Thursday, April 21, 2011

Installing the ONIL Stove in Guatemala

Last year I had the good fortune to link up with a small NGO in Panajachel, Guatemala - Mayan Families - and they were kind enough to let me help them install indoor air pollution (IAP) stoves in villages around Lake Atitlan. I had been hand building my own version of the Justa stove nearby, but have been interested in the ONIL (developed by Don O'Neal and made locally by HELPS International) - because it is a stationary masonry stove that is mass produced and does not require any mortar for construction... it installs in just a few hours! There are now tens of thousands of the in the field, but the web documentation of installation experience is slim (see here for an animation of just the construction aspects) so I thought that I would describe my experiences.

The 2 main components are cast from concrete in a well organized end efficient factory, and delivered to installers by the truckload, with all of the other parts besides the 11 cement blocks which are used as a base - the kit is beautifully simple to work with, a crew of 2-3 installers can construct a half dozen a day, and families can begin cooking on them before we have even driven off. The process starts with the leveling of the ground at the proposed site in the kitchen (often where the old stove - a 3 stone fire or similar crude cooking structure - had been), an important step if the plancha is to be level and the stove stable. These stoves are designed to meet the needs of the local cooks, who daily cook tortillas and who would like to use their stove with several pots at a time, problematic if the metal surface is tilted.. This leveling process can be the most time consuming of the steps, requiring the use of a level and preferably some river sand to get it right; it is easy to skimp on this, but don't do it! A base of unmortared cement blocks is quickly laid down, and then the bottom and top parts of the stove are ready to be put in place.

The combustion chamber is made from specially shaped tiles made from baldosa brick, a material which is on the soft side but it is very resistant to elevated temperatures, and the multi piece construction method also keeps thermal expansion from causing this important component from failing prematurely. They also do not require mortar, since they interlock, and they can be replaced by the user if something goes wrong in the future. The chamber is surrounded by insulating materials such as porous volcanic sand (pumice) or wood ash, so that only the top surface gets hot, while maintaining a very high internal (combustion chamber) temperature so that the smoke is completely burned and the combustion efficiency is high. The design is such that the hot gases flow only through a narrow space just below the plancha, so that the heat is not wasted raising the temperature of the body too much. The family is hopefully nearby, helping with the process, and learning about how their stove is constructed - and how/why it works so well - because they have to maintain it for years to come. The scrubbed plancha is now put in place, the stove is again checked for levelness, and the chimney is ready to be installed.

At this point in the process, you want to begin laying the "first fire", so that the cook of the house can be boiling water while the installers are still there to answer questions - it is very important that some instruction be given, since tending a fire in a stove like this is quite different from what they are used to. Smaller split wood is necessary because of the reduced fuel opening, more frequent adjustment of the fuel may be required, and we want to demonstrate that less fuel can be required to accomplish the same cooking tasks. Studies have shown that these kinds of improved stoves do not naturally result in reduced fuel consumption, because by directing the smoke out of the house the cook may no longer maintain the fire at a minimum size - wasting wood and polluting the outdoor environment unnecessarily (

- note that they found that stove users typically thought that they were saving fuel). If the team is well prepared with gifts of firestarter and dry split wood then the fire tending instruction process can occur concurrently with the final stages of installation so that the team can quickly move on to the next home, and it is extremely helpful to schedule follow up visits so that good behaviours can be reinforced and questions answered; applying copious amounts of encouragement is an important part of promoting cultural change.

A hole is drilled in the roof of the house, the chimney is fixed in place with silicone sealant so that rain does not get in, the workspace is cleaned up (the old stove is often removed, to provide an extra incentive to use the new and improved model), and final instructions are delivered for properly maintaining their new cooking appliance. Hopefully, the water on the stove has already come to a boil with a surprisingly small amount of fuel, and another family is happy to start cooking in a neater/cleaner kitchen with no smoke to reduce their quality of life!

