Dean,
Thanks for asking. We want clarity about such important innovations.
Certainly Wendelbo was first to invent the concentrator disk, in about 1995 in Uganda. It is the key (or one very major key) to success with natural draft (ND) TLUD stoves.
Reed never did it. After his work with the Reed-Larson natural draft “inverted down draft” (not named TLUD until 2005) in 1995-96, he shifted his attention to forced air (FA) micro-gasifiers (which I saw in 2001 and that got me hooked,
but I wanted it to be with natural draft (ND)).
In 2004 and early 2005, in discussions with Reed, I learned that it would be good to “force” the mixing of the secondary air and the rising pyrolytic gases, which does not happen sufficiently at the outer edge of an open-top fuel canister.
So I put on a lid with a hole in the middle while making a stove in Bolivia. It worked. I brought that stove to the summer 2005 Stove Camp at Aprovecho where it won the (to me, much coveted) first Cat Pee Award, and earned the name “Champion”.
About 3 years later Paal Wendelbo began participating in the Stove List Serv. After careful questioning, I determined that he created the essential “concentrator disk / lid” about ten years before I did.
Reed and Wendelbo are the two, independent fathers of these pyrolytic gasifiers small enough to be cookstoves. I claim to be the “adopted father” who had the privilege to name and nurture this creation first called “Top-Lit UpDraft” in
2004 and then by the acronym “TLUD” in 2005.
Most of this story but in different words is in the document “Origins and History ……..” available at
www.drtlud.com (check the “Quick Picks”).
Please note that in 2015 ESMAP recognized TLUD gasifier stoves as being the only solid biomass cookstoves classified as “Advance, Modern Clean Cookstoves”, being distinct from the Traditional and the Improved Cookstoves (ICS). Now in
2021 at the CCA meeting (virtual), both ESMAP and CCA continue with that recognition. TLUDs (especially those with fans and pellet fuel) are in the advanced league with LPG, Electricity, solar, natural gas, biogas and alcohol.
Also note that of any cookstoves of any type or fuel, TLUD micro-gasifiers are the ONLY cookstoves that are CARBON NEGATIVE. The produce biochar naturally and easily.
But the CCA still prefers LPG, a cookstove/fuel combination that requires the stove users to purchase industrially processed fuel.
Paul
Doc / Dr TLUD / Paul S. Anderson, PhD — Website:
www.drtlud.com
Email: psanders@ilstu.edu Skype: paultlud
Phone: Office: 309-452-7072 Mobile & WhatsApp: 309-531-4434
Exec. Dir. of Juntos Energy Solutions NFP Go to:
www.JuntosNFP.org
Inventor of RoCC kilns and author of Biochar white paper : See
www.woodgas.energy/resources
Author of “A Capitalist Carol” (free digital copies at
www.capitalism21.org)
with pages 88 – 94 about solving the world crisis for clean cookstoves.
From: Dean Still <deankstill@gmail.com>
Sent: Sunday, December 5, 2021 12:42 PM
To: Anderson, Paul <psanders@ilstu.edu>
Cc: Kirk H. <gkharris316@comcast.net>; Ronal W. Larson <rongretlarson@comcast.net>; James Jetter (jetter.jim@epa.gov) <jetter.jim@epa.gov>
Subject: Re: Recent TLUD work
[This message came from an external source. If suspicious, report to
abuse@ilstu.edu]
Who invented the concentrator ring? Wendelbo and Reed?
On Sun, Dec 5, 2021 at 10:34 AM Anderson, Paul <psanders@ilstu.edu> wrote:
Glad to see further work on TLUD technology.
I will not be attending the “ETHOS at ARC” week. I hope those who do attend have a wonderful time.
Paul
Doc / Dr TLUD / Paul S. Anderson, PhD — Website:
www.drtlud.comEmail:
psanders@ilstu.edu Skype: paultludPhone: Office: 309-452-7072 Mobile & WhatsApp: 309-531-4434
Exec. Dir. of Juntos Energy Solutions NFP Go to:
www.JuntosNFP.orgInventor of RoCC kilns and author of Biochar white paper : See
www.woodgas.energy/resourcesAuthor of “A Capitalist Carol” (free digital copies at
www.capitalism21.org)with pages 88 – 94 about solving the world crisis for clean cookstoves.
From: Dean Still <deankstill@gmail.com>
Sent: Sunday, December 5, 2021 12:26 PM
To: Kirk H. <gkharris316@comcast.net>; Anderson, Paul <psanders@ilstu.edu>; Ronal W. Larson <rongretlarson@comcast.net>;
James Jetter (jetter.jim@epa.gov) <jetter.jim@epa.gov>Subject: Recent TLUD work
[This message came from an external source. If suspicious, report to
abuse@ilstu.edu]
Hi Kirk, Paul, Ron, and Jim:
Hope you can come to the ETHOS at ARC week! Looks like Anton will not be here because of travel restrictions from South Africa to the USA. Just finishing another dive into TLUDs:
ARC worked on the Peko Pe (invented by Paal Wendelbo) many years ago with an organization promoting the stove and made changes as each iteration was tested under the emission hood.
During November-December 2021 we took the work up again and did the following:1.)
Used secondary air holes under the concentrator ring to hopefully create better
mixing. The idea is that the jets of air start the mixing process.2.)
The
primary air entering the chamber is controlled by an adjustable sleeve. (Thanks to Kirk Harris who introduced ARC to controlling primary air in a TLUD.) 1.) When the rate of reactions is too fast and the burning wood makes smoke (the combustion zone
above the fuel chamber cannot combust all of the woodgas and some escapes as gases and smoke) the primary air is reduced to slow the rate of reactions. 2.) When the transition from burning wood to burning charcoal is complete, the primary air is reduced to
more efficiently burn the made charcoal.3.)
The stove is intended for urban use. Therefore, it was
changed from a TLUD into a T-CHAR. When the wood is consumed the top half of the stove is removed and the pot is relocated onto the bottom half to more efficiently cook with the made charcoal. (Thanks to Dr. Paul Anderson and Christa Roth for the T-CHAR
concept.)4.)
Use a pot with a skirt and a Winiarski stove top with 6mm high pot supports.
Optimizing the heat transfer efficiency is our first step in improving a stove often without increasing the cost. Needing less wood to boil water and cook food is helpful in many ways including emitting less harmful pollution. (Thanks to Dr. Baldwin and Dr.
Winiarski.)5.)
Adjust the
flame until it barely touches the bottom of the pot. The 100C pot bottom condenses escaping particulate matter and can result in deposits of creosote and smoke. (Thanks to Kirk Smith.)6.)
A static mixer positioned between the top of the fuel chamber and the pot
assists mixing and reduces flame height. The mixer also seems to radiate heat down to the fuel magazine and can increase firepower. Various shapes have been tried. A stationary propeller designed for 3mph flow was the most successful, in this case. (Thanks
to Kirk Harris.)All Best,
Dean
Dean Still
Research Director
Aprovecho Research Center
Advanced Studies in Appropriate Technology
PO Box 1175
76132 Blue Mountain School Road
Cottage Grove, OR 97424
(541) 767-0287
—
Dean Still
Research Director
Aprovecho Research Center
Advanced Studies in Appropriate Technology
PO Box 1175
76132 Blue Mountain School Road
Cottage Grove, OR 97424
(541) 767-0287