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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'>Dear Crispin,<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></b></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Crispin Pemberton-Pigott<br><b>Sent:</b> Tuesday, September 17, 2013 11:37 AM<br><b>To:</b> 'Discussion of biomass cooking stoves'<br><b>Subject:</b> Re: [Stoves] Charcoal stove design<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dear Frank<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Charcoal largely burns C > CO2 and converts some of it back to CO in the hot zone above the hot coals. </span><b><i><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#003300'>[Frank >] </span></i></b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#003300'>Above the hot coals or in the hot coals? To convert back from CO2 > CO we need more carbon. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If the excess air level is high it can create a lot of CO directly and not burn it. </span><b><i><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#003300'>[Frank >] </span></i></b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#003300'>Is it because the gas is too cool? Molecules are spread too far apart to continue the complete combustion? Not enough hydrogen to aid in supporting continued complete combustion? </span><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The high CO detected in nearly all charcoal stoves is an indication of poor combustion and is not an inherent property of the fuel. Most charcoal stoves are of a brazier type which is basically not a stove at all.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>When wood burns to completion it is burning charcoal somewhere in there, but under better conditions. If you put wood in a ‘charcoal stove’ and lit it there would be pretty bad emissions.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Most people building charcoal stoves try to get the secondary air through the grate from below. Under ideal conditions this can work well, which is to say maybe 3% of the time. The rest of the time, and particularly at low power, the EA is far too high, the fire is cool and CO is produced. We think it makes ‘a lot’ of CO because a) the majority of what could burn is Carbon, and b) we don’t measure H2 so assume it is not there. Duh! There is plenty of both when combustion is poor.<o:p></o:p></span></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'>[Frank >] I find the hydrogen is less than one percent in char. But moisture can increase the hydrogen is not tested directly after drying. Wonder if this water hydrogen is any help in these small stoves?<o:p></o:p></span></i></b></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'>[Frank >] <o:p></o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'>Thanks<o:p></o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'>Frank<o:p></o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><i><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><span lang=EN-CA style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#003300'><o:p> </o:p></span></b></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>There is nothing ‘special’ about burning a high carbon fuel. It requires the same attention to details with respect to the air-fuel ratio and the combustion conditions. Obviously on average there will be more CO2 that H2O in the exhaust because the ratio is different, and it requires more air per kg because there is much less O2 inside the fuel.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>+++++++</span><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'>Paul and Stovers,<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'>I’ve never seen a char stove and, from what I have seen here in the lab working with biomass to char I am surprised it works at all. So there is a lot I don’t understand about this process. You suggest the char is heated when combined with oxygen to produce C > CO then moved to another point and heated again to produce CO > CO2. Seems to me both would create a challenge. Does the char need a little biomass mixed in with it to keep reacting? Or a fan? Does this work the same as burning coal?<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'>Thanks<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'>Frank<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>Frank Shields<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>Control Laboratories; Inc.