There needs to be a gap around the edges of theburn area to allow a specified amount of air toflow over the top of the coals.

• The stove should be insulated to improve thepreheating of air to the burn areas and to ensurethat the stove limits the loss of radiating andconducting heat from the burning charcoal thatis not directed towards the pot.

• The ratio of air released between the pot and thestove top (pot holder area) should also be con-trolled and allow for a specific amount of air toflow out.

• The shape of the stove body should encouragean acceleration of hot gases as they are pushedtowards the pot base.

• The configuration and layout of the MaputoCeramic Charcoal Stove should be maintainedas far as possible.

The primary objectives for adapting the workingprinciples must result in:• A reduced amount of charcoal used to effective-

ly cook meals.• The complete combustion of the charcoal and

gasses to increase the energy output and reducetoxic emissions.

• The maximum use of energy potential from theamount of charcoal used.

• The reduction of the amount of charcoal used toassist in slowing the rate of deforestation inSADC regions.

• The stove should be able to burn lower gradecharcoal (from fast growing trees) to reduce theloss of rare indigenous hardwood trees.

The project set up at the university required thatthe entire group of 3rd year students develop twodistinct solutions for their stove designs: a versionsuitable for mass manufacture and a craft manufac-ture version. The mass manufacture version wasintended for manufacture at production facilities inindustrialised centres such as Johannesburg orMaputo and the craft version was intended for man-ufacture at village level from a set of instructionmanuals and templates developed for this purposeand using materials and manufacturing processeson hand.

At the end of the concept phase, students man-ufactured prototypes of their solutions, which werethen tested by ProBEC using a standard efficiencytest. ProBEC found that many of the stoves showedsignificant efficiency improvements from traditionalmetal charcoal stoves found in Mozambique andcompared well with the results they were gettingfrom the Maputo Ceramic Charcoal Stove. A com-ponent missing from this design project however,was the actual stove user. This is a regular failing ofprojects intended for developing communities: thedesigners working in isolation from the people whowill eventually use the product.

Participatory design integrates two radicalpropositions about design. The first is the moralproposition that the people whose activity andexperience will ultimately be affected most by adesign outcome ought to have as substantial sayin what that outcome is … the second is thepragmatic proposition that the people who willneed to adopt, and perhaps to adapt to an arte-fact or other outcome of design, should beincluded in the design process, so that they canmore offer expert perspectives and preferencesregarding the activity that the design will sup-port, and most likely transform. The pragmatic

Journal of Energy in Southern Africa • Vol 24 No 2 • May 2013 3

proposition is that directly including the users’input will increase the chances of a successfuldesign outcome. (Carroll & Rosson, 2007: 243)

In preparation for the launch of the MaputoCharcoal Stove, ProBEC asked Dr Peter Coughlinto conduct a baseline study on charcoal stove use inMaputo in 2007. According to Coughlin, the aimfor ProbBEC to introduce the ceramic stove pro-gramme was ‘…not only to introduce a much moreefficient charcoal stove but also to promote moreenergy efficient cooking techniques to save charcoaland, hence, trees and reduce people’s exposure tosmoke, a major cause of respiratory illnesses’(Coughlin, 2007:1). Coughlin’s baseline study wasused to determine amongst other considerations the‘practices used by people when cooking on tradi-tional [metal] stoves’. Furthermore, the study wouldascertain the environment in which stoves wereused, and the frequency and duration of use.Although these components are crucial to the gen-eral understanding of users engagement with theircooking technology, this study does not includeusers as a component of the decision makingprocess in the development of an improved stove.In this author’s opinion, the Maputo Charcoal Stovecan therefore be understood as the introduction ofappropriate technology from an outside sourcerather than an inclusive co-creation or user centreddesign process. The Department of IndustrialDesign has been involved in many communitydesign projects in which the community inform theprinciples of the design. From experience, thisapproach leads to a greater acceptance of the prod-uct and a solution that is sensitive to the actualneeds not simply the technology being produced.

Fortuitously the class work phase of the projectended at the same time as calls for entries to theSanlam Creativity for Progress Competition werelaunched.3 The university’s Corporate SocialInvestment division sent Schalk van Heerden4 tothe Department of Industrial Design to evaluate thepotential of the stove project as an entry for thecompetition. Van Heerden believed that the projecthad merit and in discussions he provided details ofthe research he had been involved in within thetown of Manica in Mozambique. From his experi-ence in this town he indicated that residents usecharcoal as the main source of energy for house-hold cooking. They also use a stove which is man-ufactured by metalworkers in Manica and that thereis a growing problem of deforestation from charcoalproduction and usage. He suggested that thedepartment continue the research in Manicatowards the development of an improved charcoalstove.

The opportunity to interact with stove users,stove manufacturers and even charcoal manufac-turers was an excellent prospect to further develop

the product and also provide the students and aca-demic staff with a real life project in which theycould further develop their expertise of product userinteraction and community centred design projects.