But not all works as easily as we would hope - without proper education and best practices reinforcement their new stove may not be used as intended, or it may not please the family as much as we would like. Which brings me to the subject of what could we do better when installing stoves like the ONIL (besides bringing down the price, which can be hard with full featured stoves like these, with an abundant amount of metal parts), and what happens when we don't try hard enough:
  • There is no substitute for good stove construction and installation - most of the ONIL is nearly bombproof, but if it is not placed on a durable and level base then no one will be happy.  Problems can occur when installers are paid by the stove, since this provides incentives to move quickly to the next home - perhaps scrimping on some aspects of the installation and instruction.
  • Have the family build it with you, since this creates a sense of ownership and drills in what it takes to do at least the minimal amount of maintenance. Work side-by-side and discus every part and feature - we can't always avoid subsidies, but we can instill a a sense of pride and ownership that may be a decent substitute for paying full price
  • Definitely take the time to build that first fire and prepare even a simple dish (if only tea or tortillas) with the family, so that you get the chance to discuss fire tending and stove operation. Even better is if you can take the time to visit the household over the course of the first few days, to reinforce best practices (splitting of wood into small pieces, always using a pot lid, not overloading the stove, drying of wood overnight on the stove surface, always using the grate, covering the fuel entrance when not in use, removing the buildup of ash daily, etc.) and discourage bad.
  • Anticipate that maintenance will be required, and arrive at a plan for encouraging that it take place. Cleaning the chimney is the most alien of the new chores, because many cultures
    have no experience with this task - and if it becomes blocked then it may never get cleaned/replaced. Similarly, if the combustion chamber bricks break and there is not a supply of replacement parts nearby then it is likely that the whole interior of the stove will become the combustion chamber (so efficiency and overall performance will suffer).
  • Try to investigate and understand the sociocultural environment that the stove will exist in - gender issues, work division, different uses of the stove (meal types, impact on home heating, holiday needs, etc.) - and remember that over the course of the year different stoves and fuels may be traditionally used. 
The ONIL stove is a very satisfying stove to install - there is an instant gratification to it that delights both the crew and the family, and that is worth something.  It is so simple that it skilled workers are not essential, though having some one along who is
good at cooking with this stove is a huge plus - theoretical stove tending advice does little for the instruction process.  One challenge is that such quality stove costs extra so we must keep looking for ways to reduce the manufacturing and distribution costs of new stoves, so that those that need them most both value their combination of attributes and can afford them.  It is unfortunate that the financial incentives - the savings due to the need for less firewood - may not be clear enough to users, or because there are poor mechanisms for saving money in the developing world; as well, present bias can interfere with people's ability to sufficiently value a purchase with long term benefits.

Below are some examples of the improper installation or use of ONIL stoves - to prevent this from happening regular field visits are suggested, it must be frequently emphasized that modifications to the stove will result in poor performance (which may not be obvious to the cook, since unfortunately saving firewood is not always a high priority) both due to fires which are too large and excessive air carrying away valuable heat, and it can be necessary to repair stoves which have been hacked or are broken. The most common alteration is an enlargement of the fuel entrance, and removal of the combustion chamber and grate so that larger pieces of wood (or more sticks at one time) can be used - we shouldn't be surprised by this since cutting wood to the smaller sizes required for many improved stoves takes extra time and energy.  The only way to prevent this is to demonstrate the fuel savings possible when the stove is operated correctly, and since they don't come with instruction manuals you need that hands on approach... and lots of encouragement, since changing one's cooking practices can be an awkward process.

Hacked ONILONIL Stove RepairSanta Catarina Palopo repaired ONIL stove
Repairing a hacked stove in Santa Catarina Palopo - all stoves were modified in this fashion before installation.

Paulina with Francisco's stoveONIL with a Bad PlatformDSCF3931
Re-purposed ONIL planchas (where did the rest of the stove go?), and installation of a hacked stove on a horrible base.

Wednesday, April 6, 2011

Change Engineering to the Rescue

How do people and communities change their behavior? We can do all the inventing we want, but if we don’t anticipate how people receive new ideas then we are probably doomed to failure – as soon as we leave, the innovations we brought with us to a developing world community are out the door as well. Aid organizations and engineers working on problems have limited resources – both money and time are scarce, but the problems that need solving are innumerable so we don’t have the patience to work on too many things that don’t work (because we dropped the ball and forgot to anticipate how people might react to change in their environment). If we want more successes we have to design our implementations better, taking into account everything we can learn about what makes people tick.

