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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Oh…I wasn’t talking about sending a stove anywhere. Just mentioning a major upgrade for anything that has side fed sticks and a firs on the floor.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I think the advance is fundamental and can be applied to almost all Asian stoves. I had a couple of grates made, one from cast iron and another couple from re-bar. The round rebar were the best – something to do with the curve and bar spacing but not clear what the full details are.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>The bar spacing is important – about 4 or 5 mm gap and 12mm bars. Generally speaking all grates have bars that are too far apart. As a result of the gaps being large, the char falls through and fails to burn usefully. Jikos with big holes have the same problem.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'>Thanks Crispin,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'>but then issue then is getting what ever here. A stove can cost 25.00 and then it costs 200.00 dollars to ship it here. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'>Michael<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'> <o:p></o:p></span></p></div><div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black;mso-fareast-language:EN-CA'> <o:p></o:p></span></p></div></div><div><p class=MsoPlainText><span style='color:black'>Dear Michael<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'> <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'>There are a couple of other alternatives in use. One is the grate developed by the Rocketworx people in Durban. This seems to be very effective at getting the char burned to ash with very little remnant (means high energy from available fuel). The other is the Improved Keren Stove which was developed at YDD in Indonesia in 2012 that has a tilted grate, very low to the floor. It is about 20mm high on the near (fuel feed) side and 40mm at the back. This also has an air entrance at the back about 20 x 40mm (rectangle). The grate bar spacing is important, as is the shape.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'> <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'>This also burns virtually 100% of the fuel put in. The additional modification to the Keren stove is to lower the pot significantly on the stove body to serve as an excess air controller. The traditional pot rest height was FAR too high - about 25mm. At 7mm it controls the excess air to a reasonable level.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'> <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'>The combination plus one other modification increases the thermal efficiency from —16% to —33%.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'> <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'>Regards<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'>Crispin<o:p></o:p></span></p></div></div></div></div></body></html>