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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Xavier,</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I had asked a neutral question to get information and felt that I was being treated as a having taken sides against those who disagree with the WBT. I felt under attack. I see that I have treated you unfairly and I apologize.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Kirk H.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sent from <a href="https://go.microsoft.com/fwlink/?LinkId=550986">Mail</a> for Windows 10</p><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='border:none;padding:0in'><b>From: </b><a href="mailto:xav.brandao@gmail.com">Xavier Brandao</a><br><b>Sent: </b>Thursday, January 11, 2018 4:05 AM<br><b>To: </b><a href="mailto:stoves@lists.bioenergylists.org">'Discussion of biomass cooking stoves'</a><br><b>Cc: </b><a href="mailto:gkharris316@comcast.net">gkharris316@comcast.net</a><br><b>Subject: </b>RE: [Stoves] WBT disagrements</p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=FR style='color:black'>Dear Kirk,<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><i><span style='color:black'>“I had to fight tooth and nail with you and Xavier to get tid-bits of information.“<o:p></o:p></span></i></p><p class=MsoNormal><span style='color:black'>I don’t feel it is very fair. I tried my best to answer all your questions, at length, and provide you information. As I told you first when you replied to me off-list, I very much prefer to discuss on-list, as we can all respond and clarify the parts that are not clear. It is good that you posted this message to the List.<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'>Can you please quote where you think I was not willingly providing information to you?<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>This was my answer to your questions off-list:<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><i><span style='color:black'>“</span></i><b><i><span lang=FR>Are the sensors, filters, and computer graphs included in the disagreements ? That is a yes or no question.<o:p></o:p></span></i></b></p><p class=MsoNormal><i><span lang=FR>No, they are not included in the disagreements by the studies.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>They are nevertheless included in the disagreements by Crispin. Note that Crispin criticizes the Aprovecho equipment, the PEMS and LEMS, he says it is not reliable, and he brought evidence on the List.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span lang=FR>Your question is normally, answered. <u>Do you think it is answered?</u> If not, why?</span></i><i><span style='color:black'>“</span></i><i><span lang=FR><o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span style='color:black'>“</span></i><b><i><span lang=FR>According to these two sentences, you are including the sensors and filters (which measure the CO, CO2, PM and PM 2.5), in the WBT dispute.</span></i></b><i><span style='color:black'>“</span></i><i><span lang=FR><o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>No, I didn’t include the sensors and filters which measure the CO, CO2, PM and PM 2.5.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>I included the CO, CO2, PM and PM 2.5 results. It is not the same.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span lang=FR>So, the sensors, filters, and computer graphs are not criticized by the studies that say the WBT is unreliable. They do not say the unreliability comes from that. The unreliability comes from the metrics, statistical approach, calculations. That does not mean the sensors, filters, and computer graphs have been proven reliable. They have simply not been the concern of the studies. <o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>Kirk: you cannot isolate the instruments from the WBT.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>What testing protocol does one use the reliable instruments with? The WBT, or any other testing protocol.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>One cannot use the instruments alone, can he/she? One has to follow a procedure.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>You could for example ask: « is the water included in the disagreements? Is the pot? ».<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>No, like the instruments, they are not. But they are integrate to the protocol. They cannot be dissociated.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span lang=FR>The CO, CO2, PM and PM 2.5 results are obtained by using the sensors and filters (not disputed) with the metrics and calculations and statistical approach (disputed).<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span lang=FR>When you mix a healthy ingredient with a poisonous ingredient, you get a poisonous recipe.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR>(sensors and filters) X (unreliable metrics and calculations and statistical approach) = unreliable results.<o:p></o:p></span></i></p><p class=MsoNormal><i><span lang=FR><o:p> </o:p></span></i></p><p class=MsoNormal><i><span lang=FR>It is the same for a car. A car dashboard may work well, as well as the steering wheel and the clutch. But if there is a major engine failure, the whole car doesn’t start. It will not matter that some part of the car work well: the whole system is not reliable.</span></i><span style='color:black'> “</span><i><span lang=FR><o:p></o:p></span></i></p><p class=MsoNormal><span lang=FR><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>I don’t see what else I could have done to explain. I also provided you again all the links to the studies about the WBT issues. You really have to read them.<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Kirk, you said:<o:p></o:p></span></p><p class=MsoNormal><i>“I also believe in different standards for different purposes.“<o:p></o:p></i></p><p class=MsoNormal>An utterly unreliable standard serves no purpose. A broken tool serves no purpose at all. It can bring no good. As Philip says, a clock that doesn’t tell the time doesn’t help anyone.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><i>“Perfection is not always needed.”<o:p></o:p></i></p><p class=MsoNormal>We are not talking about being perfect. The WBT is not “not perfect”: it is absolutely broken. No testing protocol is perfect, but the WBT is the only one being that unreliable.