A group of four of the industrial design third-year students volunteered for the further researchand development of the charcoal stove, now thenewly named Manica Charcoal Stove Project. Theresearch group that went to Manica in August 2008comprised students: Victor Bezuidenhout, TheoOlivier, John Harverson and Ross Nelson; two aca-demic staff members: Chris Bradnum and AngusCampbell; as well as Schalk van Heerden as theexpert on the region and member of the adminis-tration of the soccer club: Groupo Desportivo deManica from where the project was run. At the endof the project, the students and academic staff wererequired to complete reports on the project for thedepartment and for the Faculty of Art, Design andArchitecture’s Research Newsletter. Much of thispaper draws on these reports.

2. User-centred design processThe concept of user-centred design has arguablygiven rise to one of the most fundamentalchanges in the field of design over the past fewdecades. Design has since shifted focus fromgiving form to objects and information toenabling user experiences, and from physicaland cognitive human factors to the emotional,social, and cultural contexts in which productsand communications take place. (Boztepe, 2007: 57)

The design process used for this project was loose-ly based on the process of user-centred design byvan Buurman (1997) as discussed in Kahmann andHenze (1999: 114 in Green and Jordan, 1999) (seeTable 1) but adapted by the research group for thespecific needs of the project. The research groupinvestigated the town of Manica to contextualise theenvironment, cooking processes, stove technologyin use and manufacturing processes available.Stove users were asked to demonstrate typicalmeals being cooked by using the locally manufac-tured Fugão, observations and interviews of theseprocesses were recorded. The research group con-ducted interviews with local craftsmen, shop ownersand stove users to understand technical factorsinfluencing the manufacture and sales of stoves.Through the combined set of interviews and directdemonstration the research group were able tounderstand the principles of stove use and formu-late a stove use profile.

Design research is not only concerned with thetechniques for planning and giving form to aproduct but also with use. Since products aremade for people, the user response to a product


is an essential part of the research field. Becausethe subject of design research, then, is not onlyof products but also the human response tothem. (Margolin, 2000)

Once the contextual research and data gatheringphase of the design process was completed theresearch group had developed a comprehensiveunderstanding of many of the factors that influencestove users, stove use, stove manufacturers and theissues of charcoal production. Through this processthe research group became sensitised to some ofthe complex issues of the region and the communi-ty. These factors were then applied to the develop-ment of a number of design solutions which werediscussed with local users and stove manufacturers.User testing on the stoves and basic efficiency testswere conducted. Some of the stoves went througha phase of further refinement before the field tripwas completed.

3. Contextualising the field research and datagatheringThe first phase of community design projects is tocontextualise the people and place. In this research

and development project, the research group werefortunate enough to have members of the soccerclub, Groupo Desportivo de Manica, where theresearch group based its research, to assist with andrefine the information gathered. To this end, theresearch group relied on Schalk van Heerden for hisinsight gained from living in the region and theresearch completed for his mini thesis; interviews,conversations and confirmation of these withNelson Veremo, an English teacher and administra-tor at the soccer club who has lived and worked inManica his whole life; and Shortcover Chikwan-dingwa, the General Manager at the Grupo Des-portivo de Manica, who also happens to be highlyregarded musician in Southern Africa.

3.1 Manica, Mozambique

Manica town is situated in the province of Manicain Mozambique around 20 km from the border withZimbabwe on the Mutare – Beira highway. This linkis also known as the Beira Corridor which connectsMalawi, Zimbabwe and Zambia to the port of Beira.Before the Portuguese were expelled fromMozambique in 1974, Manica was known as Mace-kece. ‘On 6 September 1974, more than 400 years


Table 1: User-centred / community-centred design process informed by ‘The process of

user-centred design’

Den Buurman, 1997 by Kahmann and Henze, 1999: 114 in Green and Jordan, 1999

of Portuguese rule in Mozambique came to an end‘officially’ (Swift 1974:184)5 (van Heerden, 2005:20). The remnants of the Portuguese era can beseen in the ill maintained, but still structurally soundbuildings in the town. This gives the town a Luso-African6 appearance in this African landscape.Manica has a population of around 40 000, withShona and Portuguese being the main spoken lan-guages. Portuguese is the language of all educationin schools and is used for all the signage in thetown. Manica is surrounded by hills and mountainsand is itself reasonably hilly, but flattens out as youmove eastwards towards the town of Chimoio.

3.2 Cooking economy

Within Manica town and the surrounding area, themajority of the population use fire as the mainsource of energy to cook food. The systems rangefrom the traditional three stone cooker which useswood (see Figure 3) through to the metal Fugão(‘stove’ in Portuguese) which uses charcoal (seeFigure 4). The Fugão itself appears to be a productof earlier UN intervention as a similar stove can befound in many areas of development withinSouthern Africa including Kenya, Madagascar andTanzania. The Fugão is manufactured in Manicafrom +/-4mm thick mild steel sheet metal, which isobtained from recycling and flattening sheet metalrailway sleepers. These metal sleepers are beingreplaced with concrete sleepers along the railwayaround Manica and have become a useful resourcefor the manufacture of many products including theManica Fugão. There are other ingenious charcoalstoves used in the area such as the stoves manufac-tured from old car rims (see Figure 5), but the stovemade from railway sleepers is the most popular.

Figure 3: Traditional three stone cooker, 2008


Figure 4: Manica Single Fugão, 2008

(This and all subsequent photographs: V.

