Using a TLUD for Pasteurization at the Paramount Dairy in Uganda
John and Charles Anglin, Uganda, October 19, 2009
Pasteurization of 450Lts Milk Complete after 1.5hrs
Pasteurization of 450Lts Milk Complete after 1.5hrs

John and Charles Anglin have built an institutional / industrial size TLUD for pasteurization at their Paramount Dairy in Uganda. Their 2-page report with 4 photos describes and shows the TLUD and the 450 liter milk-vat. The fuel is papyrus reeds. This report is about a "work-in-progress," and they have given permission to post it to the Stoves Website. The Anglin's can be reached via the Stoves Listserv.

Courtesy of Paul Anderson

Paul Anderson, 2009 SeaChar Stoves Workshop

The efforts at SeaChar (Seattle Biochar Initiative) produced a 5-gallon (22-liter) TLUD.

"On Saturday, August 1, Seachar hosted Dr. Paul Anderson (Dr. TLUD) for an all-day workshop in the construction of Top-Lit Up Draft (TLUD) cookstoves. The stoves can quickly be constructed from commonly available materials, and produce charcoal while providing heat for cooking (or other uses). Paul’s TLUD stoves have been tested and shown to produce very low emissions of CO and particulates. The stoves can provide benefits wherever people rely on biomass for cooking. TLUD stoves use a wide variety of small pieces of biomass for fuel. The clean burn greatly improves indoor air quality compared with open burning and many other types of stoves. In addition, the charcoal can be used as biochar to improve soil fertility, sequester carbon, and potentially provide a source of income through carbon credits."

For More See:

The focus was for making biochar, but this size of TLUD will be highly appropriate of institutional-size cookstoves in the developing countries.

File attachments: 

Paul Anderson, March, 2009 How many of each major type of cookstoves exist in the developing societies(functioning in 2009)? The attached "draft" Matrix gives you my guesses. Perhaps YOU have additional input. Maybe we should change the Matrix. More columns, more lines. Or do you agree with what content? What I am attempting is to get us all reasonably "on the same page", literally on the same single page. Please look carefully at the two Notes at the bottom. In the general rank ordering, any stove type (or specific stoves within a type) might be shifted one or two columns to the left or right. But the question is, are the notes and orderings reasonably correct? There is no right or wrong, best or worst. By sheer numbers of units, the 3-stove fire is "best." It literally is "the competition to beat" for all of the other stoves. The file is an active MS Word document ( .doc), so you can change it as you please, but please indicate that you have altered it. (I desire neither the glory nor the blame for what you contribute.) It is a very small file and might be distributed with this message.

Paul Anderson, March, 2009

I. Proposal:
“Air-controlled” biomass cookstoves should be seriously examined as viable replacements for charcoal cookstoves in urban and peri-urban communities in developing societies.

II. Situation, Problem and Opportunity:
Throughout the urban areas of developing societies, charcoal cookstoves have an important role in
residential cooking (including other small-scale cooking in restaurants and institutions). The acceptable energy sources for urban cooking are charcoal, LPG, kerosene, alcohol, and electricity. (Solar cooking is omitted because of housing densities and shadows.) All of them require significant “conversion” from their natural sources, and are deemed to be sufficiently clean energy, meaning a “lack of bothersome smoke” or very low emissions of particulate matter (PM).
Charcoal competes well against those other high-order heat sources because it is easily and relatively inexpensively made from wood and other dry biomass by unskilled labor. But charcoal has two major drawbacks: A) very high levels of carbon monoxide (CO) emission; and B) the destruction of local vegetation from which the charcoal is made. Therefore, it is important to examine viable alternatives such as modern cookstoves that efficiently combust raw dry biomass such as wood which yields CO and PM emissions (“smoke”) even lower than those of charcoal stoves. If these new stoves are successful, task-appropriate, and sustainable for urban cooking, they will also significantly reduce the problems of deforestation and greenhouse gases while providing urban residents with economical and convenient fuel alternatives.

Construction Plans for the “Champion-2008” TLUD Gasifier Cookstove (including operational instructions) Paul Anderson, March 1, 2009


The document attached contains detailed instructions for the construction of Anderson’s "Champion-2008" top-lit updraft (TLUD) gasifier that can be used in many different cookstove structures. On 18 pages with 39 Figures, the “Champ” is described in three versions (Hobbyist, Refugee and Artisan) with the same dimensions but using different materials and metal-working skills.