For lack of a better term I call this thought process “change engineering” – designing/implementing new products and innovations very deliberately so that they stick when applied to a new community or market – perhaps requiring equal parts anthropology and social engineering, with the harder sciences mixed in to address the technology part (and some things we have to make up as we go along)? Too often our teams going to the field are made up of traditional engineers only – people trained to appreciate new products for the sake of newness only, forgetting that not everyone is like us – specifically they might value innovation differently than we do. Our (first world) culture is famous for innovation and I find this to be practically a defining characteristic of life in these modern times - but it’s different in more traditional cultures. Imagine our distant forefathers eeking out an existence on the savannah, do we really think that the serial risk taker was the one who got the most genes in the pool at the end of the day? As I travel I find that it is more likely that they are the one written off as a menace to the well being of the community – a crackpot with at the very least undesirable habits.

Perhaps we need to try and correlate risk aversiveness with Maslow’s Hierarchy of Needs – where he speculates that people strive to meet basic needs (like feeding their families) before they move on to tackle more complex ones (like saving the environment). The ability to tolerate risk is correlated with security – represented by higher levels on the pyramid - which is distributed differently around the world. What if people with little disposable income don’t approach risk the same way we do – in our case we will borrow to the hilt on credit cards for consumer electronics we don’t need then still take out a for-the-rest-of-our-life 30 year mortgage on a house, while in most countries borrowing is from families and spending beyond means is not taken to the extreme lengths that we see here at home. It is widely known that people save money differently around the world, with poorer people tending to save more, but what does that mean? The financial literature speculates that saving money is a virtuous activity, and theorizes that “risk averse consumers set resources aside as a precaution against possible adverse changes in income”; our culture meanwhile incorrectly assumes that our present level of income will always be there.

People may have savings that they seem unwilling to spend on things that we think will be valuable assets for them – foiling our plans – because purchasing such unfamiliar goods represents an unacceptable risk to them. We must consider the implications of this mentality when we want to introduce say an improved cooking stove (perhaps saving them time and money, and improving health) that competes with the status quo – often just a simple ground stove fueled with free biomass. The new thing is sometimes just too strange. If you add into the equation differences in the way people value their time – free time may not be such a luxury in much of the world so typical activities like firewood collecting are not necessarily judged as drudgery – we can find that even giving away free useful goods is problematic! Of course the key to engineering change better is more observing – until you have become an expert on your community’s problems and have lived life a little in their shoes. Collect some firewood, start a fire with wet wood, cook a meal over a traditional three stone fire… and definitely listen.

Wednesday, March 9, 2011

Micro-Gasification Masterpiece Publication Out

There is a new publication out on all aspects of micro-gasification stoves, a more general name for gasfiers such as TLUDs, which have seen tremendous improvements over the last few years. Christa Roth is the author, GTZ (now GIZ) has published it, and it is really a 96 page work of art! It covers many of the commercially available stoves, and a few less familiar ones, in great detail and with lots of relevant hyperlinks - and prototype stoves that have not yet reached production are discussed as well. Even some do it yourself stoves are touched on - these may be problematic for long term use, because the plain carbon steels in found materials (obtanium) don't last long enough, but they are very useful for development and educational purposes.

Sunday, February 15, 2009

ETHOS 2009 Stove Conference

This was my third ETHOS (Engineers in Technical and Humanitarian Opportunities of Service – a long name for people who often just call themselves “stovers”), and the Seattle suburbs are as cold as usual at this time of year. ~100 researchers came from around the world to compare notes on stove projects, stove designs, standards and testing procedures, health impacts, other associated appropriate technologies, and so on. More apparent this year was interest in carbon credit funding and biochar (terra preta) applications, and all year long there has been an increased emphasis on refugee camp stoves (and more testing of stoves in the field, versus in the laboratory) so this was more apparent at the conference. There was a raft of new stoves introduced this year, including the new BioLight thermoelectric-powered-fan one for camping and more, the likewise fan powered LuciaStove from WorldStove (shown with developer Nate Mulcahy), and the souped up Peko Pe natural draft gasifier presented by Paul Anderson (pictured with Crispin Pemberton-Pigott, wielding his ever present combustion analyzer). The dual venerable Dr. Larry Winiarski and Dean Still are also shown here with the upcoming finned pot atop StoveTec’s rocket stove - now 36,000 strong in the field just since last year. The trend toward stove models like all these, designed for mass manufacturing, continues, and this trend was recently discussed below. And yours truly demonstrated in light snow the new biomass gasifier (the big red one) from All Power Labs here in Berkeley. Look soon for Peter Scott’s new rocket stove design and application website. Past stove conference proceedings can be found here.