Bezuidenhout)

Figure 5: Car rim stove, 2008

The standard Manica Fugão can be purchasedfor 100Mtn (2.83US$)7 for the single stove and200Mtn (5.67US$) for the double stove version. Asecond-hand railway sleeper from which thesestoves are manufactured can be purchased for100Mtn (2.83US$) and from this a craftsman canmanufacture 4 double stoves or 7 single stoves. Themanufacturing tools and processes available tocrafters making these Fugão includes: electricgrinders, hacksaws, arc welding and chisel andhammer beating to complete the work. A singleFugão takes a skilled craftsman about 2 hours tocomplete.

In Manica, a school teacher earns 3500Mtn(99.15US$) per month and the minimum wage inMozambique is 1800Mtn (50.99US$) per month,making the purchase of a charcoal stove a big deci-sion in the average household. Charcoal bags arerated by bag size and bucket quantities. A stoveuser can purchase a single bucket of charcoal for30Mtn (0.85US$) or a small bag (around 3 X 20litre buckets of charcoal) for 70Mtn (1.98US$) orthe large bag (around 5 X 20 litre buckets of char-coal), which sells for 100Mtn (2.83US$) dependingon the time of the year (prices given are winterprices). Winter prices are higher than in summerbecause the rain in summer makes the charcoal


making process easier and therefore most costeffective. The average household, based on twoadults and two children, uses up to one large bag ofcharcoal per month for their cooking needs.

According to van Heerden, (2005: 23):

The main diet of people in Manica consists ofsadza (porridge made from grounded maize)and cove (relish), with bacajão (dried fish)added when sufficient funds are available. Thisis complemented by the eating of pão (bread)and on rare occasions chicken, beef or goat’smeat. Energy needs are therefore satisfied bymainly either firewood or carvão (charcoal) tocook the sadza and relish (cove or bacajão).

3.3 Deforestation

The prime area for charcoal manufacture isbetween 15 km and 20 km west of Manica and canbe accessed along rutted dirt roads. This was thearea in which the Zimbabwe Liberation Army keptcamp during the Rhodesian war. After Zimbabwe’sindependence in 1980, the area became the baseintermittently for Renamo and Frelimo during theMozambique civil war, which lasted from 1976 to1992. After the civil war, farming activity startedreturning to the area and the woodlands began tobe utilised for charcoal manufacture to clear theway for the farming (Chikwandingwa, 2008;Veremo, 2008, van Heerden, 2005). ‘Fuel to cookis obtained predominantly by one of two ways andsometimes by both. These consists of either goingdirectly into the forested areas surrounding the townto cut wood (lenha) or to buy either wood or char-coal in the market (Mercado)’ (van Heerden, 2005:23). However, according to van Heerden, charcoalhas become the predominant source of fuel forcooking in Manica as the trees closest to town haveall but disappeared or are located on farm lands.

In Manica, a tree cutting license is required for allindividuals involved in tree felling activities, otherthan tree cutting on their own land. This license canbe purchased from the local municipality (ConselhoMunicipal da Cidade de Manica) for 570Mtn(16.15US$). The license is valid for a year andallows cutting only in an allocated area. Accordingto van Heerden: ‘Penalties for illegal tree utilisationare also given by the Agriculture Department andinclude financial fines or physical labour like dig-ging or weeding. In extreme cases, people are jailedand in Manica, prisoners are rented out for physicallabour and the income from their work goes intothe state purse.’ (van Heerden, 2005: 29).

There is strong evidence that the tree resourcessurrounding Manica are not being managed well.Through discussions with stove users, communitymembers and soccer club staff, the indications arethat uncontrolled tree felling has changed the land-scape around Manica. The mountains to the North

of Manica are almost barren, where they used to bedensely populated by hardwood trees. There aresigns that trees from the Vumba Mountains to theSouth of Manica are also being used for charcoalproduction. The trees on the Vumba Mountains areprotected by law, but illegal cutting is still takingplace.

From van Heerden’s research he determines thatManica has a good supply of electricity but becauseof the high costs to connect households to the gridand the relative scarcity of electric stoves, utilizationof this resource is well below capacity. ‘As the townof Manica grows and as wealth increases, so wouldthe use of electricity which is viewed as the pre-ferred source of energy for cooking and lighting’(van Heerden, 2005: 34).

4. Product developmentThe product development phase within the Manicacommunity included several research components:observational studies, informal interviews, designthrough experimentation and user feedback andinvolvement as a key component of the decisionmaking processes and further development. Eachof the designs was also tested using a basic waterboil test to determine a simple efficiency calcula-tion. The product development also carefully con-sidered the capabilities of local manufacturers andmany of the prototypes were outsourced to thesemanufacturers. The inclusion of local manufacturersduring this stage allowed the design team to betterunderstand the level of skill, capabilities and limita-tions of these manufacturers.

4.1 Stove use profile

The research group observed users cooking mealson the Manica Fugão and conducted a series ofinterviews to ascertain the process of using thestove. What follows is a collection of observationsand interpretations on Fugão use.

