[Stoves] Stove testing methods

[Kevin Chisholm]

Dear Frank

I think you are on the leading edge of something fundamentally important 
with your proposed fuel testing and standardization program...

If we define a stove as:
"A device to burn biomass to accomplish a desired cooking and/or heating 
task in an environmentally acceptable manner", then the only way we can 
compare stove systems is to clearly define the various aspects of the stoves 
in question.

It seems to me that the fundamental driver in stove design is the nature of 
the available fuel. The stove must be designed to operate on the fuel that 
is available to the end user. How can one possibly compare stoves for use in 
a given area, where the fuel options might be twigs, stickwood, cordwood, 
grass, bagasse, wood chips, sawdust, pellets, fireballs, "prepared fuels", 
dung, coal, kerosene, diesel oil, naphtha, propane, natural gas, biogas, 
wood gas, etc, all with different size considerations, calorific values, air 
requirements, moisture contents, and contaminants?

"When the only tool you have is a hammer, then the only problem you see are 
nails." As it applies to the Stoves List, when the major thrust is on fans, 
it is easy to lose sight of 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, the T-LUD 
stoves, which were fundamentally designed for the North American Camping 
Market, would seem to be a fringe stove technology.

Given that "Fuel is Fundamental", then it makes great sense to start with a 
specification for the fuel, and design the stove around the fuel. Designing 
an elegant stove system first, and then looking for a fuel to feed it is 
going about the problem bass ackwards. In my opinion, the Stove System must 
be designed around the available fuel. If we know the fuel then we can 
design the stove, but first, we must know the fuel.

Your proposed work could be of fundamental value around the World to stove 
designers and agencies concerned about fuel supplies, if done properly. To 
be of greatest value, it should be complete and comprehensive. I would 
suggest that such a task is a much greater work effort than you could 
reasonably contribute from your spare time. Why not consider getting your 
Company to seek out Grant Support  from some Funding Agency to do an 
adequately comprehensive job?

Best wishes,

Kevin



----- Original Message ----- 
From: "frank" <frank at compostlab.com>
To: "Paul S. Anderson" <psanders at ilstu.edu>; <stoves at listserv.repp.org>
Sent: Friday, September 22, 2006 4:11 PM
Subject: Re: [Stoves] Stove testing methods


> Stovers,
>
> Just my two cents regarding stoves using wood-like fuel. I think the
> fuel should be the typical fuel used or can be obtained in the area. We
> should not be testing the 'stove' using a 'standard' fuel because that
> will mean nothing in the real world. I suggest we test the stove-fuel
> combination to determine the best stove for a location. We could list
> the typical fuels and have general requirements for that type of fuel.
> That way we could find the best stove using that type of available fuel.
>
> I am working on a fuel expectations formula that we could use if anyone
> thinks it worthwhile.
> My thinking it will report Usable Carbon Density and Usable Carbon:Air
> ratio in the fuel and Air Porosity of the Fuel stacked. Three
> measurements that we could use as requirements. I am working on a fuel
> list now in my spare time.
>
> It goes something like this:
> We need:
> 1) Density of the fuel 2) Bulk Density of the stack 3) Moisture, 4)
> organic Matter, 5) ash values.
>
> The Organic matter is converted to Organic Carbon OC using a factor.
> There will be one for real woody materials and another for manure type
> materials. I already have this info.
>
> The ash value is converted to a volume measurement. The number is about
> 2.5 to 2.7  g/cm for stony-high mineral materials. (manures)
>
> So we take the density of the fuel and subtract the volume of the water
> and ash. Take the total carbon and subtract from that the heat (carbon)
> required to remove the water. This I am still thinking about. We are
> left with the usable carbon for heating the pot. We determine usable
> carbon per volume of fuel and usable carbon per Air space in the fuel. I
> think this will give an idea how much energy we have in the fuel and an
> idea how the fuel will burn. Then we stack the fuel and how tight or
> loose will indicate how much energy we have under the pot and how the
> fire will act.
>
> I don't want to wast my time on this project if my thinking is flawed or
> there is already a better way to do it. But I do think we need some way
> to regulate or monitor  the energy we put under the pot than just
> suggest a volume of fuel. I will be gone for the next week but may be
> able to finish  the basics in about two weeks- unless it is a waste of
> time or someone else wants to move ahead with it.
>
> Frank
> -- 
> Frank Shields
> Soil Control Lab
> 42 Hangar way
> Watsonville, CA  95076
> (831) 724-5422 tel
> (831) 724-3188 fax
> frank at compostlab.com
> www.compostlab.com