Saturday, August 2, 2008

Coming of the Corporate Biomass Stove - Mass Manufacturing to Save the Day?

Many of the improved cooking stoves designed for the developing world have traditionally been built by hand, on location, in relatively small numbers - a deployment of 10,000 stoves would be quite an achievement, and we have only seen this a limited number of times (each worthy of note and praise); only in China have we been capable of deploying the necessary millions (+125!) of stoves. While technically well thought out stove designs have been around since the 1980's. it has been hard to develop momentum so that truly large numbers can begin to make a dent in global problems such as environmental degradation caused by firewood collection, health problems due to indoor air pollution from smoky fires in the kitchen, and most recently the specter of global warming due to poorly combusted fuels. The obstacles to be overcome for this to happen are many, including the challenge of introducing improved stoves in thousands of different communities (all with unique cooking practices, fuels, and just different cultures), a lack of disposible income (and just as important - cash flow) in target communities to pay for even obviously beneficial stoves, some memories of bad implementation experiences in the past, and a resistance by funding agencies to make a commitment to solving hard problems with an appropriate approach.

The World Health Organization (WHO) is a very visible agency with clear opinions on what to do to improve the situations of the 3 billion people who cook with biomass fuels, and they have taken responsibility for reporting the "proportion of the population using solid fuels" as an indicator for reporting progress towards Millennium Development Goal 7 - to ensure environmental sustainability. Their brochure Fuel for Life is an introduction to their views on the problems and solutions. It seems that, in their opinion, using traditional biomass fuels is not consistent with.... can I believe this?... a decent quality of life - essentially giving up on improved biomass fuels and stoves as viable alternatives to liquid and gas fuels (and electricity) as "approved fuels" for sustainable, healthy, and environmentally appropriate progress. My complaint is that this is despite the obvious gains made in the last few years to improve efficiency and reduce emissions!

What of the alternative - continuing to learn to use our ample biomass resources responsibly and appropriately? The vast majority of fuel choices originate as solid biomass, and going to the effort of transforming them to more modern fuels can't help but result in energy and carbon accounting distortions in their conversion/transportation steps. It doesn't help that I consider myself to be a bottom up development advocate, believing in putting in more field time to understand what is most locally appropriate. Proclamations like the Millennium Development Goals suffer from problems like paying little attention to responsibility and accountability... who will personally take charge of this ambitious fuel transition effort for billions of people, and then perhaps suffer when it proves impossible to realize? Setting manageable goals is the first step toward progress.

Indeed the present situation would seem to be overwhelmingly discouraging if it were not for new developments, of interest here are the ones from the private sector, that are cropping up all over. For the last year or three there has been a huge amount of activity in what I call "corporate stoving" - it is not as if corporations of one kind or another have not always had cooking wares for sale (certainly in the developed world!), but they have not always been this active in developing countries - the market certainly is huge, but the margins are uncertain and the customers non-traditional. I could speculate on their ulterior motives, but suffice to say they are welcome players - the more technology rich stoves they are testing have the potential to reduce fuel consumption by 50% and drop emissions significantly, and result in deployments of tens of millions of units each.

My first experience with one of these was at Aprovecho's 2006 Stove Camp where a bare bones Philips Electronics model was under testing - what a beautiful fire the swirling air made, and it just ate up the waste wood with never a trace of smoke. Even in this early form (without glossy exterior and internal battery) it was a marvel of efficiency, the culmination of 4.5 billion years of learning how to make biomass fires on planet Earth. It provides the right amount of air to the right places at the right times - I don't know if you can combust fuel much more efficiently (so now we need more work on transferring the heat more effectively to the pot and food, the other half of the technical problem). The Philips business model is admirable - fully support your customers' new "cooking appliances", backing them with spare parts, maintenance facilities, and a warranty. Since 2006 Philips engineers have presented regular progress reports, and testing goes on in India - customer acceptance is of course crucial, and the thermoelectricity powered fan (with a NiMH AA battery for starting) is a critical part of the reliability requiring extensive field testing. But the real challenge is developing mechanisms to teaching people the advantages of a radical new stove and way of cooking, necessitating lessons illustrating possible initial downsides as well (there always appear to be some disadvantages compared to their present stove - no one stove, or fuel, suits every situation) - the best technology counts for naught without a dynamite cooking culture change plan.

