<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">List: cc Kevin M</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>1. This is to bring you up-to-date on Kevin McLean’s “zero cost” stove work - that I have learned in the last 4 weeks.. This today is on three (mainly one) new concepts (despite keeping the thread name). It has applicability especially to those working with Rocket stoves - but I am pretty sure he/we can find ways to work also with TLUDs. </div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>2. After Kevin sent me 3 short videos a few days ago, we agreed there could be great benefit to his and everybody’s stove research to get this early work out for discussion. So this is to ask everyone to view Kevin’s annotated 2 minute video on an approach I have not previously seen:</div><div class=""><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="https://drive.google.com/file/d/1EJQEKKkMTQbcKn3kBC1YZ50oqtZPsbym/view" class="">https://drive.google.com/file/d/1EJQEKKkMTQbcKn3kBC1YZ50oqtZPsbym/view</a>. </div><div class=""> I am amazed that so much energy gets to the second pot (and he may develop a 3 pot design, that also looks well worth the relatively small added extra cost). No metals anywhere.</div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Anyone seen this before? </div><div class=""><br class=""></div><div class=""> <span class="Apple-tab-span" style="white-space:pre"> </span>3. I will try to report soon on two other new (to me) very low cost stove improvement areas on which Kevin has also been working - and which I am unaware of any others pursuing: </div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>- adding energy storage using movable hot rocks or bricks (headed to hay baskets maybe?)</div><span class="Apple-tab-span" style="white-space: pre;"> </span>- making char while cooking (and NOT with TLUDs)</div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Can anyone give a lead to these storage and char-making areas?</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>4. The 4th area of our discussions since the message below still seems brand new:<span class="Apple-tab-span" style="white-space:pre"> </span><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>- improved air flow with 3-stones - using "rocks and clay grates” to elevate the fuel.</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>5. Since Kevin is adamant on zero costs to users (and minimum costs allowable when payback time is short), these ideas are not amenable to most companies looking at the 3-stone-user market. Accordingly, Kevin will not be patenting any of this - all 4 areas will be open source.<span class="Apple-tab-span" style="white-space:pre"> </span> <br class=""><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Anyone working on any of these 4 areas? Or know of past results from anywhere?</div><div class=""><br class=""></div><div class="">Ron</div><div class=""><br class=""></div><div class=""><div><br class=""></div></div></div></div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div><br class=""><blockquote type="cite" class=""><div class="">Begin forwarded message:</div><br class="Apple-interchange-newline"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;" class=""><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">From: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class="">Ronal Larson <<a href="mailto:rongretlarson@comcast.net" class="">rongretlarson@comcast.net</a>><br class=""></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;" class=""><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">Subject: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class=""><b class="">Re: [Stoves] Simple Modifications to Traditional Wood Cookstoves - Rocks and Clay Grates</b><br class=""></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;" class=""><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">Date: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class="">March 29, 2019 at 3:01:27 PM MDT<br class=""></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;" class=""><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">To: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class="">Discussion of biomass cooking stoves <<a href="mailto:stoves@lists.bioenergylists.org" class="">stoves@lists.bioenergylists.org</a>><br class=""></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;" class=""><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">Cc: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class="">K McLean <<a href="mailto:info@sun24.solar" class="">info@sun24.solar</a>><br class=""></span></div><br class=""><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">List, cc Kevin</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""></div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><span class="Apple-tab-span" style="white-space:pre"> </span>This is to encourage this list to view the two “Sun24” links given below. Because I was so impressed when I viewed those, I had a nice phone conversation with Kevin yesterday. A few things I learned:</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><span class="Apple-tab-span" style="white-space:pre"> </span> Kevin is a retired lawyer. Retired for only a year, but already in contact with stove-knowledgeable NGOs in many countries. Through them, he is offering - for free - improvements in 3-stone use of doubled efficiency, and improved emssions. Working also with some low-cost rocket designs. Not yet working on TLUDs - but knowledgeable about them, and supportive at the right price. Has stove modifications measured in multiples of 10k, I think (in only a few past months).</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""></div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><span class="Apple-tab-span" style="white-space:pre"> </span>His emphasis on major stove improvements at zero cost (better air delivery), with local NGO support, is something we have been mostly missing in our stove development efforts. Emphasis zero cost - described at these two sites given below.</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""></div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Ron</div><div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Mar 28, 2019, at 9:24 AM, K McLean <<a href="mailto:info@sun24.solar" class="">info@sun24.solar</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="gmail_default" style="font-size:small">Sun24 and its partners operate at the primitive end of the cookstove spectrum.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">We have found that both rocks (or broken clay bricks) and a clay grate improve open-fire wood cookstoves' efficiency. Here are examples of rocks and a clay grate in a three-stone cookstoves:</div><div class="gmail_default" style="font-size:small"><div class=""><span id="cid:ii_jtsqp0pr0" class=""><Rocks in 3-stone.jpg></span><div class=""><span id="cid:ii_jtsqp0r91" class=""><Clay disc grate in 3-stone stove.jpg></span><br class=""></div></div></div><div class="gmail_default" style="font-size:small"></div><div class="gmail_default" style="font-size:small"><a href="https://drive.google.com/file/d/183kPF5DrwIR5mdDhE7xC9AaNJLaorGZt/view?usp=sharing" class="">SNV tested</a> the rocks and clay grate in its open-fire stove. Here are SNV's results:</div><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default"><span class="gmail-il">Rocks</span> vs unmodified open fire</div></div><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default">+30% Thermal efficiency</div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default">-27% Wood fuel used</div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default">-53% CO </div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default">-57% PM </div></div></blockquote><div class="gmail_default" style="font-size:small"><div class="gmail_default"><span class="gmail-il">Clay</span> <span class="gmail-il">grate</span> vs unmodified open fire</div></div><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default"><div class="gmail_default">+52% Thermal efficiency</div></div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default"><div class="gmail_default">-47% Wood fuel used </div></div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default"><div class="gmail_default">-57% CO </div></div></div></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px" class=""><div class="gmail_default" style="font-size:small"><div class="gmail_default"><div class="gmail_default">-58% PM </div><div class="gmail_default"><br class=""></div></div></div></blockquote></blockquote><div class="gmail_default" style="font-size:small">Early user feedback suggests that rocks in traditional charcoal cookstoves also improve efficiency. We are expanding our informal field testing and hope to test in the lab soon.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">Since rocks and broken clay bricks are free and ubiquitous, we only need to disseminate the idea, not a product. We are rapidly disseminating the idea with success in Kenya, Uganda and India by training women group association leaders to train others who then train at the local level. In Kenya and Uganda we are working with the Catholic and Anglican Churches. In just a couple months and at low cost, we have trained tens of thousands of women to use this simple modification. The trainers' feedback is that the users love it.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">Here is our occasionally-but-not-frequently-enough updated <a href="https://docs.google.com/document/d/1ZryS7gQ1q3zKLZPM2KcXdtIHbOYQp4PbloPqMvrlZ5Y/edit?usp=sharing" class="">Cookstoves Overview</a>.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">These cookstove modifications are a transitional first step but they are important.</div><div class="gmail_default" style="font-size:small"><br class=""></div><div class="gmail_default" style="font-size:small">All suggestions are welcome and appreciated.</div><div class=""><br class=""></div><div class=""><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><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="">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=""> </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>
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