[Stoves] Stove testing methods

[Kevin Chisholm]

Dear Paul
----- Original Message ----- 
From: "Paul S. Anderson" <psanders at ilstu.edu>
To: "Kevin Chisholm" <kchisholm at ca.inter.net>
Cc: <frank at compostlab.com>; <stoves at listserv.repp.org>
Sent: Saturday, September 23, 2006 1:16 PM
Subject: Re: [Stoves] Stove testing methods


>
> Quoting Kevin Chisholm <kchisholm at ca.inter.net>:
>
>> .... the greater objective of the Stoves List, which
>> seemingly is to configure simple, low cost, more efficient, cooking and
>> heating stoves that provide a reduced health hazard to the user. If this 
>> is
>> an acceptable definition of the purpose of the stoves list, ...
>
> Correct above, but incorrect below:
>
>> ...the T-LUD
>> stoves, which were fundamentally designed for the North American Camping
>> Market, would seem to be a fringe stove technology.
>
> Tom Reed conceptualized and operationalized the CONTROLLED and useful form 
> of
> top-lit updraft pyrolytic gasification (now called T-LUD combustion) in 
> 1985
> specifically with developing societies in mind.  10 years later, the 
> well-known
> Reed-Larson stove was presented, again aimed at assisting the needy.  See 
> "A
> WOOD-GAS STOVE FOR DEVELOPING COUNTRIES," and all with natural draft.
> http://bioenergylists.org/stovesdoc/Reed/T1.htm
>
There is no question in my mind that the Reed Stove is brilliant in the way 
it recognizes the requirements for good combustion, and finds a way to put 
them into practise in a very simple way. Indeed it is an excellent stove for 
a situation with availability of a reasonably dense fuel, with the right 
range of "surface area per gram", sized for a reasonable pressure drop , of 
the right moisture content range, and where the cooking requirement can be 
met with a "batch operation."

The fan powered Inverted Down Draft ("IDD") , aka Top Lit Up Draft ("T-LUD") 
is perhaps more on the fringe because it requires a fan, and a source of 
power to run it. A suitable fan to run it might cost $1, but the ongoing 
source for power to operate it might cost $7.50 (TEG's in large volume, at 
cost), or perhaps $10 to $20 for a suitable solar panel and battery for 
recharging.

Poor people who can only afford low cost stoves are building them for an 
"out of pocket cost" of about $1 to $5, they run on indigenous fuel, and 
they meet the local cooking/heating/cultural requirements. While these basic 
stoves have their problems, incremental improvements have significantly 
improved their performance, with relatively little increase in cost. If all 
tehy can afford is $5, and a T-LUD costs them $15, then clearly, the option 
is dead in teh water.

> I met Tom Reed in 2001 when he had a prototype of a forced air unit that
> eventually became the Woodgas Campstove in 2004-05.  Thankfully, Tom did 
> decide
> that a stove for the affluent camper market would at least bring the T-LUD
> technology to more people and to where it can be tested.
>
> Because of Tom's early work, there are today continuing efforts to have 
> T-LUD
> technology meet "the greater objective of the Stoves List" that you so
> accurately stated.

OK, if we take that a few steps further, what is "The Market" for the T-LUD? 
At its present level of development, it is great for affluent campers who 
want to warm a can of food or boil up some tea using twigs found along the 
trail. Is there a need and affordability and the fuel for such a stove in a 
Third World Application?

Much of the talk about the T-LUD on this List is about its efficiency and 
various technical aspects. Very little discussion has been directed toward 
"the cooking and heating task that the User wants to accomplish. There was 
equivalently little discussion about cost to teh User,  the nature of the 
fuels available to these people, and perhaps even less discussion about how 
teh User would keep teh stove operating when the inevitable failure of teh 
fan, wiring, charger, battery, TEG, etc happened.

Tom's IDD stove system, as shown in the above reference, strikes me as a 
very good basic system. It should be possible to configure a simple 
mechanical mechanism for feeding fuel continuously. With a good definition 
of the fuel around which the system was to be designed, then it might be 
possible to configure a very helpful and affordable stove. Perhaps Tom Reed 
can comment on the general extent of use of his IDD system, and what are the 
barriers that presently prevent even more widespread use of it.

Best wishes,

Kevin