The Basics of Wood Burning Stoves: A Case for Standards or Rating Systems?

Many people interested in better stoves know something about fire, smoke, health and new ideas.  However, to explain these on a more fundamental level that is understood by all can be difficult.  Therefore to explain the relationship between health and smoke, I turn to the late comedian Steve Allen who said that “Asthma doesn't seem to bother me any more unless I'm around cigars or dogs. The thing that would bother me most would be a dog smoking a cigar.”  For those who are promoting stoves innovations, I quote Mark Twain who says “The man with a new idea is a crank until the idea succeeds.” 

More seriously, I recently came across this nice brochure on space heating stoves that has been published by the California Environmental Protection Agency.  I was struck by this brochure because in a very simple way it publicizes the issue of smoke and health, the need for standards,  the basic principles of combustion and even the alternatives to wood stoves including gas and electricity.    These are many of the same issues that the clean cooking community today is attempting to communicate to the general public.  This brochure highlights the fact that improved heating stoves in the United States and other developed countries are now very efficient and burn very cleanly compared to past stoves.  But this was not always the case. 

Painting of Old Heating Stove in School

On a personal note, I can remember old coal stoves used to heat "temporary" small classrooms built to accommodate a sudden rise in student populations.  These "potbelly" coal heating stoves were similar to the wood burning stove in the picture.  At the time in western Pennsylvania coal was king and this was at the very end of the time period when people would heat with traditional coal stoves.  Was it smoky? Yes. Was it energy efficient? No. Did it give good even heat?  No.  Wast it durable? Yes. Was it safe? Yes. Was it cheap?  Yes.  Now of course schools are heated with modern systems. 

Even now there are legacy fireplaces and wood stoves that burn warmed air in the house which in turn draws in cold air from the outside.  Thus, the old traditional space heating stoves in developed countries are somewhat analogous to open cooking fires in developing countries.  The rather important exceptions are that the cooking fires and traditional cookstoves in developing countries typically are built of local materials by those who use them and they also do not have chimneys.

Improved Biomass Stoves For Bangladesh: Practice and Promise

Bangladesh has a better record in addressing rural energy issues than most countries. They have a very aggressive rural electrification program that is based on rural electric distribution cooperatives. There is an award winning program for promoting solar home systems in offgrid regions. Yet as we documented in our report on Bangladesh’s Rural Energy Realities the country has not been as successful in promoting ways to alleviate problems associated cooking with biomass energy on rudimentary stoves. This is in spite of the fact that bioass energy is so scarce that leaves and grass account for 15 percent of total rural energy use.

Bangladeshi Woman Cooking with Child:  Photo Prabir Mallik

Recently there has been a new report released on Improved Cookstoves and Better Health in Bangladesh.  For a preview there is a online version of the report at the bottom of this blog.  This report is provides a new twist to work on improved or advanced biomass stoves. Not only does the report review programs in Bangladesh, but it also draws lessons from successful international experiences and water and sanitation programs.  The picture to the right has graced the cover of several reports and it was originally taken by Prabir Mallik on one of the assignments that took place during the project.

Many of the existing programs in Bangladesh are promoting what we have called in previous blogs artisan stoves. There are not too many successful examples of artisan programs in the world. Most of the programs that flourished have had at the very minimum manufactured parts as was the case in China and Guatemala.  A promising new development is that within the last couple of years Grameen Shakti (see text below the break) has recently entered the picture in Bangladesh to promote improved stoves, and they are manufacturing some of the parts such as stovepipes and grills, but the firebox of its stove is still made from local materials such as clay or mud.

What are the recommendations of the new Bangladesh report? The main recommendation is to move towards higher quality stoves that are proven to be more energy efficient and lower household air pollution. Here are some key quotes from the executive summary.

Lessons from the international programs emphasize the need for a wide range of efficient stove designs tailored to user requirements as a prerequisite for program success. They should have proven efficiency, the ability to reduce indoor air pollution, and good durability and safety. Further, the viability of the program in the long term often depends on strong commercial approaches to promoting stoves. Targeted marketing has also been seen to be an effective strategy; stoves should be marketed to households facing fuelwood scarcity or high costs of purchasing wood, as they would be the most likely group to benefit from improved stoves, at least in the initial stages of a program.