Notes from the ETHOS Conference of 2009,
by Paul S. Anderson, 4 February 2009

I enjoyed (and benefited from) the 2009 ETHOS Conference more than in most previous years. ETHOS is growing and evolving, and so are our stoves.

This year we seemed to have had more discussions of issues than in the past. There were topical “panels” of usually three or four qualified people. The topics of these plenary sessions were: Carbon Credits; Stove Testing Issues (not results of specific stoves); Safety; and Stove Standards. Those sessions still tended to be presentations, but there was somewhat more interaction and some effort to get to the underlying difficulties that need more discussion. Attendees still need to read-between-the-lines and/or have some more private discussions to see some of the differences of position.

The session Crispin and I led about controversial issues that need to be discussed was only moderately successful (in my opinion) because we spent our time identifying the issues and did not have time for discussions of those issues. Next year, we hope to have some of those topics PRE-identified and to have discussion time about those issues. I have volunteered to work on that, and Mark B. has accepted my offer. (More about this in some future messages.)

There were still about 30 somewhat standard (academic style) presentations, usually with PowerPoint slides. But they were in three concurrent sessions with 30 minutes (too much in my opinion) allocated to each presenter (who usually did make sure to fill all of the minutes, often with background info that could have been omitted, in my opinion). So each attendee could only hear about 10 of them. I will comment on four of the nine that I was able to attend. There were certainly other excellent presentations, but I am not trying to summarize the entire conference.

1. Alan Berick did a masterful job of calling attention to simmering by the use of only charcoal, available from the fire that was used to bring the pot to boil. There were questions about the heat retained in a ceramic stove body, etc., and certainly he will do more work on this. But really he called attention to the need to have “different” heat sources for boiling and simmering. This is akin to the advocacy of retained heat cookers (RHC or “hayboxes”) for integrated cooking. We should all think more about having two or more modes or devices for different cooking (as in bringing-to-boiling vs. simmering vs. tea-for-two in the morning).

2. Jonathan Cedar and Alex Drummond discussed (and later showed) their “BioLight” cookstove that includes an attractive device attached to the side of the stove to use the heat of the fire to create the electricity (via a TEG = thermoelectric generator) to drive the blower to make the fire burn well. The theory and practice have been known for a long time, but they impressively accomplished it in their attractive prototype, a variation of a Reed-style Woodgas Campstove. Neither the stove body nor the TEG power units are available for purchase, but they should be encouraged to continue their work. [Side note: The TEG in the bottom of the innovative Philips cookstove (seen in previous years) has been removed and that stove is moving to the marketplace with battery or plug-in for the required electric power.]

3. I liked my own presentation about the low emissions of TLUD gasifiers, especially if the charcoal is NOT burned in the TLUD. This favorably relates both to Alan Berick’s findings (above) and to the carbon credit and biochar sequestration topics. (Enough said. My paper is at the Stoves Internet site: I think that in future years we should have many papers placed there in advance of the conference.)

4. Nathaniel “Nat” Mulcahy attended ETHOS for the first time and (in my opinion) presented the most dramatic stove innovation I have seen since the day I met Tom Reed and his TLUD prototype. Nat presented about the Lucia Stove (and some info about the larger WorldStove). True science and engineering in action. His website is underdeveloped, but he has 13 YouTube items that will partially bring you up to speed. Visit: I will be writing more in another message about his “coaxial gasification” (vs. stratified gasification in TLUDs and most other small gasifiers). I spent some extra time with Nat and can say that he has deep understanding of the issues, and he has solutions already in place.

The “Lighting of the Stoves” was Sunday afternoon, with a light snowfall!! Five stoves were fired up.

1. The Rocket stove produced in China. Reliable, economical, and this one had a very nice pot-skirt that attached to the pot and let the emissions/draft out through (20 mm??) holes near the top of the skirt. Many people (including me) purchased one of those stoves (and would like to get the skirt). Contact Aprovecho to get your stove (under US$30, plus shipping).