British Petroleum's Oorja stove is part of BP's Emerging Consumer Market (ECM) strategy to provide energy solutions to the billions of people cooking with biomass. The most extensive discussion of it is in a June 2007 article in The Hindu newspaper here, and it describes a computer fan powered batch loading stove running on compressed pellets (presumably like small U.S. heating stove pellets) costing ~$USD 15 - hundreds of thousands of stoves were in operation at that time. Village based businesswomen sell the stoves and the pellets made from agricultural waste - a new infrastructure for pellets (or other kinds of briquettes) will be needed to compete with existing firewood and charcoal ones if people are to make the transition to stove designed to use these more environmentally sustainable and benign alternatives. It resembles a top loading updraft type gasifier, with credit given to the Indian Institute of Science, and they have ambitious goal of 20 million sold by 2020; their promotional video of it is here, and Yale has an excellent overview here.

Perhaps I heard about the Bosch-Siemens plant oil stove next - though I have yet to see one. Again, the influence of corporate R&D expertise is obvious in its sophisticated design and attention to detail. Cooking stove oil appropriate biomass typically is purpose raised (hopefully not for its food value), and there are a wide variety of choices - jatropha is often mentioned these days as an example and small oil presses can be built locally to provide jobs and economic security right where the stove benefits are also located. We can always hope that there is room for regional variation and distributed manufacturing - they have a stated commitment to locally produced oils - let's pray that plant oils from locally appropriate crops will always be competitive with upcoming bioengineered and watered/fertilized mono crops. In volume they expect that the stove price will be $USD 20 and this article reports on the deployment of a first 100 stoves in the Congo earlier this year - like all of these stoves the Protos is in the development and testing phase, so we can expect to see changes and reports from far flung places around the globe (using its partners, this one is planned for field trials in a number of countries such as Indonesia, Philipines, India, and other parts of Africa) - and see the price drop as more efficient manufacturing is realized.

Aprovecho and the Shell Foundation have worked together for years developing stoves that have fewer emissions, and on refining the tests to measure them. The latest from the Shell Foundation is their collaboration with Envirofit, aiming to deliver tens of millions of Rocket stoves to the world before you know it. I have seen the simplest model and there are great design pictures out there for coming models) - we should expect a metal combustion chamber backed with an insulating ceramic, with various attractive shells - a glimpse of their future model in testing as reported here in the NYT. Their effort is evolving quickly so expect to soon find all kinds of additional information out there.
One of the things we expect to see from the biggest players is marketing of these new stoves as if they are any other new consumer product - focus groups, advertising, brand management, as well as hopefully a network of distributors for repair and spare parts (and perhaps even branded fuel). And it is expected that turning a profit will be part of their business models, but for now only they how - unfortunately subsidies have always been a part of improved cooking stove programs, since people rarely have the cash on hand (or cash flow - banks are mostly a developed world phenomena) to buy a stove even if the payback due to fuel savings is clear. Manufacturing economies of scale and consistent quality - plus new methods of outreach, financing, support, and attention to customer feedback - should favor capitalism finally, and if not then providing incentives is nothing new and can be considered. Later.

The Approvecho Research Center is anything but a global corporation (their emphasis has traditionally been on R&D), but they have just entered the stoving arena as a big player by rolling out their independent StoveTec line of products, manufactured in volume in China. They practically invented stoves made with a metal shell and fluffy ceramic Rocket elbow... and now they have a price that is just plain hard to believe - on the dock in Ningbo these can be $USD 6 in volume, and you can buy spare parts as well. A side fuel feed entrance (instead of the top loading versions that we are seeing from everyone initially) certainly is appropriate for a fuel flexible stove, and the folks at Aprovecho can be expected to come out with it first.

A "fan assisted" stove marketed for camping (a developed world activity only) is the Woodgas Campstove, an evolution of the one first proposed by long time biomass advocate Dr. Tom Reed - over the last 3 years this one has logically progressed from a rough design to the present polished stainless steel versions (two sizes) that should also appeal to the developing world. They are presently made in India, and we can only encourage then to experiment with local distribution there. Note that the Philips and BP ones also have a fan (you will also see the term "gasifier" used often), a term meaning that they usually require batteries or a cord to power them - at first this may not seem suitable for the developing world, so let's consider this further. In most cases these are destined for growing metropolitan suburbs where charcoal fuel tends to dominate, costing families as much as 1/3 of their income; these people tend to be familiar with technologies like cell phones so the arrival of a new battery powered appliance is not necessarily a complication. Given that these stoves can require only one watt of fan power to produce ~3000 watts of cooking energy from previously waste materials, there are some huge incentives to switch back to raw biomass - with a net benefit not just in fuel and cost savings, but a lighter impact the atmosphere.