The review of the status of improved stove programs in Bangladesh, along with the best practices from around the world, leads to several recommendations for consideration. One clear message is the need for a more unified program without diminishing the creativity of the various groups advocating improved stoves in Bangladesh. In fact, creativity and a wide variety of approaches should be encouraged. The government’s role is not necessarily to be the main actor, but rather to facilitate a process that promotes variety, improved durability, better safety, and greater efficiency of improved stoves.

Promoting Solar Home Systems and Improved Biomass Stoves: A Comparison

Solar PV Adoption by Herders, Qinghai, China
Photo by China REDP Team

Over the past 15 years strategies for solar home system promotion have moved from a niche activity to the mainstream. Recently I have been thinking that there are quite a few similarities in the obstacles that were faced by solar homes system in the early years and those confronting the new improved biomass stoves today. I thought it might be a good time to explore what we have learned over the years, and what lessons might be relevant for scaling up the adoption of improved biomass stoves.

Both solar home systems and improved stoves are used primarily for household energy services such as cooking and lighting. They both provide significant improvements compared to the kerosene lamp or an open fire. Both devices also involve fairly large initial costs that are barely affordable to the majority of populations in developing countries, but the cost to operate them is fairly low. Solar home systems cost on the order of US $200-$300 and the new generation of improved stoves range from US $10 to $70 or more. As the old joke goes “Solar (read that renewable) energy is free, but it ain’t cheap.”

 

Today solar home systems are considered fairly mainstream and adoption levels though still somewhat limited are rising quickly in many countries. With the exception for the older large programs such as china, progress is being made by improved biomass stove programs, but they also have quite a long way to go to be accepted on a large scale in more countries.

Much more below the break....

Comparative Cooking Costs in Developing Countries

By Douglas Barnes and Keith Openshaw

Kerosene Lamps and Stoves, Hyderabad, India by D. Barnes

Recently we have just reviewed many of programs for improved stoves in developing countries, and we were quite surprised to find that there were few analyses of comparative cooking costs. In the glory days of country energy assessments comparing the cost of cooking to enlighten energy policy makers was very common. Today we stress energy efficiency, combustion, emissions, and carbon. However, if people are going to adopt these stoves the comparative cooking costs are an obvious important place to start. Keith Openshaw who has extensive experience with improved stoves is a coauthor of this posting. 

To revive this lost art, we will explain the steps for calculating comparative cooking. The first step is to assemble the necessary data. This includes:

• Cost of the stove;
• Lifetime of the stove;
• Efficiency of the stove;
• Price of fuels used burned by the stove including wood or other biomass fuels;
• Fuel collection hours for biomass fuels;
• Quantity of fuel consumed in the household per month; and
• Average wage of agricultural workers.

One caveat is that the comparative costs in this analysis are hypothetical because they assume that families cook exclusively with one fuel. Also, we use world market prices and average fuel consumption levels as defined by many different household energy surveys. Thus, these figures can be considered as typical but they do not relate to any one country due to various policies to tax and subsidize household fuels. They at least give us some perspective on the comparative costs of cooking in developing countries.

For much more continue below....

Improved Stoves in Developing Countries by the Numbers

Nepal Improved Stove by Simon de Trey White WWF-UK

There are 3 billion people in developing countries that rely on solid fuels for almost all of their cooking. The question can be asked how many of these over 800 million households cook with an improved stove? The answer comes from a new study by the World Health Organization (WHO) and the United Nations Development Programme (UNDP). Like any good mystery story you will have to skip to the end for the answer. All I will say is that the results may surprise you.

Before turning to the numbers, it is important to define an improved stove, and this is actually quite a contentious subject among specialists. The original programs were developed during the energy crisis of the 1980s and stoves were developed mainly to conserve biomass fuels. So energy conservation is the first definition. During the 1990s the literature on indoor air pollution was starting to link smoky stoves and health issues. At the time it was accepted that you need a chimney to remove smoke from the house. Thus energy conservation and smoke removal became a popular mandate. More recently in the last 10 years there is beginning to be evidence that the pollution from incomplete combustion of biomass energy might be the main health issue. Chimneys simply move the smoke to the outside only to drift back indoors. Now let’s add to this mix climate change and green house gases that must be taken into consideration. The demands on the humble biomass stove seem to grow and grow.

