<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Andrew:<div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Apologies for first using this response to also go back to yesterday’s original article which was on stoves (but not at all on TLUDs). In re-thinking it last night, the graph they showed would gather a lot more attention for char-making stoves if they had shown a graph where negative results are left and downward. Their negative (costs, not benefits) results are shown (upper right quadrant) where positive results are always expected in economics. This 2017 article you are bringing up again is at <a href="http://pubs.acs.org/doi/pdf/10.1021/acs.est.6b05557" class="">http://pubs.acs.org/doi/pdf/10.1021/acs.est.6b05557</a></div><div class=""><br class=""></div><div class=""><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>I said: <i class="">I hope someone can reproduce their work with char-making stoves which would place some points in the 4th (negative ordinate [negative carbon]) quadrant of their important first page figure. “</i></div><div class=""><span class="Apple-tab-span" style="font-style: italic; white-space: pre;"> </span>What I should have said is that I’d prefer a coordinate system where positive is right and up and negative is left and down. I’ll start when I can to show the difference in this stove article’s unusual and commendable emphasis on climate issues.</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>I also have not given up on future char-making stoves doing much better on the abscissa (health) axis. Bio-LPG would clearly show up as a positive climate result. Can we claim the Bio-LPG, if produced with biochar also might give positive health impacts? I don’t want to make that claim from the usual air quality perspective (where we can make the claim that the negative health impacts are reduced), but to the extent that biochar gives healthier foods, maybe we can make the case for Bio-LPG and even TLUDs belong in a different quadrant than other stoves. It is obvious they can’t be placed in the same quadrant if the climate impacts are positive rather than negative</div></div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Below we seem to be getting quite afield from stoves, but we really aren’t. The article I identified yesterday is important even for TLUDs - just because of the way its terminology hides the <u class="">positive</u> possibility of obtaining carbon <u class="">negativity</u> with little effort (because it wasn’t being considered). I wasn’t paying enough attention to a graph I had not seen before.</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Apologies for taking too many words to say that the TLUD/biochar part of the stove world has a serious positive-negative terminology problem. </div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Next - to answering your questions.</div><div class=""><br class=""><div class=""><br class=""></div><div class=""><div><blockquote type="cite" class=""><div class="">On Sep 5, 2017, at 3:22 AM, Andrew Heggie <<a href="mailto:aj.heggie@gmail.com" class="">aj.heggie@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">On 4 September 2017 at 23:25, Ronal W. Larson <<a href="mailto:rongretlarson@comcast.net" class="">rongretlarson@comcast.net</a>> wrote:<br class=""><br class=""><blockquote type="cite" class="">This might be a good time to repeat my favorite stove combination - which<br class="">somewhat coincides with the LPG preference of this article. It is LPG from<br class="">renewable biomass sources -<br class=""></blockquote></div></div></blockquote><div><br class=""></div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: The remainder of this sentence is key from the perspective of this list: “….sources </b>- <i class="">IF (repeat <b class=""><u class="">IF</u></b>) the liquid LPG is made locally AND accompanied by a locally produced biochar."</i><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class="">Ronal surely this is a contradiction in terms Liquid Petroleum Gas?<br class=""></div></div></blockquote><div><br class=""></div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: it would seem so, but the gas can be kept as a liquid under sufficient pressure - as I know you know by your comment two more down.</b><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class="">Normally a mixture of butane and propane.<br class=""><br class="">What is the route for making a biofuel that is liquified under pressure?</div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: I am pretty sure there are many - and I am no expert in this. I am favoring the route proposed by “Cool Planet” - now headquartered near me in Denver. They have raised plenty of funds to co-produce almost any (I think) biofuel and biochar. They are stymied because the price of crude oil has dropped from around $100/Bbl to $40/Bbl. The can beat the former price and not today’s. The site: </b><a href="http://www.coolplanet.com/cool-fuels/overview/" class="">http://www.coolplanet.com/cool-fuels/overview/</a> <b class="">has some of this. Key for me is the co-production of a biofuel and biochar - because this is a stove technology that has a positive (sequestering) climate attribute that other stoves don’t have.