The Fugão are used not only for cooking butalso for heating water for tea and coffee and forspace heating during winter months. The Fugão areoften used more than three times a day for cookingand heating needs. The Fugão is lit in one of twoways: under-lighting using a combination of leaves,paper or tinder; or top-lighting by melting a plasticbag under a match flame and dribbling the burningplastic onto the charcoal. The Fugão are lit outdoorsand once the charcoal is fully alight and the smokedissipates, they are then often carried indoors foruse. The burn temperature of the coals is controlledby facing the opening below the coals into or out ofa draft. This control mechanism functions well evenindoors as windows and doors are generally leftopen during the cooking process to reduce theindoor smoke. Some stove users also cook out-doors in areas surrounding the house whichimproves this control function further.


More charcoal is added to the burning embers toincrease the heat of the fire during the cookingprocess. The food that takes the longest to cook andretains its heat well, such as beans, is cooked firstand left to stand whilst the other food is cooking.During cooking, the radiating heat from the Fugãois used to keep already cooked food warm, by plac-ing the pots around the base of the stove. When thefire is no longer needed for cooking, the charcoalsare placed into a metal dish using wire tongs, andtaken outside and quenched with water or theFugão itself is moved outdoors and the coals arequenched in the stove. By quenching the coals inthe Fugão, the lifespan of the product can be dras-tically reduced as the metal will start to rust and thebody could split apart around the welded joints.The charcoals that are quenched can be re-used, inconjunction with new charcoal, for future cooking.New charcoal is used for the lighting of the fire, andthe used charcoal can be added to the hot fire evenwhen it is still wet. On average, 800 grams of char-coal is used for 1½ hours of cooking. This massincludes the charcoal added during the cookingprocess.

Ash from the fire is valuable to stove users, as ithas many uses. The users believe ash has medicinalproperties: ash is either ingested dry or mixed withwater and then drunk to treat constipation, or usedas a cough remedy. Ash is used as an abrasivemedium to clean pots. The charcoal ash is also scat-tered in and around toilets to deter flies.

The handles of the Fugão are made from a mildsteel rod which is welded to the stove body. Duringthe cooking process these handles become veryhot. Temperature measurements show that the han-dles often exceed 50°C, which makes them danger-ous to touch and can burn the users if they do notuse protective materials to cover the handle duringuse. Fugão users move the stove several times dur-ing cooking and the handles are a key interfacepoint.

4.2 Manufacturing considerations

The approach followed by the research group forthis project, as in many of the community centredprojects the Department of Industrial Design hasbeen involved in, is to source and include localmanufacturers for the implementation of designsolutions. To this end, the research group needed tounderstand the capabilities of local manufacturersas well as materials and processes used. What fol-lows is a collation of data on the current Fugãomanufacturing process as well as additional factorsthat could influence future stove design for manu-facture.

Although the local manufacturers are skilled, thedesigned product should allow for some flexibilityon tolerances as these will not be consistent for allstoves. Manufacturers are intimidated by engineer-

ing drawings and alternate instruction mechanisms,such as sample templates, should be found to assistthem in the stove manufacture. The materials avail-able for the current Fugão are the railway sleeper,but this is not an infinite resource. Material substi-tutes should be found to replace this resource intime. The product needs to be manufactured insuch a way that on-going repairs can be executedeasily. Components or entire sections should beeasy to replace when they break or wear out.

The new stove needs to last between 3 to 5years in order to be competitive, as this is the cur-rent lifespan of the Manica Fugão. When decidingon dimensions, two factors need to be taken intoconsideration; the size and dimensions of the exist-ing stove as well as average pot sizes used for cook-ing. The most commonly used pot in Manica has abase diameter of 230 mm with a depth of 115 mm.These pots are manufactured by skilled localcrafters out of sheet aluminium imported fromZimbabwe.

4.3 Design solutions

The research group began design and developmentwork on the stoves based on the scientific principlesof the Maputo Ceramic Charcoal Stove andinformed by the experience of the stove users inManica. The intention of this phase of the projectwas to develop solutions from concept sketches intophysical test models, test the scientific validity of thenew design through basic efficiency tests and alsotest the user reaction to the designs proposed. Thisphase resulted in several minor improvements tothe current Fugão including: the addition of aremovable ash tray and the addition of a coverplate. In addition to this, several new stoves weredeveloped: the Prism Design, Double WalledFugão, Fugão Based on Scientific Principle, Fugão3 and Fugão 3 Refined, the Pot Skirt, Broken FugãoConcept 1 and Broken Fugão Concept 2. What fol-lows is a brief collection of the more interestingdesigns and some of the results obtained.

4.3.1 Removable ash tray conceptThe intention of this concept was to control andlimit the airflow below the burning charcoal as wellas to include a built in ashtray to clean out andtransport the ash. This concept was not receivedwell by the stove users as the perception exists thatthe large opening improves the function of thestove.

4.3.2 Cover plate conceptA problem identified with the Manica Fugão is theloss of energy through the large gap between thepot and the stove top. The cover plate concept wasdeveloped to harness and direct all the heat to thepot base. The test results were however disappoint-ing as the cover plate did not perform as anticipat-


ed. Not only did the cover plate not improve theperformance of the Fugão, but it created a set ofnew issues. The addition of charcoal during cookingis difficult because the cover plate becomes too hotto remove, the stove generated a lot more smokethan the standard Fugão during operation and thestability of the cover plate was also questionable.The research group decided not to pursue the coverplate concept any further.

