[Stoves] How big is "a tree"

[Richard Stanley]

George,

The question can be answered only of course of you know the kind of  
trees being cut and the species and regeneration rate etc etc.. Thats  
the academic answer which is of course useless for what you need to  
know with what data you likely have there on the ground versus the  
basic figures needed for your proposal. In seeking a practical and  
workable answer for you , I would offer this much (its of course full  
of caveats but that comes later down the page) .

For want of specific site data, lets assume that the wood fuel used  
locally , would be coming from an ideal source where security is  
assured, and  wastes are minimized : a managed wood lot,  using say,  
any of many varieties of Eucalyptus or other equally sized, equally  
dense species...

Based on this gross assumption, I have the following figures from  a  
Canadian (CIDA) funded wood lot plantation project operating out of  
Lilongwe Malawi in 1997:

Their trees were being harvested at a 9 yr. age, (this was the  
optimum size for the minimum sustainable  rotation: Tree weight on  
average: 65 Kgs

Lets stow that bit away for the moment and  enter stage left  
briquette fuel use : Here,  we make the following assumptions based  
on a roughly 14 year run with its extension in about 15 nations to  
date..

Using our compound lever or any of several other manually operated  
presses, a production team of 4 to 6 individuals, working as a  
microenterprise  , selling briquettes to their local market at a  
sustainable profit margin, AND  unfettered by donor largesse ,  
western zeal and / or subsidized --or intimidated or over run by any  
institutional interests, working-- in other words-- to its optimum in  
direct simple response to its market,  will reach up to 50 families a  
day...

Each person in your climate with its own diet and cooking preferences  
will consume (by well published World BAnk and French research data ,  
1.2kgs per person per day of firewood...
50 families of average 6 persons per family consume 7.2 kgs a day,  
2600 kgs or 40 such wood-lot managed, 9 yr. old, 65 kg trees a year..
At its market of 50 families, the briquette production team  
effectively reduces demand for 2000 such trees a year...

This is extremely conservative because few in that market,   survive  
on a  managed (optimally regenerated) wood-lot fuelwood supply, but  
it gives you a good basis for a proposal perhaps.

Change any one of the production scenarios to remove this  
microenterprise from a simple informal day to day embedded/  
acculturated, informal sector activity (like making and selling  
charcoal for example), and all bets are off...

Hope this helps,

Richard Stanley,
Legacy Foundation
www.legacyfound.org
State of Jefferson



On Feb 28, 2008, at 5:14 AM, George Riegg Gambia wrote:

> Someone??
>
> We are at the moment developing a project in The Gambia involving  
> compressed paper/sawdust bricks.
> I have a "practical" engineering mind so alot of the scientific  
> details go over my head - I do understand principles, what works  
> and how but the academic education is just not there.
> We will be putting together a funding proposal and at present it  
> seems to be very important internationally to know "how many trees  
> do you safe?"
> I know how much wood i will be "saving" by burning our compressed  
> bricks - i.e wood that does not have to be harvested from still  
> living trees.
> But:
> Does anybody know if there is an international "standard tree"??  
> Just in simple terms of kg or tons.
>
> Any input would be greatly appreciated.
> Thanks
> George Riegg
> Paper Recycling Skills Project
> The Gambia
> +220 770 7090
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