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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'>Dear Bjarne<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='color:#1F497D'>></span>You can find more information on our stove on this link: <u><span style='color:navy'><a href="http://www.treetanz.com/">www.treetanz.com</a></span></u><span style='color:#1F497D'><o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The pellet burning stove is exactly the type of device that would benefit from a few of the lessons learned during the development of the Vesto and now the Anglo SupraNova. I encourage you to follow the development as it progresses. Cecil just engaged the GERES people in Phnom Penh and we like their LS (?) stove as a base.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The Anglo (Angloh) Supra is used quite widely in the sub-continent and has the right layout for easy improvement.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I include one picture only here of the SupraNova – unfired clay in this photo:<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><img border=0 width=333 height=314 id="Picture_x0020_1" src="cid:image001.png@01CDF890.11C11CE0"><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Which shows the basic concept. The Secondary air is provided to the gases just above the fuel and there is sufficient space between the fuel and the pot to allow the flame to (mostly) complete burning. Flames should (ideally) never touch a pot. Although the stove is burning charcoal, it can easily burn biomass pellets.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Looking at the stove on your website, there are easily added features that will increase the combustion efficiency:<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Bring the air into the combustion region immediately above the fuel, horizontally if possible (not on an upward angle). This you can do by cutting slots in the top wall of the fuel chamber and closing the secondary airway at the top, forcing the air inwards. You could instead leave a ring-gap instead of slots at the top of the chamber wall. The air gap should be about 4 to 5mm high between the top of the chamber wall and the ring. Radius the outside edge of the chamber wall but not the inside one. Leave it sharp and flat. This is the approach used in the POCA and a couple of other stoves.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Raise the pot but not by increasing the pot rest height, raise the whole outer shell but not the inner chamber. The pot rest should be no more than 8mm high.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Use the primary air holes to control the power you want and then adjust the secondary air gap to give about 100% excess air when running at full power. That is an O2 level in the exiting gases of 10 to 11%. It should not be less than 7% at any time.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In the photo above, the holes are too large. If you go with the ‘holes’ approach there is a balance to be achieved between the number and the area of each. The diameter of the chamber is involved.<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I am interested to hear if you try these modifications. You may notice a hotter burning centre region with more radiation that before, especially early in the burn. The lighting cone will of course make ignition rapid (and much less initial smoke).<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards<o:p></o:p></span></p><p style='margin-bottom:0mm;margin-bottom:.0001pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Crispin<o:p></o:p></span></p></div></body></html>