4.3.3 Fugão 3The aim of the Fugão 3 concept was to reduce theheat loss through the top opening of the stove, bycutting off the corners and changing them intofaceted faces. This would allow the pot itself to actas an effective seal against heat loss between thestove top and the pot base. This shape also reducedthe amount of charcoal that can fit into the stove.The walls of the base were raised to help insulatethe stove burn area against heat loss and to preheatthe air coming in below the charcoal grate. The pro-totype was manufactured by the students in gal-vanised iron rather than in the sleeper material. Theusers were concerned about the products longevitybecause of the use of the galvanised iron. However,

the users did respond positively to the larger foot-print and the additional stability this might provideduring cooking.

Figure 8: Fugão 3 test prototype, 2008

Figure 9: Fugão 3 detail of cut off corner, 2008

4.3.4 Fugão 3 refinedThis stove design was a development on the Fugão3 concept. Key developments included woodenhandles to improve safe handling of the stove, areduction in the amount of material used for manu-facture from the Fugão 3 concept, a removable ashtray, a larger footprint to improve the stoves stabili-ty, and the double wall base and the faceted corners


Figure 6: Addition of an ash tray to the Fugão,

2008

Figure 7: Cover plate concept, 2008

Figure 10: Engineering sketches of the

Fugão 3 Refined concept, 2008

(Drawing by T. Olivier)

to improve the efficiency. The manufacturers wereconcerned that this stove would add complexity tothe manufacturing process and raise the overall costof the product. Users indicated their appreciationfor the removable ash tray and the inclusion of alarger base and the stability this may offer in use.

Figure 11: Fugão 3 refined, 2008

4.3.5 Double walled FugãoThis stove was developed as a close approximationof the principles of the Maputo Ceramic CharcoalStove. Included in this design was a system to pre-heat the air entering under the coal grate and flow-ing over the top of the fire; an ash tray below thestove; a limited amount of air coming from outsidethe stove; and a limited amount of air enteringbelow the charcoal. The design was manufacturedin Manica by Fugão makers according to engineer-ing sketches and dimensioned 2D drawings sup-plied. However, these drawings appeared to intimi-date the manufacturers and they indicated that theywould prefer templates and step by step photo-graphs to explain the manufacture process required.Although this stove did achieve better results thatthe Manica Fugão, it did not show substantialimprovement and would cost a lot more than thecurrent Fugão because of the additional materialsrequired in its manufacture.

Figure 12: Double walled Fugão, 2008

Figure 13: CAD model of Double Walled Fugão,

2008

(CAD modelling by C. Bradnum)

Figure 14: Double walled Fugão, 2008

4.3.6.Broken Fugão concept 1The Broken Fugão Concept offered a replacementbase for broken stoves, of which there were manyfound in Manica, and improved the efficiency ofthose stoves. The replacement base creates a dou-ble wall, which insulates the fire grate and heats upthe air coming into through the gate below the char-coal. Through this double walled insulation, there isless heat loss from around the fire grate. Thereplacement base also creates an insulating effectaround the pot and directs additional escaping heatup the sides of the pot. However, users were con-cerned that the concept did not include handles tomove the stove in use and this would make itimpossible to control the temperature of the stoveby directing the stove into or out of the wind.


Figure 15: The Broken Fugão concept, 2008

4.3.7. Broken Fugão concept 2This concept develops a replacement base madefrom galvanised steel. It can house any brokenManica Fugão grate top area and handles, wherethe handles of that Fugão act as the supports tohold the stove in place in the new base. The newbase also serves as a pot skirt, and provides thedouble wall to assist in the preheating of air comingin below the charcoal grate. The handles were notpermanently attached to the outer shell makingmoving the stove difficult and a little dangerous.Improvement made to the fundamental principle ofassembly could make this a viable option as thisstove displayed good efficiency results.

Figure 16: The Broken Fugão concept refined,

2008

4.4 Efficiency test process and results

The Partnership for Clean Indoor Air (PCIA) web-site gives details on the three test procedures forevaluating stoves: the Water Boiling Test (WBT), theControlled Cooking Test (CCT) and the KitchenPerformance Test (KPT) (PCIA, 2009). PCIA sum-marise the CCT as a test of stove performance usinga simulation of local cooking methods, food types,fuels and cooking pots in a laboratory environment.The KPT is a field test assessing household fuelusage when using the stove to complete daily cook-

ing tasks. The testing completed in Manica did notinclude formal CCT or KPT tests because of thetime constraints of the field test period, rather test-ing focussed on a version of the Water Boiling Testto test efficiency and some informal cooking testswith stove users making meals on some of thestoves. ‘The Water Boiling Test (WBT) is a simpli-fied simulation of the cooking process. It is intend-ed to help stove designers measure how efficientlya stove uses fuel to heat water in a cooking pot andthe quantity of harmful emissions produced whilecooking.’ (WBT 2009:1).

