Biomass Energy Foundation

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 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

Palm Fronds as Fuel in a TLUD (Top Lit Updraft)
Micheal Trevor, Marshall Islands, December 7, 2008

Loaded Chopped Fronds

Envirofit and BP Stoves
Tom Reed, www.woodgas.com, August 29, 2008
Envirofit and BP Stoves

On Fri, Aug 29, 2008 at 6:38 AM, Thomas Reed tombreed@comcast.net wrote:
Dear Stovers:

I am attaching [the image above]that may be of interest to the stovers.

Here is an unsolicited commentary on our new XL WoodGas Stove, available at

http://www.woodgas.com/bookstore.htm
Woodgas stove
along with our gasification books.

We have recently learned that BP is manufacturing a VERY similar stove
and selling them (only in India) in their equivalent of Walmart. I hear
they have already sold 100,000. Sounds like we are well on the way to
getting a "Billion Improved Stoves" out to the developing world.

If you cover the combustion air holes with aluminum flashing or sheet
metal screws the stove also makes a good gasifier.

Onward,

TOM REED