More below....

Facing Rural Energy Realities in Bangladesh

Adult Literacy Class, Bangladesh by Shehzad Noorani

People often forget that once Bangladesh was close to being the poorest country on the planet. Things certainly have changed in recent years. Bangladesh has always had policies for open trade that have helped the country become an exporter of manufactured goods, much of which has resulted from allowing investments by multinational firms.  Generally economic growth has been very positive in recent years.

The country also has a very ambitious and successful grid rural electrification program that was modeled after the USA rural electric cooperatives which is considered a “best practice.” Even for those rural households distant from the electricity grid, since 2002 there has been a very successful rural energy fund that is administered by a government bank. This fund along with prominent non-governmental organizations such as Grameen Shakti (part of Grameen Bank) and BRAC have been very active in promoting solar household systems for basic electric lighting and communications services for those out of reach from the grid electricity system. In recent years they also have been expanding to other rural energy technologies such as biogas and improved cookstoves.

Much more below....

New Generation Wood Stove Evaluation in Dabaab Kenya: Review Series

I just read a very fascinating report called Evaluation of Manufactured Wood-Burning Stoves in Dabaab Refugee Camps Kenya by the Berkeley Air Monitoring Group. This report compares the performance of many of the stoves that were mentioned in a previous post on next generation stoves. As part of this blog, from time to time I will provide a brief review of interesting studies or conferences. This is not meant to be a peer review, but rather the remarks will be my own personal views. Others can express their opinions by commenting on these review postings.

This study reminded me that measuring the efficiency of improved stoves is not a simple task, but it is quite necessary. Often there are evaluations of single stove interventions, but comparative reviews are not as common. Testing methods actually have been a point of great contention and debate because some favor certain types of stoves over others. Such a lack of objective information or comparative testing results has been hampering improved stoves in developing countries for many years. Millions of dollars are given for stove programs and the monitoring and evaluation is often not very credible.

This study actually lays out its methods very clearly describing the testing environment in detail. There also were focus discussion groups with the cooks, a research technique that is highly recommended and often lacking in other work on stoves. The technical part of the study evaluates multiple manufactured stoves using a method called the controlled cooking test. Under this test the same amount of typical local food is cooked with measured amounts of fuelwood. The results are reported in kilograms of the fuelwood required for standardized cooking of one kilogram of food. Again, this is obviously a contrived environment, but it is a standard method that has been used for more than 25 years.

See more below.

Cooking with LPG: Climate and Poverty Issues

What is the largest improved stove program in the developing world? The answer may surprise you. It is the Liquid Petroleum Gas (LPG) stove. The use of LPG worldwide has been growing for many years. It is not a renewable fuel like biomass energy, but it is clean burning and provides much greater efficiency than even the best improved biomass stoves. For those not familiar with LPG, it is quite similar to propane.

Retail LPG Use in India in Millions: Industry Source

LPG is quite commonly used in urban areas of developing countries and is becoming increasingly common in rural areas. In India alone since 1985 the petroleum industry reports that over 100 million households have switched from other cooking sources to LPG. Today even close to 20% of rural household are using LPG mostly for quick heating such as water boiling, and this amounts to about 30 million households. Not only is LPG subsidized in India, but it has become more widely available over the years.

India has had an aggressive LPG promotion campaign for years and just recently announced that there will be a program to provide free stoves to households below the poverty line. The subsidies no doubt are expensive for the government and as the program continues to expand one can question whether such subsidies are justifiable given the ready acceptance of LPG by the mostly high and middle income consumers. But one also might just imagine the positive health impacts of the widespread substitution of LPG for fuelwood. Cooking with LPG gives off minimum pollution and alleviates indoor air pollution.

LPG Cooking in Hyderbad India: by D. Barnes

One little understood fact is that LPG is used mainly by middle to high income families, but it also has indirect impacts on poor urban households who do not even use it. Why is this? The main reason is the pattern of dynamics of energy pricing. Obviously high taxes on LPG raise its overall price and conversely subsides lower the price. The price of fuelwood for cooking quite often mimics price of LPG or kerosene in large urban areas after taking into consideration energy efficiency. Poor people in urban areas generally purchase biomass fuels such as fuelwood or charcoal, so high LPG prices mean high prices for biomass energy. The poor spend quite a bit of their income on energy; it can be as high as high as 15 to 20 percent. Thus, the price of biomass energy is obviously very important for their welfare.

