2010 ETHOS Stove Conference

By Kelpie Wilson

You may have read about the “stovers” in the New Yorker last December in Burkhard Bilger’s article, “Hearth Surgery”. This dedicated group, intent on providing clean cook stoves to the world, met at their annual conference January 29 - 30 in Kirkland, Washington. The conference is organized by the ETHOS group and Dr. Mark Bryden at Iowa State University. This was my second year in attendance and the stovers are slightly less quirky but even more wonderful than Bilger's portrayal of them.

It would seem to have been a very successful year for the stove community. Two companies, Envirofit and StoveTec, are now manufacturing and distributing hundreds of thousands of the clean-burning rocket stoves. Mass production of a desirable and affordable stove for developing countries is a major milestone. However, the mood at the conference was not of self congratulation but of deeper probing into the problem of access to clean stoves. After all, the need for stoves is huge, 2 billion people are still cooking over open wood fires. Even a million stoves is just a drop in the bucket.

There was much discussion of the history of stove projects: how they have largely failed to meet objectives and how the objectives have multiplied over time as new requirements are added to the original goal of reducing fuelwood use. Stoves are now required (at a minimum) to slow deforestation, provide cleaner indoor air, and reduce greenhouse gasses. New objectives for cookstoves include generating electricity with Thermo Electric Generators (TEGs are like a solar photovoltaic chip that runs on heat) and producing biochar for use in soil.

Another new development in the stoves world is more serious consideration of carbon financing. There are many ideas for tracking, monitoring, and aggregating stoves programs so they can receive carbon funding, ranging from wireless data loggers imbedded in stoves (they create a temperature record that can be downloaded by an aid worker walking through a village) to various cell phone schemes. In addition to money, many people were hopeful that carbon financing would add rigor to the stoves effort by requiring follow up and monitoring and getting out of the “drive-by development” syndrome that has resulted in so many failed stove programs.

Black Carbon

With climate change front and center, there was much interest in a presentation by Dr. Tami Bond of the University of Illinois on Black Carbon (soot) emissions. Black Carbon has a strong radiative forcing effect in the upper atmosphere and soot deposits on glaciers darken their color and reduce reflectivity. Dr. Bond is in the midst of a project of comparing stoves and their black carbon (BC) emissions. Cleaner cook stoves have reduced CO (carbon monoxide) and organic carbon compound particulates, but have not managed to do much about BC, except for “stoves that control secondary air”. This means that the rocket stoves that most stove projects now use are not reducing BC emissions significantly.

One way a rocket stove can reduce emissions is to add a fan to provide secondary air. StoveTec is working with the stove designers from Biolite (who make a gasifier camping stove with a TEG powered fan) to put a TEG powered fan on a rocket stove. In contrast, it is possible for a well-designed Top Lit Up Draft (TLUD) gasifier stove to reduce BC even without a fan (and TLUD stoves can also produce biochar).

TLUD Gasifier Stoves

Dr. Paul Anderson, a.k.a., “Dr. TLUD”, made the pitch for TLUDs and biochar. He brought a complete lineup of TLUDs including one that is  manufactured in India. TLUD designers Art Donnelly, Christa Roth, and Hugh McLaughlin all had stoves on display. At the TLUD session participants compared rocket stoves to the TLUD and made a list of TLUD features: 

• Makes biochar
• Starts fast, burns a long time on one load of fuel
• Fuel flexible – uses small size waste that cannot be burned in other stoves
• Cleaner than traditional stoves (lower BC, Organic Carbon, and CO)
• Variety of scales and applications from cooking to metal forging
• Lightweight and modular, can use multiple units to control heat output
• Easy and cheap to build from tin cans or sheet steel
• Even for a household that has a rocket stove, a TLUD is a nice addition for fuel flexibility and for quick cooking jobs like boiling water for tea

Despite the advantages of the TLUD there are currently no major stove programs using TLUDs. BP and Phillips both have modest TLUD pilot programs in India and Nathaniel Mulcahy, designer of the World Stove pyrolytic gasifier (similar to a TLUD), is currently working in Haiti promoting institutional and household size stoves and gearing up to build 100 units per day.

Hopefully, the diverse display of TLUD technology at the 2010 ETHOS Stoves Conference will spark new TLUD developments in the coming year. With this bunch of stovers, a lot can happen in a year.