<o:p></o:p></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><i><span style='color:black'>“</span></i><i>The WBT does very well for what I need. It tells me if a change in the stove is helpful or not. Whether or not it is perfect science is not important for my interests.“<o:p></o:p></i></p><p class=MsoNormal>It actually isn’t helping you, even if it is not easy to see.<o:p></o:p></p><p class=MsoNormal>It is actually really important for your interests, if you want to make stoves that perform well.<span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><i>“I use it because it is available for me in a lab, whereas the other protocols are not.”<o:p></o:p></i></p><p class=MsoNormal>They are available, right now. They have always been. They are available here:<o:p></o:p></p><p class=MsoNormal><span lang=FR><a href="https://drive.google.com/drive/folders/0B5rmmRmIsdlnQlRQX3A1cXVOQ3M?usp=sharing">https://drive.google.com/drive/folders/0B5rmmRmIsdlnQlRQX3A1cXVOQ3M?usp=sharing</a> </span><i><o:p></o:p></i></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You asked me what were the labs performing the alternative tests, and at what costs, as I said to you, I am collecting the information and will get back to you.<o:p></o:p></p><p class=MsoNormal>Why do you think they are not available to you where you are?<o:p></o:p></p><p class=MsoNormal><span style='color:black'>Like a WBT, it doesn’t need much equipment to perform a CSI test. You could perform it at home probably. <o:p></o:p></span></p><p class=MsoNormal><span style='color:black'>If I don’t forget anything, I think the equipment you need is:<o:p></o:p></span></p><ul style='margin-top:0in' type=circle><li class=MsoListParagraph style='color:black;margin-left:0in;mso-list:l0 level1 lfo1'>A thermocouple connected to a measuring device for determining the water temperature in the cooking vessel<o:p></o:p></li><li class=MsoListParagraph style='color:black;margin-left:0in;mso-list:l0 level1 lfo1'>A ruler or tape measure for measuring the dimensions of the cooking vessel<o:p></o:p></li><li class=MsoListParagraph style='color:black;margin-left:0in;mso-list:l0 level1 lfo1'>A scale of 30 kg capacity with 1 gram resolution for measuring the masses of the cooking vessels and water loads<o:p></o:p></li><li class=MsoListParagraph style='color:black;margin-left:0in;mso-list:l0 level1 lfo1'>A stopwatch<o:p></o:p></li></ul><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal>What do you think is currently preventing you from doing a CSI test?<span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Best,<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Xavier<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=FR style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=FR style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma",sans-serif'>De :</span></b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma",sans-serif'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>De la part de</b> Kirk H.<br><b>Envoyé :</b> mardi 9 janvier 2018 20:12<br><b>À :</b> Discussion of biomass cooking stoves<br><b>Objet :</b> Re: [Stoves] WBT disagrements<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=FR><o:p> </o:p></span></p><p class=MsoNormal>Crispin,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#1F497D'>I think your question was appropriate and the answers were hopefully helpful.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>No, you don’t deserve credit for being helpful. I asked my question and instead of answering it you projected your agenda into me and proceeded to answer your own projections, not my question. Without an answer from you I had to make a guess. You didn’t like my guess and became angry and in that anger actually gave me a partial answer. You proceeded to push your agenda using me as a pawn, but not fully answering my question. I had to fight tooth and nail with you and Xavier to get tid-bits of information. Finally I had enough tid-bits of information to assemble a coherent answer. The credit is mine for fighting for an answer.<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Kirk H.<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sent from <a href="https://go.microsoft.com/fwlink/?LinkId=550986">Mail</a> for Windows 10<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From: </b><a href="mailto:crispinpigott@outlook.com">Crispin Pemberton-Pigott</a><br><b>Sent: </b>Tuesday, January 9, 2018 2:13 AM<br><b>To: </b><a href="mailto:stoves@lists.bioenergylists.org">Kirk H.</a>; <a href="mailto:stoves@lists.bioenergylists.org">Discussion of biomass cooking stoves</a><br><b>Subject: </b>Re: [Stoves] WBT disagrements<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Dear Kirk<o:p></o:p></span></p><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>I think your question was appropriate and the answers were hopefully helpful. There are many lab based systems of measurement and sometimes only a few measurements are necessary to make great progress in improving an existing product. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Something that can be separated is this: Aprovecho is not 'the WBT'. What they do and how they do it is not dependent on using the WBT which is merely a fixed test sequence with a set of measurements and calculations. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Philip's comment about the WBT telling you whether or not the stove is improved is most pertinent. If the test didn't tell you how it performed the first time, getting a different wrong answer later may, or may not, be helpful. This is the crux of the problem. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Tuning a stove requires making refined measurements, not generalizations. A series of small, say, 3% improvements can result in a 12-15% improvement in fuel consumption or power change time, or turn down ratio. If the test cannot reliably tell you the change for better or worse is 1% vs 4%, the results are guiding you by chance. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>A very carefully done experiment must, not should, deliver reproducible results. Prof Lloyd has I think been the most specific on this point, much more than most commenters. As an experimentalist not familiar with small stoves, he was expecting that stove performance tests would deliver the same sort of replicability as other physics experiments. The WBT doesn't do that because of the conceptual errors embedded in what it measures, when, and how it calculates the outputs. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>On the face of it, why should the calculations make a result variable? Dean once posted here that if there is a mistake that is applied to every test, then it is not important. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>The difficulty is that the mistakes manifest errors unequally in different stove types, additional to the variability created by conceptual errors. Prof Lloyd was forced to abandon the WBT in favour of a method without those errors in order to continue his work. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Thank you for participating offlist in the discussions. Xavier are I are discussing the preparation of a spreadsheet with a number of tabs, one each for different versions of the WBT and CCT. Putting in the lab info from a test will create copies of the test on each tab with the different calculations so the outputs can be compared. I think we will be able to find 12 versions of the calculations, maybe 15.<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>We can also prepare one tab without the errors. This will be the formulas to be applied that are developed from first principles as per the HTP/CSI where the requested metric is calculated from only the necessary measurements made to achieve it. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Given the limitation of the test sequence itself,, high, high, low power, it would give 'an answer' that could be used to compare the performance of two slightly different versions of a stove, or different fuels, pots, ambient temperature and so on. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>In South Africa, any kerosene stove tested in Johannesburg or similar altitude must also have an emissions test conducted at a coastal location. Similarly in reverse. The performance on such a pair of tests must be highly reproducible. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Such a comparison sheet can be very helpful for convincing the casual user that only the corrected version should be relied upon. Failing that, we must retire, as there are always going to be those who will not make the effort to understand the technicalities of the field in which they choose to dabble. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>After that comes the issue of contextuality. If the WBT with 'standard wood' is used to develop a stove that will be used to simmer soup burning dung, there is no hope. It would be like perfecting a gasoline engine for 89 octane fuel then operating it with diesel oil. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>All stoves are used in some context so the assessment will be most relevant, even for internal metrics for sub-systems, if the test conditions are relevant to the expected pattern of use. The WBT is advertised as a 'cooking simulation'. That's OK. Pick and report. <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Regards <o:p></o:p></span></p></div><div><p class=MsoNormal style='background:white'><span style='color:#1F497D'>Crispin <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='color:#1F497D'><o:p> </o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>All,<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>I recently asked a question about whether the disagreement with the WBT included the sensors, filters and computer graphing as well as the water boiling portion of the overall test. I have received several responses from Crispin and Xavier (some off list). From all that was said by them I have assembled an answer: The sensors, filters and computer read-outs are part of the WBT, but not part of the disagreement with the WBT. So this disagreement is with a portion of the WBT test, not all of it. Also, I believe that Crispin has a second disagreement that questions whether some sensors and setups are able to provide accurate read-outs. I believe that this is a legitimate concern for scientific study, however I also believe in different standards for different purposes. Perfection is not always needed.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>This is an acceptable answer for me. It is not pro or con to the WBT or any protocol. My question was intentionally neutral. I just wanted to know the extent of the disagreement. <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>My position on the WBT remains neutral. I use it because it is available for me in a lab, whereas the other protocols are not. The WBT does very well for what I need. It tells me if a change in the stove is helpful or not. Whether or not it is perfect science is not important for my interests. <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>I believe that Aprovecho (ARC) plays an important part for wood stove development and education and I remain a supporter. <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Kirk H.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Sent from <a href="https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgo.microsoft.com%2Ffwlink%2F%3FLinkId%3D550986&data=02%7C01%7C%7Cae298e4088bd4d17bcf608d5570c4bc2%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636510632671079450&sdata=sRvB55V8H7%2BEg%2Ble5sqvvCUuMYdSNAqb9HGdcp%2FP9yM%3D&reserved=0">Mail</a> for Windows 10<o:p></o:p></p></div></div><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div id=DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2><p class=MsoNormal><span lang=FR><o:p> </o:p></span></p><table class=MsoNormalTable border=1 cellspacing=3 cellpadding=0 style='border:none;border-top:solid #D3D4DE 1.0pt'><tr><td width=55 style='width:41.25pt;border:none;padding:13.5pt .75pt .75pt .75pt'><p class=MsoNormal><a href="https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient" target="_blank"><span style='text-decoration:none'><img border=0 width=46 height=29 style='width:.4833in;height:.3in' id="_x0000_i1025" src="https://ipmcdn.avast.com/images/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif" alt="https://ipmcdn.avast.com/images/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif"></span></a><o:p></o:p></p></td><td width=470 style='width:352.5pt;border:none;padding:12.75pt .75pt .75pt .75pt'><p class=MsoNormal style='line-height:13.5pt'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:#41424E'>Garanti sans virus. <a href="https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient" target="_blank"><span style='color:#4453EA'>www.avast.com</span></a> <o:p></o:p></span></p></td></tr></table></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>