There are a number of other stoves worth mentioning here which aren't backed by a multinational that may have trading carbon credits in mind too (efficient stoves are carbon neutral), all with the potential to scale their production up - if they have not already done so by the time you read this. These are already made professionally and when there is the demand they are designed to be made in volume with modern quality control methods, shipped around the world, and supported in the field. Examples pictured here are the Vesto stove from New Dawn Engineering (South Africa), 25,000 German made Save80 stoves are deployed in refugee camps (shown here being used in Nigeria), and the very promising Turbo Rice Husk Stove from the Philippines burns rice husks with absolutely beautiful flame characteristics. Stoves with chimneys, to address specifically indoor air pollution concerns, can be harder to mass produce because of their size, but in Central America two standouts producing more than their share are the Ashden Award winning factory-made concrete ONIL stove (Guatemala primarily) and the metal ADHESA/Trees Water People (Honduras).

Sunday, February 3, 2008

ETHOS 2008 Conference

Again ETHOS (Engineers in Technical and Humanitarian Opportunities of Service - motto: "Changing the household at a time") met in Kirkland, WA for its annual conference last weekend. This tends to be a meeting of mostly "stovers" (designing and advocating improved cooking stoves for developing countries) but it is slowly adding other topics that address broader global problems. It is a manageable enough size (~100 people) so that most people know each other, are usually conference returnees, and they form a comfortable "stoving community". For the first time there were 3 simultaneous sessions going on in different rooms - a sign of more talks than before (and more time allocated for each), but a difficult situation for those of us who want to see every one.

This year saw an increase in efforts to mass produce improved stoves in factories, to get more out in the field, faster - talks were presented by Philips (a beautiful fan stove now being test marketed in India), Aprovecho (the cheapest stoves and parts imaginable - newly available and looking for their first mass field trial), and Envirofit (a new and very ambitious program, with vision and lots of conceptual stove designs). For stoves manufactured outside of the countries where they will be distributed ("locally made" has long been a tradition, because of transportation costs and funding issues, and the lack of commercial interest in this market) some concern has been expressed - should we keep shifting carbon responsibilities around the globe? And some stove types may always be local because of the low volumes required - these places needs unique stoves, to meet very local needs. The ONIL stove in Central America should qualify as well as a volume producer, with thousands of new IAP stoves manufactured every month, and Trees, Water, People will be opening a new stove factory in Honduras soon, with AHDESA. When should we consider emulating proven, cost effective (and manufacturing/implementation optimized) programs in other locations/countries - perhaps 100 km apart so that we are local and have less transportation problems? But for similar sociocultural and cooking practice circumstances, why should we keep re-inventing the wheel? Certainly, at present things appear to be accelerating and building momentum as new manufacturing/distributing models are being tried.

In the background was always lurking modern publicized stove global goals, like the "billion stoves" challenge, and the U.N.'s "Millennium Project" (the stoves/IAP aspects, from the WHO perspective, are here) - though of course stover researchers and implementers work with these in mind every day. There is also a new appreciation of the role of cultural research/participation - someone commented that "the solution" may only be 2% engineering, less than my constantly decreasing estimate of 10%.

There were also talks on the results of finned pot experiments (the potential fuel savings with these is very impressive), new TLUD stoves and activities in India particularly, new tools available for quantifying emissions (from Aprovecho and the Berkeley Air Monitoring Group), health effects of traditional indoor cooking practices, stove efficiency testing and analyses of the validity of present common testing procedures (such as the WBT, KPT, and CCT), and a number on "integrated cooking" - where improved cooking stoves are combined with solar cooking and retained heat cookers, taking advantage of the benefits of each one. I can't list all the talks and the countries represented here (my favorite image was of a llama dung burning stove in Bolivia, since I used to raise them and know its easy collecting characteristics, courtesy of CEDESOL), but ETHOS will soon publish the full proceedings here, where you can also find the proceedings of the last few meetings.

One of the favorite parts of the meeting is always the burning stove event at the very end, where people bring their newest stoves to show off and get comments on them - its amazing how people drag some of the bigger ones there from all over the world!