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</o:shapelayout></xml><![endif]--></head><body 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 Frank<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'>You have captured this correctly:<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 lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>I think we are all in agreement with Crispin the final purpose is to save trees and to Ron it’s important to place a value on the char left over. <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>They are two different questions and they have two different answers. Both have value.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>You suggest we determine the wood used for each burn and after several burns we have the average wet wood used. <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Actually we have a protocol for this and it is included in the <a href="http://tungkuindonesia.org/images/downloads/CSI_Indonesia_Test_Methods_2014-1-14_v7.pdf">Test Method</a>. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>It will take many Runs (I suggest ~ten statistically?) <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We are using three.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>And then we go to the next house and how many more houses, all using the same stove (the variable), to come up with a statistical value. <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>This is not actually necessary. There are ways of using focus group to make a determination that is accurate enough to make a comparative assessment. Remember something very important that changes the number of tests required (a lot):<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We are seeking comparative fuel consumption, not absolute numbers. This can be shortened to a comparative test, not a certified result.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>At the moment we are using a comparative test to pretend the result is ‘certified’, meaning ‘absolute’ but in reality, the lab and the procedure and the number of replications, even the calibration protocols and lab training would not really allow one to claim with precision that the result was ‘certified’ correct. We have to do what we can with the equipment available, in the time we have and in a spirit of fairness. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>It is easy when we are not trying to get a 5% or 10% improvement. As with the stove replacement programme in Mongolia, we only allow into the programme stoves that are at least 90% better than the baseline product. That is a huge difference so there is no quibbling as to whether the product is 15% or 12% better. It has to be 90% to 98% better to be interesting to us. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In the final analysis, the exact reduction a stove gives, say 21% v.s. 25% improvement, is not as important as being sure that lots of people adopt a better stove, and they are happy with it and use it most of the time. Being really sure it is 24% better and only used 30% of the time is not really what we want to see in the final analysis.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>For this reason the social science surveys that were conducted were really good, detailed examination of what is cooked, and when, by whom and so on. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>Then we give all these same houses a different stove for testing. Is this your plan? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Nope. That is not practical. The bottom line is the products have to be much better on emissions, reasonably better on fuel consumption, and bought because people want to own and use them. In other words high adoption. Turning that into numbers is always a nightmare and we do the best we can. In this case it is with a new protocol that is strongly informed by local patterns of use. That should give us more predictable results in the field. Because the social science (social impact potential) has been assessed beforehand, we can make a pretty good estimate of whether or not a stove will be acceptable. One metric is cooking power, another is controllability. A third is lighting speed. Another is cost and durability.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>A lab test using fuel Energy as a proxy reduces the variables such that a lot of tests can be done in a short time at a reasonable cost. Like was done before. The biggest variable is the left over energy after the WBT ended and this can be accurately done using a calorimeter on a dried and ground sample –as done at Aprovecho OR my past suggested E450c method. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>One of the very confusing things that has permeated the stove testing community is the erroneous idea that the heat value in the fuel left over has a great deal of significance. It has significance if you want to know the heat transfer efficiency. It does not have a lot of significance if the fuel is not useful in the next fire. For example, you might accurately determine the heat value of tiny chips of charcoal in the ash. And what would you do with het number? It would not tell you anything about how much fuel it uses because that ‘fuel’ is a ‘mechanical loss’ (meaning energy lost without burning it).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Fuel consumption is not determined by measuring the energy content of fuel left over. It is measured by determine the amount of fuel needed each time the burn cycle is completed. That is all. It is really a lot simpler than people have made out. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>As for the value to be placed on the char left over: The quality of this char ranges from toxic to plants –to- sucking up nitrogen –to- adding heavy metals –to- producing a large plant and doubling production. To place a value one needs to collect a quantity and determine its value –if any for a purpose. <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Well, it might have all sorts of values, but it is not relevant to the amount of fuel needed to start and run the stove the next time. Because the question we have been asked is ‘How much fuel does this stove use, on average, in that community?” we should answer it to the best of our ability.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-family:"Calibri","sans-serif";color:#1F497D'>>…</span><span lang=EN-US style='font-family:"Calibri","sans-serif"'>For marketing we may be able to state that stove such-and-such consistently puts out a char of quality to improve soils, sequester carbon or can be used for char cookers -after collecting a composite of the char from a stove and testing it. <span style='color:#1F497D'><o:p></o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That is all interesting information, supplying answers to different questions, not the one that is most frequently asked.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US 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-US 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-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p></div></body></html>