Cook stove

Stove manufacture in Senegal.

In cooking, a cook stove is a very basic stove heated by burning wood, charcoal, animal dung or crop residue. Cook stoves are the most common way of cooking and heating food in developing countries.

Developing countries consume little energy compared to developed nations; however, over 50% of the energy that they do use goes into cooking food. The average rural family spends 20% or more of its income purchasing wood or charcoal for cooking. Living in the city provides no refuge either as the urban poor frequently spend a significant portion of their income on the purchase of wood or charcoal.

Besides the high expense, another problem of cooking over an open fire is the increased health problems brought on from the smoke, particularly lung and eye ailments, but also birth defects. Replacing the traditional 3-rock cook stove with an improved one and venting the smoke out of the house through a chimney can dramatically improve a family’s health.

Deforestation and erosion are often the end result of harvesting wood for cooking fuel. The main goal of most improved cooking stoves is to reduce the pressure placed on local forests by reducing the amount of wood the stoves consume. Additionally, the money a family spends on wood or charcoal translates into less money being available to be spent on food, education, and medical care; so an improved cooking stove is seen as a way of boosting a family's income.

Three stone cooking fire

A Guatemalan woman cooking corn tortillas with a traditional comal over a 3 stone wood fire.

The traditional method of cooking is on a three stone cooking fire. It is the cheapest stove to produce, requiring only three suitable stones of the same height on which a cooking pot can be balanced over a fire. However, this cooking method also has many problems:

• Smoke is vented into the home, instead of outdoors, causing health problems. According to the World Health Organization, "Every year, indoor air pollution is responsible for the death of 1.6 million people - that's one death every 20 seconds."^[1]

• Fuel is wasted, as heat is allowed to escape into the open air. This requires more labor on the part of the user to gather fuel and may result in increased deforestation if wood is used for fuel.

• Only one cooking pot can be used at a time.

• The use of an open fire creates a risk of burns and scalds.^[2] Especially when the stove is used indoors, cramped conditions make adults and particularly children susceptible to falling or stepping into the fire and receiving burns. Additionally, accidental spills of boiling water may result in scalding, and blowing on the fire to supply oxygen may discharge burning embers and cause eye injuries.

Improved stoves and other measures

The World Health Organization has documented the significant number of deaths caused by smoke from home fires.^[3] The negative impacts can be reduced by using improved cook stoves, improved fuels (e.g. biogas, or kerosene instead of dung), changes to the environment (e.g. use of a chimney), and changes to user behaviour (e.g. drying fuel wood before use, using a lid during cooking)."^[1] Improved stoves are more efficient, meaning that the stove's users spend less time gathering wood or other fuels, suffer less emphysema and other lung diseases prevalent in smoke-filled homes, while reducing deforestation and air pollution. Some designs also make the stove safer, preventing burns that often occur when children stumble into open fires. Some of the new stove designs are discussed below.

' ' Dos por Tres Stove' '

=== Brick and Mortar Stove ===

A variety of new brick and mortar stoves have emerged. Most of the new designs incorporate a combustion chamber found in a rocket stove. By confining combustion to an insulated and enclosed area, the stoves increase the core temperature and thereby achieve more complete combustion. This allows a smaller amount of fuel to burn hotter, while producing less ash and smoke.^[4] Several stoves with similar features have emerged, often varying only slightly from one another. The Justa Stove is a simple biomass stove built around an insulated, elbow-shaped combustion chamber which provides more intense heat and cleaner combustion than an open fire, meaning that it consumes less fuel than a three-rock stove.

