<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">The main reason for these savings is that the initial load of charcoal matters: This effect was documented very well by Sam Bentson and the rest of the team from Aprovecho many years ago: <div class=""><a href="https://www.researchgate.net/publication/257434335_The_influence_of_initial_fuel_load_on_Fuel_to_Cook_for_batch_loaded_charcoal_cookstoves" class="">https://www.researchgate.net/publication/257434335_The_influence_of_initial_fuel_load_on_Fuel_to_Cook_for_batch_loaded_charcoal_cookstoves</a></div><div class=""><br class=""></div><div class="">If only we could convince people to buy the right size charcoal mbaula we would not need to use fillers like rocks and additional grates to displace the charcoal and have people start with a smaller initial load. </div><div class=""><br class=""><div class="">
<div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;">Best regards</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;">Christa</div><br class="Apple-interchange-newline">
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<div><br class=""><div class="">Am 27.10.2019 um 14:59 schrieb K McLean <<a href="mailto:info@sun24.solar" class="">info@sun24.solar</a>>:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="gmail_default" style="font-size:small">Here is a <a href="https://docs.google.com/document/d/167i50oweyfe23bRMnDSeJwlu0eM4IgTek6IO2C6JPes/edit?usp=sharing" class="">report from Zambia</a> indicating that the rock bed and second metal grate improve the efficiency of the Zambian mbaula (all-metal) charcoal jiko by 41%. Cooking time is also greatly reduced. While these testers have no training, their results are consistent.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">This is such a simple modification that dissemination could be very rapid. I hope some of you can try this. </div></div><br class=""><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Oct 10, 2019 at 1:37 PM K McLean <<a href="mailto:info@sun24.solar" class="">info@sun24.solar</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr" class=""><div class="gmail_default" style="font-size:small"><div dir="ltr" class=""><div class="gmail_default">Listmates,</div><div class="gmail_default"><br class=""></div><div class="gmail_default">Has anyone tried this?</div><div class="gmail_default"><br class=""></div><div class="gmail_default"><div class="gmail_default">We seem to have significantly increased the efficiency of charcoal jikos by putting a bed of rocks on the jiko's grate and putting second metal grate on the rock bed. The charcoal goes on the second metal grate. 2-3 cm rocks work. It works in all metal jikos and clay jikos that we've tested. </div><div class="gmail_default"><br class=""></div><div class="gmail_default">Our testing is early and unscientific, but consistent. 25-50% less fuel used. Here are three reports. The Sierra Leone report has good photos at the bottom.</div><div class="gmail_default"><span id="gmail-m_7143231675533950200m_4206997578200011798gmail-m_-5379600863218226737gmail-m_-1297279476715938052gmail-m_1825955397064429865gmail-docs-internal-guid-10e1cdb9-7fff-27f8-efcc-c921a0e5cc06" class=""><div style="line-height: 1.38; margin-top: 0pt; margin-bottom: 0pt;" class=""><a href="https://drive.google.com/file/d/12MvBKjxq6PCGCcCHAjSYSeVXXvl7jWjD/view?usp=sharing" style="text-decoration-line:none" target="_blank" class=""><span style="font-size:10pt;font-family:Arial;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;text-decoration-line:underline;vertical-align:baseline;white-space:pre-wrap" class="">Sierra Leone</span></a></div><div style="line-height: 1.38; margin-top: 0pt; margin-bottom: 0pt;" class=""><a href="https://drive.google.com/open?id=1zQIY49E1vrfjYl7t5V_shvw70d67QirGWUrbW51tDxo" style="text-decoration-line:none" target="_blank" class=""><span style="font-size:10pt;font-family:Arial;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;text-decoration-line:underline;vertical-align:baseline;white-space:pre-wrap" class="">Uganda</span></a></div><div style="line-height: 1.38; margin-top: 0pt; margin-bottom: 0pt;" class=""><span style="text-decoration-line:underline;font-size:10pt;font-family:Arial;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap" class=""><a href="https://drive.google.com/open?id=1MPwHCwKEVqJvuybKB5Yj39nr8fbcopBP" style="text-decoration-line:none" target="_blank" class="">Kenya (very few rocks)</a></span></div><div style="line-height: 1.38; margin-top: 0pt; margin-bottom: 0pt;" class="">(The report authors are untrained and not native English speakers. Especially the Kenya report contains many errors. Please focus on the consistent final conclusion that a rock bed and second metal grate significantly reduce firewood usage.)</div></span><br class=""></div><div class="gmail_default">This may be a very low cost, very easy way to greatly improved the efficiency of charcoal jikos. I'd like to hear if there is already a body of work on this. Here is my rough drawing:</div><div class="gmail_default"><br class=""></div><div class="gmail_default"><div class=""><div class=""><span id="cid:ii_k1kzflrt1"><20191010_133359.jpg></span><br class=""></div></div></div></div></div></div><div class=""><div dir="ltr" class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div dir="ltr" class=""><div class=""><br class=""></div><div class="">Thank you,<br class=""></div><div class="">Kevin</div><div dir="ltr" class=""><i class=""><br class=""></i></div><div dir="ltr" class=""><i class="">Kevin McLean, President</i></div><div dir="ltr" class=""><div class=""><i class="">Sun24</i></div><div class=""><i class=""><a href="https://sun24.solar/" target="_blank" class="">https://sun24.solar</a> <a href="https://docs.google.com/document/d/1ZryS7gQ1q3zKLZPM2KcXdtIHbOYQp4PbloPqMvrlZ5Y/edit?usp=sharing" target="_blank" class="">Sun24 Cookstoves Overview</a><br class=""></i></div><div class=""><i class="">Tampa, Florida, USA</i></div><div class=""><i class=""><span title="Call with Google Voice" class=""><span title="Call with Google Voice" class=""><span title="Call with Google Voice" class="">+1 (813) 505-3340</span></span></span></i></div><div class=""><br class=""></div><div class=""> <img src="https://docs.google.com/uc?export=download&id=13teZQbnv_6ek6JkEy-4n0yyUVTrl3M2W&revid=0B8zNcWsuiuj3N2RuVFFYL3EvdElxR1lDcm9QQVlaL0F4VnVFPQ" width="200" height="200" class=""> <img src="https://docs.google.com/uc?export=download&id=11k6wcaMcCbykOoLu-Qo4n6Kbdhplk_er&revid=0B8zNcWsuiuj3ejdsRjRXQWU2OW4rVUpwMUx0Q0U0eXgxcStBPQ" width="200" height="200" class=""></div><div class=""><br class=""><i class=""><span title="Call with Google Voice" class=""><span title="Call with Google Voice" class=""><span title="Call with Google Voice" class=""><br class=""><br class=""></span></span></span></i></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
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