Friday, June 02, 2006

Design of Stoves for Use in Developing Countries...

Many of you may know by now that EWB-SFP has become engaged with efforts to improve the efficiency of wood burning cook stoves for IDP (internally displaced people - "refugees" who have not left their own country) in Darfur, Sudan. As discussed earlier in this blog, the distance that people need to venture to gather firewood is increasing all the time as the surrounding countryside is de-nuded, and this has led to problems that can be addressed by a more energy efficient cooking stove. This project is described at:
and contributions by EWB-SFP are getting underway - the "Tara stove" (an inexpensive sheet metal stove presently produced in India) has been altered by Prof. Ashok Gadgil's team (from Lawrence Berkeley National Laboratory, LBNL for short) to meet the local conditions and needs that they have researched there on the ground. This modified stove design is being tweaked further, even as I write, to make it easier to manufacture locally, it is now in a computer format that allows the design to be examined easily and modified, and we are at the point of manufacturing a few of this latest design so that they can demonstate it again in Sudan soon. And see how it can be further improved for production in small villages in the region.

The purpose of this post is to provide background information for those interested in learning more about the development of improved "biomass" stoves (fueled by wood and other natural materials) all around the world. The efficient stove problem has been well described (environmental, health, security, etc. issues) and researched/documented extensively; so much has been written and is available on the web. I'll try to distill here some of the very best resources into a shorter list than is found at any particular website, with just a few releantv details about each one. Dig deeper into any of these sites and you'll find much more than you want. Trust me, these are the best that can be found in one day with Google.

In these very links you'll find information about designs, calculations, experiences, efficiency testing, etc. for all kinds of stoves for the developing world - the Darfur/LBNL stove is a sheet metal design, and others discussed include masonary ones and those of mixed metal and masonary construction. The stove that we are working on should perhaps be considered as an emergency design - where some aspects have not yet been optimized in the interest of delivering something fast and inexpensively to an area in extreme need. There are severe time constraints if this project is to be started quickly (flexibility is the benefit of small groups), but the design can be expected to improve over time to improve its manufacturability in the local area, reduce the cost, and make it more suitable for the cooking conditions of the local people. It is extremely important to make this technology "appropriate", so we need to learn what resources are available locally and what is needed by the local cooks.

Enough background! My latest favorite general resource is:
and many of the links below are extracted from here, in a fashion that emphasizes the stove designs and experiences that might be most relevant to the Darfur need. For example, some very detailed on line design resources (almost book length!) described there include: - Improved Solid Biomass Cookstoves: A Development Manual, by UN-FAO. 125 pages of great information, all the way up to combustion science, heat transfer, and fluid flow calculations. This is stove science!

Similarly as good (each resource is different, and better than the others in their own way) is the website of the Renewable Energy Policy Project's (REPP) discussion group on Biomass Cooking Stoves:
where you will find loads of photos of stove designs and case studies - look at this first if you want immediate gratification! Four years worth of discussion are archived here.

Within this site there is a vast number of other links, including:

Max Chen reminds us that this site (and the CD/book offered there) reviews published books on improved cookstoves (and a billion other AT topics):

The web almost has too much information! Increasingly specialized sites and discussions hopefully help people find only what they need, instead of becoming mired in excess - even a problem for somewhat narrow topics like AT. Here are some examples of books reviewed in the AT Sourcebook:
  • Technology, Markets and People: The Use and Misuse of Fuelsaving Stoves
  • Burning Issues: Implementing Pilot Stove Programmes, A Guide for Eastern Africa
  • Modern Stoves for All
  • A Woodstove Compendium - empasizes the role of engineers
  • Helping People in Poor Countries Develop Fuel Saving Cookstoves
  • Cookstove Handbook
  • Testing the Efficiency of Wood-Burning Cookstoves: International Standards
  • Wood Conserving Cook Stoves: A Design Guide
the books are about far flung places like Africa, Guatemala, Sri Lanka, Nepal, and Java - each country has unique needs and resources, so requires different stove designs.

Speaking of different countries, this site lists an amazing volume of stove information from online discussions over the years - page after page of just detailed stove links, describing research projects country by country (+55 countries)!:

One of my very favorite NGOs (a major goal of theirs seems to be preserving and transferring the best existing information around the world - to me a most efficient method for change) is ITDG - formerly the Intermediate Technology Development Group but now called Practical Action. If only for variety, take a look at some IDTG sites - over the years they have published some of the best information, in huge quantities:
and their book publishing arm is one of their strong suites - they have many pages of books of interest to us under their "energy" heading:
  • Stove Maker, Stove User - fuel-efficient stoves in Sri Lanka
  • Stoves for People - disseminating stove knowledge internationally
  • The Kenya Ceramic Jiko - a manual for stovemakers
  • The Stove Project Manual

For those who like wikis this is just an AT one (the stove entry needs to grow - volunteers?):
And I can't resist adding this link to the ultimate western world stove research discussion site - for lightweight backpacking stoves only though. Still worthy of note for our work:

In summary, I hope that an examination of some of this information will lead you to believe that this Darfur stove project is based on an immediate need which is not being adequately addressed by other aid organizations. The design of the stove, the proposed local production model, the efficiency and measurement approach, the performance in Darfur cooking trials, and the phased approach are meant to improve our chances of meeting real needs by continuously improving the design... and almost all seem like "appropriate technology" for this situation to me. Towards this goal, we expect that all manufacturing of the stove will be near the IDP camps ASAP, so that users can quickly contribute to the stove improvement process.

"Any third-rate engineer can make a machine or a process more complex; afterwards, it takes a first-rate engineer to make it simple again."
E.F. Schumacher, author of Small is Beautiful, and a founder of ITDG/Practical Action

In April reader SL commented on a blog posting here:
Isn't designing appropriate technology of secondary importance to building local capacity to innovate technological solutions to local problems?

I just get tired of these types of programs because they seem to focus on designing solutions to problems that local NGO's understand better than western engineering students.

What is your position on these issues?

I (Charlie) open this topic up for discussion and start it by observing that it appears that the smaller the aiding organization the more likely it seems as if the project will actively seek the input of local people, and try to follow their recommendations. International develoment dollars too often go to western "experts" instead of the local economy, so I believe that efforts like this one - with no ideology, funding or salaries, assumptions and pre-conceived notions, and with a healthy dose of on the ground work to identify the real problems and needs - are an improved way of trying to improve conditions in very local regions. I am a beginner at development projects but have traveled often in places with extremely low per capita incomes. I have seen that happiness has little to do with wealth, and western misperceptions about local conditions (variety of diet, perceived water quality, comparison of sanitation with our standards, living situations, employment levels and cash earnings, lack of modern amenities like electricity, etc.) can lead to development project proposals (and spending) which do not meet the real needs of people. Who are we to try to manipulate their "quality of life" without first being in their shoes? As the commenter implies, local experience is everything - listen to people, live with them if you can, understand their history and available resources, speak the language if that is what it takes, ask about what NGO efforts already have helped and those which have not, and prioritize your ideas of their needs only afterwards. You might find that addressing core issues like very basic health care, food security, and environmental protection (all using local resources) will go a lot further than inserting alien technologies that we think they need. Appropriate Technology projects in particular hopefully tend to work this way. I hope that the Darfur stove project, and all EWB-SFP ATDT projects, will spend extra time on the ground working with local NGOs just so we don't make the most common mistakes.