<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>42 Hangar Way<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>Watsonville, CA 95076<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>(831) 724-5422 tel<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'>(831) 724-3188 fax<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'><a href="mailto:frank@biocharlab.com">frank@biocharlab.com</a><o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#993366'><a href="http://www.controllabs.com">www.controllabs.com</a><o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#993366'><o:p> </o:p></span></b></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> Paul Anderson [<a href="mailto:psanders@ilstu.edu">mailto:psanders@ilstu.edu</a>] <br><b>Sent:</b> Monday, September 16, 2013 11:17 PM<br><b>To:</b> Discussion of biomass cooking stoves<br><b>Cc:</b> Frank Shields<br><b>Subject:</b> Re: [Stoves] Charcoal stove design<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'>Frank and all Stovers,<br><br>When combustible gases are produced (and CO is produced in the charcoal stoves), the air for combusting those gases would be the secondary air.<br><br>In typical charcoal stoves that air comes in over the top rim of the stoves, and is poorly mixed, and the result is massive CO into the room. And very little air can enter when a pot is in place, especially if there is also a pot skirt.<br><br>Work on introducing secondary air via specific openings can be seen some nice work done by GIZ:<br><br><a href="https://energypedia.info/wiki/File:ECLAIR_Benin_stove-factsheet_eng.pdf">https://energypedia.info/wiki/File:ECLAIR_Benin_stove-factsheet_eng.pdf</a> <br><br>More work needs to be done on this topic.<br><br>About reflective shinny surfaces, does anyone have any info that is related to stoves comparing metals (different status of shinny) and clay/mud/ceramic? For example, how much more heat-to-the-pot is gained by using metal versus ceramic, and is that difference sufficient to justify (in part?) the extra cost of metal? High mass ceramic/clay takes up more heat than does the metal, but is it really significantly more?<br><br>Paul<o:p></o:p></p><pre>Doc / Dr TLUD / Prof. Paul S. Anderson, PhD <o:p></o:p></pre><pre>Email: <a href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> <o:p></o:p></pre><pre>Skype: paultlud Phone: +1-309-452-7072<o:p></o:p></pre><pre>Website: <a href="http://www.drtlud.com">www.drtlud.com</a><o:p></o:p></pre><p class=MsoNormal>On 9/16/2013 1:00 PM, Frank Shields wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Stovers and Paul Anderson, </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Since good char burns with little smoke it seems there could be some design improvements from the stove in Paul’s attachment:</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in'>1)<span style='font-size:7.0pt'> </span><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We can use shinny surfaces, perhaps like a bowl under the charcoal, to reflect the heat up to the pot.</span></b><o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in'>2)<span style='font-size:7.0pt'> </span><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best to heat a pot we need a blast of hot air directed at the pot -that is not available with radiant heat. I believe to get char to burn we need the same; a blast of air directed at the char. Perhaps because when the carbon goes to CO or CO2 it releases enough heat to start another reaction IF there is oxygen stuck to that carbon allowing a reaction to take place. If not the heat dissipates and does little. </span></b><o:p></o:p></p><p class=MsoListParagraph><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoListParagraph><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Wondering: if a basket of char fitted with a plate at the bottom set on a spring pressing char up against a top grate. The container sealed such that primary air being drawn is directed through a pipe blasting 2cm from the top of the char bed (vertical pipe through the center of the char). The reflective surface directing heat produced to the pot. Something like that?</span></b><o:p></o:p></p><p class=MsoListParagraph><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoListParagraph><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Also; For char stoves is there ever a secondary? </span></b><o:p></o:p></p><p class=MsoListParagraph><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Frank</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Frank Shields</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Control Laboratories; Inc.</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>42 Hangar Way</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Watsonville, CA 95076</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>(831) 724-5422 tel</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'>(831) 724-3188 fax</span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'><a href="mailto:frank@biocharlab.com">frank@biocharlab.com</a></span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-family:"Calibri","sans-serif";color:#1F497D'><a href="http://www.controllabs.com">www.controllabs.com</a></span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span></b><o:p></o:p></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> Stoves [<a href="mailto:stoves-bounces@lists.bioenergylists.org">mailto:stoves-bounces@lists.bioenergylists.org</a>] <b>On Behalf Of </b>Paul Anderson<br><b>Sent:</b> Monday, September 16, 2013 7:24 AM<br><b>To:</b> Discussion of biomass cooking stoves; James S. Schoner<br><b>Subject:</b> [Stoves] Amount of charcoal for simmering</span><o:p></o:p></p></div></div><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Stovers, (this will also be a "post" at my <a href="http://www.drtlud.com">www.drtlud.com</a> website, BUT all replies and discussions should be directed via the Stoves Listserv. Dr TLUD does NOT carry on separate discussions via comments to his website.)