An improved Justa stove jointly developed by the non-profit Proyecto Mirador and the Aprovecho Research Center called the Dos por Tres is being disseminated in Honduras with more than 20,000 stoves installed as of 2011. The Dos por Tres has been registered as Project 690 and certified by the Gold Standard Foundation to reduce greenhouse gas emissions by 2.7 tons per year. All Proyecto Mirador documentation related to proof of these reductions can be viewed on the Gold Standard Project registry [2]. The co benefits of the Dos por Tres are highlighted in this video ^[5] and construction of a Dos por Tres can be seen here ^[6]

The Justa stove^[7] has been deployed in Honduras by Trees, Water & People and AHDESA, for which they jointly won an Ashden Award in 2005.^[8] The Eco Stove and the Patsari stove share common benefits with the Justa Stove, and are also used in Central America. Their proponents claim that these stoves use approximately 1/3 of the fuel required by traditional three stone stoves, lessening the daily labor devoted to gathering wood and also preventing deforestation. At the same time, it employs a stove pipe flue to vent fumes through the roof.^[9] This almost eliminates cooking smoke within the home, preventing respiratory problems for the users. Various groups have run programs to provide such stoves, or encourage production of stove making facilities, including certain Rotary Clubs, Trees, Water and People,^[10] and organizations aimed at preserving wildlife by preventing deforestation.

Lorena adobe stove

A predecessor to the Justa/Eco/Patsari stoves was the Lorena adobe stove. It was designed as a simple-to-build cook stove for use in Central America, one that could be manufactured locally of local materials. The name of Lorena stove comes from the combination of the two Spanish words lodo and arena (meaning mud and sand) as the stoves are basically a mix of the two. It became very popular in Central America, with anecdotal evidence suggesting that it is the most popular improved cooking stove in the region. The Lorena stove is an enclosed stove of rammed earth construction, with a chimney built onto it.^[11]

The Lorena stove was designed with the mistaken belief that rammed earth would act as insulation; there was a basic misunderstanding of the difference between mass and insulation. Good insulation resists the passage of heat; thermal mass does the opposite, it absorbs heat. Testing has shown that the rammed earth used in the Lorena stove absorbs heat that should be directed toward cooking.

The designers, Aprovecho, now state: "The Lorena has been tested over the years by many researchers and has generally been found to use more firewood than an indoor open fire. The stove has other attributes. Its chimney takes smoke out of the kitchen and it is well liked. It is pretty and a nice addition to the house. It is low cost and can be repaired and even built by the home owner. But, it is not a fuel saving or low emission stove". In later designs, the rammed earth has been replaced with thermal insulation, such as pumice or ash.

Kenya Ceramic Jiko

From the beginning of the appropriate technology movement, one of the principal goals has been to create an affordable stove that was more efficient than the universally used three stone cooking fire. Of all the improved stoves, the Kenya Ceramic Jiko (KCJ) has been the most widely accepted to date, having become a standard item in most homes in Kenya and neighboring countries in East and Central Africa.

Charcoal is the standard cooking fuel in East Africa. Traditionally it was burned in a metal stove or “Jiko” as stoves are called in the Swahili language. The KCJ is simply the traditional Jiko mated to a ceramic liner, producing a stove that is at least one fourth (and up to 50%) more efficient than traditional all-metal alternatives, costing only $2 to $5. The initial model has a distinctive shape, differing from the traditional cylindrical jiko, with the top and bottom the same diameter, tapering at about 30 degrees to a waist.

There are many variations on the same theme that can be found in Kenya and other areas of East Africa. Some are designed to be more robust than the original KCJ, and some such as the Upisi are designed to burn wood instead of charcoal, while others are built into the home, and remain stationary. File:C:\Users\user\Downloads\sundowner cafe, mara, baking bread.JPG.jpg The Energy Efficient Charcoal Oven is a new innovation that has been developed and marketed by one of the initial disseminators of the KCJ; Dr. Max Kinyanjui, they are sold in supermarket chains around east Africa and allow people without access to electricity or gas to bake bread on a commercial or domestic scale using very little charcoal. Improved stoves also reduce the amount of forest cover lost and are a viable greenhouse gas reducer in addition to providing employment to a large number of sheet metal artisans.

Sanjha Chulha/Earth Stove/Surya Stove

Since 1999, an engineering company named Nishant Bioenergy (P) Limited in North India is conceiving, designing, fabricating and selling patent pending biomass briquette cook stoves. These are commercial cook stoves and are designed to burn biomass briquette. Biomass briquettes can be made from any farm or forest residues with or without binders.