2. The “PP-Plus” natural draft TLUD from Servals in Chennai, India. It uses the natural draft techniques combined by Paul Anderson and Paal Wendelbo. I will be posting within a few days a document on how to make a PP-Plus gasifier. (Wendelbo’s extremely interesting life as a TLUD pioneer was highlighted at the Friday night slide-show and is at the Stoves Website: ).

3. The GEK downdraft gasifier. This is not a cookstove. It is a gasifier intended as a start-up kit for aspiring gasifier enthusiasts, including cleaning and cooling of the gases. This is for sale as a kit or as a set of plans for construction. About forty units are around the world.

4. The Lucia Stove by Nat Mulcahy. Mentioned previously. The live-fire demo was impressive. The turbulence of the gases/flame and the air control provided a very clean combustion, measured by Crispin and his furnace-emissions analyzer.

5. The BioLight by Drummond and Cedar. Discussed previously. It performed very well, and was measured by Crispin to have very clean combustion slightly better than the other four stoves shown this year.

As someone mentioned, in previous years usually only one gasifier was among the stoves ignited. But this year four of the five were gasifiers, each distinctly different from the others.

The “Crispin Awards” were inaugurated this year. Crispin gave out three little bottles of “Gold Medal” Canadian pure maple syrup to stoves 3, 4, and 5 in the above list. The criteria were the emissions readings from his furnace emissions analysis equipment. The three winners did share one thing in common. All three were with force air, and even used true blowers, not just small fans.

In summary, it was a beneficial conference. Another report on the meeting has been posted by Kelpie Wilson, with insights especially for the issues of biochar:

CO and PM Emissions from TLUD Cookstoves Presentation to 2009 ETHOS Conference, Kirkland, WA 23-25 January 2009 Paul Anderson, Biomass Energy Foundation, January 22, 2009

CO and PM in TLUDCO and PM in TLUD

Introduction Since 2005, high quality quantitative data on emissions from cookstoves have been accumulating. For data to be properly comparative, both a standardized cooking task and reliable emissions measurements are required. The principal test continues to be the standard five-liter Water Boiling Test (WBT), about which much has been written and debated. Equipment for reliable emissions measurements has been gathered, installed, tested, and accepted for operation at the Aprovecho Research Center (ARC) in Cottage Grove, Oregon, USA. No known equivalent site exists anywhere else in the world. Sincere thanks are given to the Shell Foundation, other financial donors, the ARC organization, and the numerous scientists who assisted in the establishment and operation of those emissions hoods. While the ARC facilitated the gathering of data presented here, the author is responsible for interpretations and any errors or omissions. Dozens of different stoves have been tested to various degrees with the ARC equipment and methodologies. Hundreds of separate test results have been collected. The two measured emissions are carbon monoxide (CO) and particulate matter (PM). This report is focused upon those emissions from four categories of cookstoves: 1. The traditional “three-stone fire,” which provides baseline data. 2. “Simple improved cookstoves” that utilize basic combustion that is confined in various stove structures made of ceramics, mud, or metal. 3. “Rocket stoves” that utilize clear principles and designs that provide significant control over the amount of wood in the area of combustion, with some restriction on the flow of air to the combustion area. 4. “TLUD (top-lit updraft) gasifier stoves” that essentially separate in time and location three processes of biomass burning (pyrolysis, char-gasification, and combustion). They also emphasize separate control of primary and secondary air supplies. Robert Flanagan, a TLUD stove developer in China, has coined the term “third-generation cookstoves” for these stoves that have the capability to easily create and save charcoal for use as a “biochar” additive to improve soil fertility (as in “terra preta”) and to remove permanently carbon from the atmosphere. See attached presentation

Paal Wendelbo and His “Peko Pe” Top-Lit UpDraft (TLUD) Gasifier Cookstoves
Paul Anderson, January 19, 2009

Paal WendlboPaal Wendlbo

This report is in three parts: pioneer experiences; selection of photographs; and technical specifications of the PP stove. The report is based on e-mail interviews and materials provided by Paal Wendelbo in July 2008 and December to Paul S. Anderson, who has added interpretive content. Mr. Wendelbo has approved the basic content about himself, but Dr. Anderson is responsible for any errors, omissions, and editing.


Dean Still, August 9, 2008

TLUD Gasifier in Ashden Award for Enterprise
Paul Anderson September 21, 2007
Shenzhou DaxuShenzhou Daxu


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