The research team conducted a version of thewater boiling test on each of the stove designs, aswell as on the original Fugão, centred on Prof PhillipLloyd’s test procedure for paraffin stoves. The selec-tion of this test method was based on the author’sprevious experience on paraffin stove testing andthis was deemed to be a viable basic test method forthe limited time available in Manica (EfficiencyTesting, 2004). This simple process includes weigh-ing the stove, the charcoal, the pot and the water atthe beginning of the test. Additional charcoal wasalso set aside and weighed to allow the testers toadd charcoal during the test process, if and whennecessary. The stove was then lit. Once the waterreached boiling point, measured by temperatureand rapid bubbles in the pot, incremental measure-ments were taken at intervals of 5 minutes over a 30minute period. At the end of the test, the weight ofthe used charcoal loss was calculated as well as theamount of water that was lost due to evaporation.By using Lloyd’s efficiency calculation, an efficien-cy percentage was calculated for each stove. Figure18 indicates the various stoves’ levels of efficiency,relative to one another (see Table 2).

An efficiency field test kit was transported fromthe university to test the stoves on site. This kit com-prises a 30 kg electronic scale, an electronic ther-mometer, a cylindrical measure, stop watches,verniers and calculators. For the efficiency test pro-cedure, the following calculation was used:


Figure 17: The Broken Fugão concept refined

engineering sketch, 2008

(Drawing by T. Olivier)

Efficiency = (MW*HW)/(Mf*Hf)

In this calculation:MW = weight loss of water over timeHW = latent heat of water 2 260.74 KJ/kgMf = weight loss of fuel over timeHf = calorific value of charcoal 31 448.9 KJ/kg(Efficiency Testing, 2004).

Figure 18: Tests being carried out on Fugão 3,

2008

Figure 19: Tests being carried out on the

Manica Fugão, 2008

The initial testing on the field trip did not yieldany results as the stoves were unable to arrive at aboiling temperature for the water. A revised versionof tests reduced the amount of water to 1 litre andused a LPG gas stove to bring the water to boil toallow for the testing to be conducted, the tests werethen run for 30 minute sessions.

Table 2: Stove efficiency test results, 2008

The results of the testing showed the most posi-tive efficiency for the stoves which included potskirts. Including a pot skirt or at least directing theheat around the sides of the pot improves efficien-cy and thereby reduces the amount of charcoalrequired.

4.5 User feedback on stove designs

‘Social entrepreneurs’, says Dees, ‘make surethey have correctly assessed the needs and val-ues of the people they intend to serve and thecommunities in which they operate. In somecases, this requires close connections with thosecommunities.’ Similarly, it is vital that social-impact designers put the needs of the communi-ty they are serving above all else. This may seemobvious — designers generally work with theuser in mind and push their designs to fulfil theuser’s desires. But in traditional design, suchinterests are matched with the needs of the busi-ness, producers, and even designers themselves.Social design must step back from that balancedapproach and put users at the fore of all designactivities. Only then is it possible to honestlymake an impact, not merely create a well-designed object. (Ford, 2010)

Figure 20: A community member looking at

some of the data gathered, 2008

The research was conducted from the DesportivoSports Centre, in the heart of Manica town. Fromthis location the research group were able to con-stantly involve the community throughout the


Original Fugão 0.125

Fugão 3 0.127

Double Walled Fugão 0.134

Broken Fugão concept 2 0.151

Round Pot Skirt 0.233

Broken Fugão concept 1 0.251

design process. Drawings were put up on the wallsoutside the club, research findings were posted andassumptions were dispelled through inviting thepublic off the street to discuss all aspects of the proj-ect. Stove testing was conducted at the entrance tothe club, virtually on the street, and this drewcrowds of interested onlookers who also offeredtheir opinion on the design progress. The initialthoughts and gathered data were posted on the wallof the Desportivo main building, so that anybodywho was interested could look through the workand offer comment. In this way, the research groupreceived constant feedback from community mem-bers.

Figure 21: User testing of the Broken Fugão

concept 2, 2008

The research group completed user testing on allthe stoves designed. User groups were set up toinvestigate the potential for the new stoves. A fewunstructured cooking exercises with participantscooking a local meal on each of the stoves wereconducted. The results of these tests allowed for fur-ther development and refinement of the stovesdesigned. Although the best performing stoves,which included the pot skirt type concept, wouldshow a decrease in the use of fuel over an extend-ed period of time, users were concerned about thecost implications when purchasing the stove, theissues of the varying pot sizes and pot skirt fit, andthe possibility of burning their hands on the pothandle in use. Given more time, the research teamwould have liked to have commissioned the manu-facture of a series of these stoves in the area and runextended home use tests. However, this was notdone and can be seen as a limitation of the project.

5. Conclusion and recommendationsThe field study component of the Manica CharcoalStove Project took place over 14 days, a very shortperiod of time. Within that time, an enormousamount of data was collected and should be usefulfor future projects in the area. However, a longer

period of investigation will uncover more of thesubtleties of cooking, lifestyle and needs of the com-munity. Additionally, as the researchers gain thetrust of the user group, the feedback and interactionon design solutions will become more direct andhonest.