Concerning climate change, encouraging the substitution of LPG for biomass fuels actually may be a winning prospect. It actually takes just over 11 kilograms of wood to provide the same cooking heat as one kilogram of LPG due to higher energy content and greater efficiencies of gas stoves. After some further conversions, for the same cooking task wood burned in open fires actually gives off 4 times more CO2 compared to LPG. It is true that some wood is from renewable sources, but do we really know how much? Also, is it really relevant? Perhaps, but the CO2 is going into the air regardless of its source.

This also does not mean that we should give up on making biomass stoves that are less polluting and more or efficient (see previous blog on new generation of improved stoves). Some new stoves give off levels of pollution that similar to using LPG. There is also a role for cooking with other fuels and technologies such as biogas or perhaps even alcohol in developing countries.

The ultimate goal is to alleviate energy poverty and there are many ways to do it. This might even include the promotion of LPG for cooking. What do you think?

poll by twiigs.com

For more continue reading below.

Improved Biomass Stoves: The Next Generation

There is a new sheriff in town. Today around the world there is an entirely new and innovative variety of improved stoves that are being manufactured in factories or workshops and sometimes backed by large international companies. These new types of stoves generally are made of quite durable materials that will last for 5 to 10 years or even longer and some come with guarantees. The goal of the marketing of these new stoves is to improve energy efficiency of cooking, to lower indoor air pollution, and to reduce labor or cash expenses required for cooking for the poorest half of the world’s population. The idea is to supply the nearly 3 billion people around the world that still use biomass energy with a stove that that is more modern and efficient than the traditional ones that they now use. Will these new stoves bring order to the wild west of improved stoves programs characterized by hundreds of models made out of vastly different local materials and produced by local artisans?

Traditional Stove in India: Photo by S. Desai

Stoves have existed since the beginning of human history. They have come in various sizes and styles, having been adapted to myriad cultures and food preparation methods. As society has progressed, more sophisticated stove models have been developed. Today’s modern kitchen reflects the many types of standardized and specialized cooking devices available from coffee and tea pots to toasters and gas cooktops. In contrast, the poor in developing countries still burn biomass energy in what amounts to open fires. The smoke produced by these primitiave stoves has been associated with a number of diseases, the most serious of which is acute respiratory illness such as bronchitis and pnemonia.

Envirofit Stove Model G-3300 in India: Photo by Envirofit

The development of improved biomss stoves has witnessed several overlapping stages over the last 30 years and today there are actually three types of programs around the world. One type of improved stove is locally made by small businesses or the even those in household members after they trained. Such stoves are very inexpensive at less than 10 dollars each and sometimes even less than 5 dollars. These artisan-made stoves provide relatively good performance when new, but performance degrades over the short one or two year live of the stove. The second type of stove involves manufactured parts, which are assembled on site with local materials. These stoves are still inexpensive but are a bit more expensive and more durable than the artisan stoves. There will be a later blog on these two types of stoves.

Stovetec Stove: Photo by Aprovecho

The competition is heating up for the “next generation” of stoves that are manufactured in their entirely in factories and workshops world. They include efficient biomass stoves, alcohol stoves, stoves that use pellets, and others. Some of the world’s largest companies have become involved including Shell Foundation, Bosch Siemens, Phillips, British Petroleum and others. There are two interesting examples for wood stoves including the Envirofit stoves and the Stovetec produced by Aprovecho. Others innovations include the Worldstove, First Energy’s Oorja Stove, Gaia’s Dometic (Gaia project), Bosh-Siemens Protos stove, the Onil stove in Guatemala, and the Justa stove in Honduras. A very interesting new initiative by the Government of India endorses the concept of manufactured stoves and implementation is in the planning stages.

The international donors have been slow to embace or support these new generaton of stoves and admittedly this is still an incomplete picture. However, it may just take some time for the realization to set in that such programs can probably be as important as increasing electricity access in terms of improved health and quality of life such as less fuel collection, shorter cooking time, reduced releases of carbon, and less pressure on local forests.

Its nice that there is more international competition in developing new products. However, the question is should there be more interational attention to this problem?

More resources below.