<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<font face="Microsoft JhengHei UI">Hi Kevin<br>
<br>
Very interesting. What's the significance of the hole size and
shape, 25 x 25 x 25 cm? Is it optimal for good combustion, or
simply convenient based on pot size and fuel quantity?<br>
<br>
Best regards<br>
<br>
Robert<br>
</font><br>
<div class="moz-cite-prefix">On 22-Jun-22 5:13 AM, K McLean wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CALxcr-s7UDe+_KgndmB+3rZ_OQA5fvv+WGQQAGJQUmdgZB5A=w@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">
<div class="gmail_default" style="font-size:small">
<div class="gmail_default">Adding a 25x25x25 cm hole to
traditional open-fire cookstoves may end the collection of
firewood from forests in many areas. By piling fuel in the
hole beneath the cookpot and lighting the pile on the top,
the fuel burns long, hot, with no tending and with less
smoke. And by quenching the embers, cooks make biochar.</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">We found that most woody biomass
bigger than thin twigs burns well in the <a
href="https://youtu.be/DmzQFCp2kNI" target="_blank"
moz-do-not-send="true">cooking hole</a>. Firewood the
size that is typically burned in unmodified three stone
cookstoves burns for three hours without tending. Much less
smoke is emitted than from an unmodified three stone
cookstove. A colleague estimates that the amount of wood in
the cooking hole would burn for 30-40 minutes in an
unmodified three stone cookstove. Here's a <a
href="https://drive.google.com/file/d/15V4vTJxO1Lcm0wFzB96pQT9jvgjaXkwh/view?usp=sharing"
moz-do-not-send="true">video</a>. </div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Thick twigs burned without tending
for 1.5 hours. Thick twigs and small branches are abundant
and unused in much of Africa.</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">The cooking hole also works with
crop waste (maize stalks and cobs, cassava stems, banana
peels, bean stems, ...), elephant grass, bamboo, large
sawdust and wood shavings, sawdust briquettes, dung patties
and more. Depending on the fuel, the fire will burn without
tending for 20 minutes to several hours. Here's our <a
href="https://youtu.be/DmzQFCp2kNI" moz-do-not-send="true">training
video</a>.</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Women can:</div>
<blockquote style="margin:0px 0px 0px
40px;border:none;padding:0px">
<div class="gmail_default">- All but stop collecting
firewood.</div>
<div class="gmail_default">- Leave the kitchen to do other
things once they start the fire.</div>
<div class="gmail_default">- Make biochar.</div>
</blockquote>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">And 8-12 common bricks can support
two cookpots over one cooking hole allowing two meals to be
cooked with the same amount of fuel and time it takes to
cook one meal. The time to boil is only a few minutes
longer than for one pot.</div>
<div class="gmail_default"><img
src="cid:part1.Xu9gV3Fw.5w1wghYM@ms1.hinet.net" alt="2
burner drawing.jpg" class="gmail-CToWUd gmail-a6T"
tabindex="0" style="cursor: pointer; outline: 0px;
margin-right: 0px;" width="338" height="263"><br>
</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">In much of Africa, most people know
how to make bricks. We show them how to make free custom
bricks to line the cooking hole. Here is a <a
href="https://drive.google.com/file/d/1b2WvePKX_ofnELUWhexqQZR4NyCrXxnH/view?usp=sharing"
target="_blank" moz-do-not-send="true">video</a>.</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Kevin McLean</div>
<div class="gmail_default">Sun24</div>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
<a class="moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>
to UNSUBSCRIBE or Change your List Settings use the web page
<a class="moz-txt-link-freetext" href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for more Biomass Cooking Stoves, News and Information see our web site:
<a class="moz-txt-link-freetext" href="http://stoves.bioenergylists.org/">http://stoves.bioenergylists.org/</a>
</pre>
</blockquote>
<br>
</body>
</html>