The advantages of the stoves include sturdiness for heavy cooking utensils, lower cost of operation, ease of use, safe operation and the fact that they are carbon neutral. They manufacture many models like Sanjha Chulha and Earth Stove. Capacities are from 16000 KCal/Hr to 200000 KCal/hr. Earth Stoves are being used by a variety of people cooking food for 50 people to 50,000 people per day. As of January, 2010, they have installed around 355 stoves (total installed capacity is more than 13 MWh). Projects under execution are worth 3.5 Million Kcal/hr. They also have five franchises in western and southern states of India and are planning two more to spread the technology. Earth Stove based NISHANT STEAMER is also a great hit with college/school hostels. At some places savings are more than 75%.

Recently company has developed new technology named SURYA STOVE. Surya Stove technology is one of a kind as it runs on powdered biomass like saw dust (any biomass can be used provided it is dry (has a moisture content at or less than 10%) and is pulverised to 8 mm mesh ). The stove has automated fuel feed and ash cleansing system. It has a temperature controller to pre-set the temperature of the cooking/frying medium. It is especially designed for the frying needs of the ready-to-eat food industry. The company has planned to launch a nationwide project of 1000 such stoves duly linked with fuel supply chain with the assistance of local village based bio refinery.

The company has won national and international recognition for their unique efforts. Awards include the Ashden Award in 2005,^[12] PCRA Award -2001, and UN promising practices-2006.

Prefab Stoves

The Ecocina stove is manufactured at a central location from cement, pumice, and ceramic tiles. It resembles a large flower pot, with a steel cooking surface which can also receive a pot.^[13] It is the creation of a volunteer worker who noticed the high number of respiratory illnesses and burns on patients in Guatemala. It is actively produced in several countries, including Guatemala and Honduras. Unlike its brick and mortar counterparts, the Ecocina stoves have no flue and are manufactured in a backyard factory. They are then placed in a home on top of a table or similar raised surface. Again, as with their brick and mortar counterpart, the Ecocina stove employs a rocket stove combustion chamber and promises the same reduction in consumption of fire wood and reduction in fumes emitted into the home. It also remains cool to the touch, preventing burns.

Turbo Stoves

Some new metal stoves employ turbo charging features, air pressed into the stove or swirled, dramatically increasing the efficiency of combustion. Two such stoves are the Turbococina, developed in El Salvador, and the Lucai Stove, developed by World Stove. While the Turbococina promised dramatic results by employing higher pressures to lower combustion temperatures, its high cost of production (stainless steel) and its use of electricity have prevented it from going into production. At present, it does not appear to be economically viable. The Lucia Stove also employs swirling air patterns to change combustion, and has been economically produced. It is marketed by World Stove as one part of a larger environmental solution, because it captures carbon and thereby reduces the amount of carbon in the atmosphere from cooking. It produces Biocarb that is then recycled back to the soil.^[14]

Standard approaches to conserving cooking fuel

Almost all rural and many urban families in Latin America rely solely on wood for their cooking needs. In most of Africa charcoal is the standard cooking fuel. In other places it can be a mix of the two, or alternatively like families on the Great Plains during the 1800s animal dung may be in common use if it is the only thing available.

There are three places in the cooking process where fuel can be conserved; the fuel, the stove, and the cooking pot. The greatest gains come not from the stove itself, but from how the heat the stove produces is used; paying attention to the pot rather than the stove results in the greatest fuel savings. In fact, fuel efficiency in a stove is usually much more affected by heat transfer to the pot than it is by improving combustion efficiency.

• The first way to reduce the amount of fuel a family consumes is simply to use a cooking lid while cooking, which by itself reduces fuel consumption by 40%. This simple change will normally save more fuel by itself than switching to an improved stove.

• The second strategy is similar to the first; use a larger cooking pot. Larger pots are more energy efficient than smaller ones and wide shallow pots are more efficient than tall narrow ones.

• Last, when cooking for a family, switching from a stove that has room for only one pot to cook at a time, to a stove where two or more pots can cook at once will often raise efficiencies by up to 40%.

In developing countries, families who rely upon wood for cooking have three ways of obtaining it. They can scavenge the areas where they live for firewood, purchase it from a firewood dealer, or grow their own. In most villages there is a lack of harvestable firewood in the surrounding area, and so most of the wood used is brought into the village and sold through a dealer. Those who cannot afford to buy firewood are often forced to travel several miles to acquire wood. Some families have obtained self-sufficiency by maintaining a living fence, or growing a woodlot near the family home.