This project needs more work. With more fund-ing and more user testing, the ambition is to devel-op a reasonably efficient stove for the short termwith improvements and developments in efficiencyhappening over time. This could then be translatedto areas outside of Manica and possibly to otherSADC countries. However, in the same way that theusers of Manica needed to be consulted throughoutthe design process, other users in other countrieswill require similar opportunities to be involved inthe development of a product that will impact ontheir lives.

The principle design technology developed forthe ProBEC Maputo Ceramic Charcoal Stove,although good, has not considered the users wellenough and would certainly be difficult to introduceto a town like Manica. Designers need to interactwith users of their products in order to grasp boththe complexities and subtleties of use. The trip toManica resulted in many design solutions, with thepot skirt type designs showing the best potential forfurther development for manufacture and imple-mentation. All of the stoves designed included usersin the process of development and also includedlocal manufacturers. With further development, it ispossible that a good design solution could be testedin a final phase of user interaction and that theresulting product could be made into templates forlocal manufacturers to produce.

As the department becomes more experiencedat community and design for development projects,a few reoccurring guiding principles start to emerge.Each community centred project has its own chal-lenges and it is difficult to formulate a single set ofrules before starting these types of projects. A keycomponent to the success of such products is tohave good contextual research, excellent and reli-able advisors who have sensitivity for the peopleand the region, and a research and design groupwho are willing to listen to the users and experimentwith solutions around the issues identified.

Beyond this, the following recommendationsmay be applicable for future projects of this nature:• Gather extensive research data on the area to

develop a good contextual understanding of thepeople and the places.

• Place the user and community at the centre ofthe project and through an inclusive processdevelop the solution with them. Listen to theusers, understand their needs.

• If appropriate use / adopt / adapt / apply thetechnology / principles that best fit the need. Inother words: adapt the scientific / tested best


practice principle to fit the project at hand.• Observe the users in action, see what subtle

principles they have invented to make their liveseasier or the way in which they prefer to use theproduct. Gain a good understanding of the sys-tems they have put in place to optimize theproduct.

• Design an appropriate solution that is sensitiveto the acceptance by the user. If necessary retainsome of the original aesthetics of the productthat your solution will be replacing. This is toallow the users to continue to respond / engage/ wish to use the product you propose.

• Resolve ergonomic and safety issues, designershave a responsibility to make sure the users aresafe at all times when interacting with their prod-ucts. Make sure the users will not harm them-selves through using the product.

• Capacity building and sustainable practice:design the product to be manufactured atsource. Empower communities rather than massproduce remote from users.

• Empower the manufacturer to continue todesign and develop the project even after theintervention has taken place. The manufacturersare in touch with the users and should thereforebe able to make the adjustments as requiredfrom interacting with their product users.

• Use locally available and recycled materials asfar as possible.

• Hand over the plans for the design solution to across section of local manufacturers to allowthem to manufacture the stove without needingto pay for the intellectual property.

Notes

1. The Programme for Biomass Energy Conservation(ProBEC), implemented by the German Organisationfor Technical Cooperation (GIZ), formerly known asGTZ, was an official SADC programme and the onlyone focused on basic energy. ProBEC ), and theUniversity of Johannesburg collaborated to establisha Stove Testing and Research Centre (SeTaR Centre),which is partially housed in the Department ofIndustrial Design. This research centre forms part ofthe support infrastructure for aspects of projects with-in the broader theme ‘Energy Research’ within theUniversity of Johannesburg and will add value to theuniversity’s mission to conduct relevant and usefulresearch for developing communities in the SouthernAfrican Development Community (SADC) region bytesting stoves intended for developing communitiesand offering design improvements for these stoves.

2. The Maputo Ceramic Charcoal Stove was an earlymodel of what is now called the Poupa Carvão(POCA) charcoal stove in which ProBEC and the

GTZ have since invested a lot more research anddevelopment effort and money (Ceramic mix, toler-ances etc).

3. ‘Sanlam is the sponsor of the Creativity for ProgressCompetition, which is run among South African aca-demic institutions. The theme for the competition is abetter life for people in informal settlements. It pro-vides an excellent opportunity for student groups andfaculties to come up with innovative concepts on howto improve their life in informal settlements.’ (Sanlam,2008)

4. The Manica Charcoal Stove Project was given greatinsight into the town of Manica and the issues ofdeforestation, the use of charcoal stoves in the townand details of the town and surrounding areas fromthe BA (Honours) mini thesis completed by Schalkvan Heerden in 2005. van Heerden lived in the townfor five years from 2002 to 2007 and continues tomaintain his link to the town through his involvementwith the local soccer club: Groupo Desportivo deManica. His research provides the background andgrounding required to give the designers the under-standing they required for this study. His connectionswithin the town and its people were also leveraged toassist with the research process and gain access to thelocal community.

5. From van Heerden, 2005: SWIFT, K. 1974. Mozam-bique and the Future. Cape Town: Don Nelson.

6. Refers to in this context as the amalgamation of vari-ous architectural styles in the region and how theseinfluenced each other. Luso – standing for Lusitaniaand the African mixed style.