<br><br>I am looking for a calculated answer that could give guidelines about the sizes of charcoal-burning stoves, referring to how much charcoal must be consumed for the cooking tasks.<br><br>Question: How much charcoal is needed (per minute, or per hour, or ??) to maintain a pot (5 liters?) of already-boiling water at the simmer temperature of about 96 deg C?<br><br>So many variables, but the replies can state whatever "givens" or assumptions you wish to make, such as:<br><br>1. Heat transfer efficiency of the stove-pot configuration: Is 30% about typical? And does that vary between clay-mud charcoal stoves vs metal charcoal stoves? Please specify, if your response takes that into account.<br><br>Reference: See <a href="http://search.mywebsearch.com/mywebsearch/redirect.jhtml?searchfor=heat+transfer+efficiency+charcoal+stoves&cb=XQ&p2=%5EXQ%5Exdm002%5ES03729%5Eus&qid=499b92ca6697461da7047b820086bd7d&n=77DE8857&ptb=F7EBB78D-F7A7-4077-B858-0D10F0C7CB0E&si=COjP4cCp0rMCFao7MgodRQUALQ&pg=GGmain&action=pick&ss=sub&pn=1&st=hp&qs=&pr=GG&tpr=hpsb&redirect=mPWsrdz9heamc8iHEhldEVRIIbml7k2%2FvmB8U5crkZmbOTdLROAzdl%2F4ZQYYskvUwjkty6%2BVZ%2BNQiIr863cMN8jdRHpxuJvwsN2u6HPpdnPNB%2BBymTTjJMbwcgCi5H8Q&ord=1&ct=AR&" target="_blank">Experimental study for improving energy <b>efficiency</b> of <b>charcoal stove</b> </a><br><a href="http://nopr.niscair.res.in/bitstream/123456789/3794/1/JSIR%2068%285%29%20412-416.pdf">http://nopr.niscair.res.in/bitstream/123456789/3794/1/JSIR%2068(5)%20412-416.pdf</a><br>with reported efficiencies between 21% and 62%.<br><br>2. Still air, no wind.<br><br>3. Comments on types of pots (Stainless vs aluminum vs other).<br><br>4. Lid or no lid. Probably no lid because so much testing is done with no lid on pot.<br><br>5. Ambient temperature: probably 22 to 27 deg C.<br><br>6. Any other variables.?<br><br>Comments: The question arises because the TLUD stoves (and any other charcoal producing stoves) can be a convenient and low cost source of charcoal for a household. That household has some cooking needs for LOW heat (simmer-type), and a charcoal-burning stove.<br><br>Example from the world of stove testing: a pot with 5 liters brought to boil can be placed onto a charcoal stove for the remaining 45 minutes of the standard water boiling test (WBT). The charcoal could be already red-hot, having been placed in the charcoal stove directly from the TLUD stove that made the charcoal. How much charcoal is needed for that simmering task?<br><br>When we know the amount of charcoal, we can calculate backwards to determine how much raw fuel was needed to make that charcoal. (That amount of raw fuel is approximately 5 X of the charcoal weight.) Example: 100 g of char is produced from 500 g of woody biomass. <br><br>Therefore, about 70% of the energy content of the raw fuel would be available for INITIALLY putting heat into the pot. I think we should assume better than 40% heat transfer efficiency because that is the target for Tier 4 stoves and can be achieved by gas-burning stoves. 40% of 70% is 28%, so round it to 30%. And 30% of the energy content of the raw fuel is how much? 1 kg of wood has 16 MJ, so 500 g has 8 MJ, and 30% would be 2.4 MJ. <br><br>Somebody please complete the calculations: <br><br>A. 2.4 MJ will raise 5 liters (5000 g or ml) of water how many degrees?<br><br>B. How many g or ml of water can be brought to 100 C if starting temp of water is 20 C?<br><br>In the end, I hope we have some understanding about the amount of raw fuel and resultant charcoal needed to accomplish the WBT with minimal waste.<br><br>Paul<o:p></o:p></p><pre>-- <o:p></o:p></pre><pre>Doc / Dr TLUD / Prof. Paul S. Anderson, PhD <o:p></o:p></pre><pre>Email: <a href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> <o:p></o:p></pre><pre>Skype: paultlud Phone: +1-309-452-7072<o:p></o:p></pre><pre>Website: <a href="http://www.drtlud.com">www.drtlud.com</a><o:p></o:p></pre><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p><pre>_______________________________________________<o:p></o:p></pre><pre>Stoves mailing list<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>to Send a Message to the list, use the email address<o:p></o:p></pre><pre><a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>to UNSUBSCRIBE or Change your List Settings use the web page<o:p></o:p></pre><pre><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>for more Biomass Cooking Stoves, News and Information see our web site:<o:p></o:p></pre><pre><a href="http://stoves.bioenergylists.org/">http://stoves.bioenergylists.org/</a><o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><p class=MsoNormal><o:p> </o:p></p></div></body></html>