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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Dear Paul<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Yes, and I tried to explain it in a way that agrees with your analysis. If making char for combustion, you would want to have a low formation temperature to leave some volatiles (otherwise it is hard to ignite and you have to light more at a time). If you want biochar it should have a relatively high final temperature to create the surface area. If you want to burn it then burn as much as possible during gasification which makes the transition to burning charcoal gas much easier/less of a system adjustment.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>I hope you noted the comment about running the primary into the side of the fuel near the bottom, not through the bottom plate. This reduces damage to the metal by pushing the heat into the fuel instead of the metal. As the fuel burns away fuel drops from above. When the holes are small it gives the heat getting into the metal a chance to move through creating preheated air.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Crispin,<br><br>For anyone wanting to burn the char in the device, your explanation is fine and is much appreciated.<br><br>The biggest difference in our positions is that I and some others do NOT want to burn the char. Reasons can include wanting it for biochar, or to burn it in a different device later, or to protect the fuel container for the high heat of char-gasification, or for some reason of simplified design such as using less expensive materials of controls, and probably a few more reasons.<br><br>For centuries, one objective of scientifically designed combustion devices was to obtain the maximum of energy possible, and that meant to leave the minimum of carbon behind in with the ashes. But as you pointed out, things have been changing. <br><br>I got started in 2001 with what has become known as TLUDs by Tom Reed. Clean combustion was the feature. The TLUD stoves happened to make charcoal. It was a "by-product" that became a "co-product" that for some is the "main-product". <br><br>Paul<br><br><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>