7. United States Dollar (US$) / Meticais (Mtn) rate ofexchange calculated on 1 US Dollar = 35.30 Mozam-bique Meticais (September, 2010: www.oanda.com/convert/classic)

Acknowledgement

The author would like to thank Schalk van Heerden forhis invaluable contribution to the success of the ManicaCharcoal Stove Project. Further thanks are extended toVictor Bezuidenhoudt, John Harverson, Ross Nelson andTheo Olivier for completing the field research and testingfor the project. He would also like to thank NelsonVeremo, Shortstop Chikwandingwa and the membersand management of the Grupo Desportivo de Manica fortheir hospitality and assistance throughout the project.This project would not have been possible without theactive participation of the people of Manica Town.

ReferencesBezuidenhout, V., Harverson, J., Nelson, R. & Olivier, T.

(2008). The Manica Charcoal Stove Project –Research report for the design and development of amore efficient charcoal stove. Research report for theDepartment of Industrial Design. Johannesburg:University of Johannesburg. Unpublished manu-script.

Boztepe, S. (2007). User value: competing theories andmodels. [O] International Journal of Design, August2007 Volume 1 (2). Available at: www.ijdesign.org.

Bradnum, C. (2008). Manica charcoal stove project.


FADA Research Newsletter, December 2008, Issue11.

Blunck, M. (2010). Comments on the CDM programmeof activities ‘improved cook stoves for East Africa(ICSEA)’ Eschborn, Germany: Poverty-orientedBasic Energy Services (HERA) / DeutscheGesellschaft für Technische Zusammenarbeit (GTZ)GmbH. Available at:cdm.unfccc.int/filestorage/Q/U/M/QUMUW3OVANGJT9SPQ5IXQZ2F6EHTOP/Comments.pdf?t=Vkx8bWlzNGhwfDB4FhfeyyNxOIUj_P0wOD1c.

Carroll, J. & Rosson M, B. (2007). Participatory designin community informatics. Design Studies 28, GreatBritain: Elsevier Science Ltd.

Chidamba, C.T. (2010). Report on the impact assess-ment of the POCA (POupa CArvão) charcoal stove.Maputo: ProBEC.

Coughlin, P.E. (2007). Baseline survey of market andhousehold cooks. Maputo: EconPolicy ResearchGroup, Lda. And Program for Biomass EnergyConservation (ProBEC).

Coughlin, P.E. (2008). Field testing for ceramic stoves:survey results from three boroughs in Maputo andMatola. Maputo: ProBEC.

Ford, R. (2010). What Social Entrepreneurship CanTeach Social Design. [O] Available at: changeobserv-er.designobserver.com/entry.html?entry=15148.

Feldmann, L. & Brinkmann, V. (2007). Marketing inhousehold energy interventions – GTZ experiencesfrom different African countries. GTZ / HERA –Household Energy Programme. Johannesburg:Boiling Point, No 54, Pages 20-22. Available at:www.hedon.info/tiki-download_item_attachment.php?attId=73.

Kahmann, R. & Henze, L. (1999). ‘Usability Testingunder Time-Pressure in Design Practice’ in Green,W. S. & Jordan, P.W. (Eds.) Human factors in prod-uct design. London: Taylor and Francis.

Margolin, V. (2000). Building a Design ResearchCommunity. Proceedings of the Politecnico diMilano Conference, May 18-20, Milan: Politecnico diMilano.

PCIA (The Partnership for Clean Indoor Air) 2013.Accessed at: www.pciaonline.org.

Sanlam, (2008). Sanlam inter-university creativity forprogress challenge [O] Available at:web.up.ac.za/UserFiles/SANLAMINTER%20UNI-VERSITY%20CREATIVITY%20CHALLENGE.docSanlam Creativity for Progress Competition.

Van Heerden, S. (2005). Relative sustainability: The‘tragedy of the commons’, trees, institutions andenvironment in Manica, Mozambique. Mini disserta-tion submitted in partial fulfilment of the require-ments for the degree of BA (Hons) in theDepartment of Anthropology & DevelopmentStudies. Johannesburg: University of Johannesburg.

WBT (Water Boiling Test) (2009). The Water BoilingTest Version 4.1.2: Cookstove Emissions andEfficiency in a Controlled Laboratory Setting.Available at:www.pciaonline.org/files/wbt4.1.2_0_0.pdf.

Winiarski, L. & Still, D. (2001). Increasing fuel efficiencyand reducing harmful emissions in traditional cook-

ing stoves [O] Available at:www.hedon.info/docs/BP47-14-StillWiniarski.pdf

Interviews and e-mailsChikwandingwa, S. (2008). General discussion with

Shortcover Chikwandingwa, General Manager at theGrupo Desportivo de Manica and highly regardedmusician in Southern Africa throughout the field trip(all notes confirmed by Chikwandingwa).

Efficiency Testing, (2004). Email from Dr Phillip Lloyd.ERC, UCT; 25-10-2004.

Van Heerden, S. (2008). General discussion with theUniversity of Johannesburg, Corporate SocialInvestment Administration Assistant and GrupoDesportivo de Manica Project Manager throughoutthe field trip (all notes confirmed by van Heerden).

Veremo, N. (2008). General discussion with NelsonVeremo, English teacher at the Grupo Desportivo deManica throughout the field trip (all notes confirmedby Veremo).

Received 18 July 2011, revised 18 March 2013


the manica charcoal stove project

Documents