Smokeless and wood conserving stoves

Smokeless stoves and wood conserving stoves are terms used to describe stoves designed for developing country settings to reduce the health impacts of smoke from open fires inside dwellings. It is generally claimed that the new designs burn the wood (or other fuel) more efficiently. Important features may include a pipe (chimney) to vent the smoke and a different chamber design.

There are various designs, such as the Lorena stove and the ONIL Stove which uses mortar-less concrete blocks in its construction and costs $150 USD per stove.^[15] Another design is the Berkeley-Darfur stove that reduces smoke and is twice as efficient as a clay stove, with the goal of reducing the need for women to leave the camps in search of wood.^[16]

The most fuel-efficient type of cooker is the solar cooker, which uses no fuels of any kind. These devices of course require clear sunlight, but they are practical in many of the sunny regions of the world^[17].

See also

• Envirofit
• Indoor air pollution in developing nations
• Lo Trau
• Multifuel stove
• Portable stove
• Rocket stove
• Shichirin

References

1. ^ ^{a b} Indoor air pollution and health - World Health Organization fact sheet.
2. ^ "Health Benefits". The ONIL Stove. http://www.onilstove.com/benefits.htm. Retrieved 2007-04-13. 
3. ^ [1]
4. ^ [Design Principles For Wood Burning Cookstoves http://www.stovetec.net/us/images/stories/pdfs/DesignPrinciplesForWoodBurningCookstoves.pdf]
5. ^ [You Tube Video on Carbon Offsets Plus http://www.youtube.com/watch?v=2uMvS1a0Hyw]
6. ^ [Proyecto Mirador: Building an Estufa Dos por Tres http://www.youtube.com/watch?v=FabOfSw9_7w]
7. ^ [YouTube Video on Justa Stove http://www.youtube.com/watch?v=dLlcJWXCHpQ]
8. ^ Justa stove wins Ashden Award
9. ^ [Diagrams and Plans for Justa Stove http://www.green-trust.org/freebooks/justastoveplans.pdf ]
10. ^ [Trees, Water and People http://www.treeswaterpeople.org/stoves/info/slideshow_stovemodels.htm]
11. ^ bioenergylists.org
12. ^ Nishant Bioenergy won Ashden Award
13. ^ [YouTube Video on Ecocina Stove http://www.youtube.com/watch?v=STt1I8gRkp0]
14. ^ [YouTube Video on Lucia Stove, http://www.youtube.com/watch?v=STt1I8gRkp0
15. ^ "The ONIL Stove". HELPS International. http://www.helpsinternational.com/programs/stove.php. Retrieved 2007-04-14. "Each stove costs only $150..." 
16. ^ "What is a Darfur Stove - Darfur Stoves Project". http://www.darfurstoves.org/darfur-stove. Retrieved 2008-07-14. 
17. ^ "Solar Household Energy". http://www.she-inc.org/index.php. Retrieved 2011-07-27. 

External links

• Improved stoves at Appropedia, an anti-poverty and appropriate technology wiki.
• Partnership for Clean Indoor Air
• Biomass cooking stoves
• Aprovecho stove research
• Rethinking the Latin American Cookstove by Dean Still. A critical assessment of Lorena stoves & other new "improvements", and a discussion of how to improve the design.
• Final Report for "Lorena Stoves to Protect Lungs and Forests" - The Virtual Foundation
• Onil Stove - Community of Christ Health Ministries Association.
• Burning Issues - A project of Clean Air Revival, Inc.. Promotes awareness of the negative health impacts of wood smoke.
• BioEnergy Lists: Biomass Cooking Stoves
• Holey Briquette Gassifier Stove Development - Richard Stanley, Kobus Venter 14 August 2003, on BioEnergy Lists
• Asia Regional Cookstove Program (ARECOP)
• What Makes People Cook With Improved Stoves
• Ashden Awards case studies on fuel-efficient stoves in developing countries
• The Gold Standard Foundation (Certification of Carbon Offsets)