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>But, since this is a list on stoves and cooking, I am pretty sure that there are other good liquid fuels, well suited for rural cooking, that are liquid at atmospheric pressures. Mountain climbers seem to use gasoline and diesel - because they are much more widely available than LPG. I suspect there are better liquid fuel choices for cooking - and that all can be co-produced with biochar. </b></div><div><br class=""></div><div><blockquote type="cite" class=""><div class=""><div class="">What advantage has this over small scale anaerobic digestion?.</div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: I am fairly certain these pyrolytic approaches can beat the price - because anaerobic digestion normally takes weeks and therefore large volumes. Biofuels via anaerobic digestion isn’t in the market either. Bioethanol is working - especially in Brazil. But no biochar via that route (although the bagasse can be turned into biochar - I think profitably - as reported at the Corvallis meeting).</b></div><div><b class=""><br class=""></b><blockquote type="cite" class=""><div class=""><div class="">Presumably the feedstock can be more woody and not depend on having<br class="">available volatile solids.<br class=""></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: I believe you have one of the answers. But eventually I think we will see anaerobic digestion replaced because there will be a demand (not present yet) for carbon negativity. </b></div><span class="Apple-tab-span" style="white-space:pre"> </span><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class="">Anaerobic digestion is quite a mature technology within Europe's<br class="">agricultural community and techniques exist for reducing sulphur<br class="">compounds to elemental sulphur within the reactor. In my area where<br class="">mixed agriculture has declined much of the unused land is contract<br class="">cropped to provide maize silage for anaerobic digestion.There are<br class="">provisions for methane produced this way to be injected into the gas<br class="">main but I don't know if it is done yet as the rewards for running an<br class="">electrical generator and feeding that grid are greater.<br class=""></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: TLUD stoves can do the same job much cheaper - and get paid for producing a valuable coproduct: biochar. Making money while cooking is hard to beat as an incentive.</b></div><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class="">I have a friend that runs a farm and cheese making factory , the<br class="">wastes from which combined with tonnes more silage and sugar beet to<br class="">buffer the conditions in the digester are digested and ged to a genset<br class="">constanly feeding 100kW into the grid.<br class=""><br class="">He pipes some gas into the cheesemaking and his home for cooking.</div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: A.D. Karve of this list has done wonderful work on cooking along these lines. Same problem - not addressing the need for carbon negativity (and - without competition - improved soils and higher NPP).</b></div><div><b class=""><br class=""></b><blockquote type="cite" class=""><div class=""><div class="">It's come a long way since I read a pamphlet called "composting" by<br class="">Ram Bukh Singh in 1970<br class=""></div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: Our companion biochar list has had a lot on this topic. I predict a trend towards less of the waste biomass resource going into compost and more into biochar. Reasons: better economics and the much needed carbon negativity.</b><br class=""><div><br class=""></div><span class="Apple-tab-span" style="white-space:pre"> </span><br class=""><blockquote type="cite" class=""><div class=""><div class="">N:B: there is a digestion bioenergy list but it has been quiet since May.<br class=""></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL: Similar for the sister list called gasification. </b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span> I guess those two are not needing new ideas and promotion - at least from those who are interested in helping the half of the world population now doing most of their cooking with biomass.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>I ‘d also like to see more with solar cookers on this list. They have a lot to offer by health, climate, and monetary measures. They obviously need a backup that other stove types don’t need - and that should be a stove with more than a carbon-neutral benefit.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Whew. Apologies for too long a response. But I hope all will give some thought on how we report the pluses and minuses of different stoves. Lets try to have plots where positives are upward and to the right. We’ll get better results if we don’t think of new stove types only as different forms of negatives.</b></div><div><b class=""><br class=""></b></div><div><b class="">Ron</b></div><span class="Apple-tab-span" style="white-space:pre"> </span><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class="">Andrew<br class=""><br class="">_______________________________________________<br class="">Stoves mailing list<br class=""><br class="">to Send a Message to the list, use the email address<br class=""><a href="mailto:stoves@lists.bioenergylists.org" class="">stoves@lists.bioenergylists.org</a><br class=""><br class="">to UNSUBSCRIBE or Change your List Settings use the web page<br class="">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org<br class=""><br class="">for more Biomass Cooking Stoves, News and Information see our web site:<br class="">http://stoves.bioenergylists.org/<br class=""><br class=""></div></div></blockquote></div><br class=""></div></div></body></html>