<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">List cc Crispin</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Being mentioned 3 times, but charcoal and Tiers not being mentioned once, I respond below - with hopes that Crispin can understand the way charcoal numbers should be used in computing a Tier rating - which he (to repeat) he never specifically addresses (only alludes to).</div><div class=""><br class=""></div><br class=""><div><blockquote type="cite" class=""><div class="">On Jan 27, 2018, at 9:14 AM, Crispin Pemberton-Pigott <<a href="mailto:crispinpigott@outlook.com" class="">crispinpigott@outlook.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
<meta http-equiv="Content-Type" content="text/html; charset=windows-1256" class="">
<meta content="text/html; charset=utf-8" class="">
<div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Dear Andrew</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Show me a cook who worries about the amount of energy released from a solid fuel when cooking, and not the amount of fuel. Just one. </div></div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL1: I can agree that there are probably only a few such cooks. But none is probably also the number of real simple solid fuel cookstove users on this list. A better question for both cooks and list members is: “Show me a cook or list member who favors<u class=""> inefficient</u> stoves. Just one”. The Tier system can be viewed as one about inefficiencies.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>I start this with “inefficient” because it is the main point in the rest of this response. We focus on this list on e1 = (dimensionless) efficiency of heat transfer in the WBT and e2 = efficiency of making charcoal (roughly 1.7 times as energy important as weight). We tend to ignore what is the most important if we want to increase either/both e1 or e2, since inefficiency, i = 1- e1- e2. Now the question that Crispin has trouble with is how should knowing e1 and e2 (and we know both with remarkable precision through any of the WBT’s) give us the e3 needed by the Tier system?. I say remarkable, because I would be happy with 2 or 3% accuracy and repeatability - and the testers do better than that. The e3 answer for Tier purposes is below. Crispin has given no equations for the alternative e3 numbers he cites below - only (inaccurate) assumptions of what I would say.<br class=""></b><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
After finding one, maybe it is Ron, ask if they want the actual energy released, or a vague, misrepresentative number. </div></div></div></blockquote><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL2: Obviously rhetorical - who can want “<i class="">a vague, misrepresentative number”? </i>But NO - I would not be happy with only the “<i class="">actual energy released”. </i></b></div><div><b class="">Despite the best efforts of Xavier and Crispin to discredit the almost approved WG2 methodology, it seems virtually impossible for there to not be a continuation (probably improved, maybe harder) of both an approved WBT and some type of Tier structure. What I want is more than “<i class="">actual energy released”. </i>I want the energy that could have been released if e2 (= percent energy in the char) were zero. That is what is the existing protocol calls for and that I am trying to protect and justify below. </b></div><div><b class=""><i class=""><br class=""></i></b><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
The amazing things about the WBT are the incompetence with which it was created and later, defended, and the effort put into not correcting it, but preserving it as a monument to…what exactly?</div></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL3: None of that sentence is worth responding to.</b></div><br class=""><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Ron doesn’t really want to preserve the WBT, he wants to rate stoves that have a fuel efficiency of 20% to be reported to be 40%.</div></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL4: It is useless for me (the culprit) to ask for a cite for this claim on what “<i class="">he wants</i>”. This is basically a statement that a Crispin doesn’t understand how to use e2. The largest possible number I have ever seen for e2 is 0.4, but lets call it 0.5. In my experience, e2 is around .3. If you use either of the equations I have been repeating this week - (and is in the main WBT protocols and always has been) then e3 (the predicted efficiency if the stove could produce no char) would be e3 = e1/(1-e2) Eq. 1</b></div><div><b class="">and e3 = 1/(1+i/e1) Eq. </b><b class="">2</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>To use the second form, we need the inefficiency, </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>i = 1 - e1 - e2 Eq.3 </b></div><div><b class="">and for Crispin’s claim of what I believe: </b></div><div><b class=""> <span class="Apple-tab-span" style="white-space:pre"> </span><span class="Apple-tab-span" style="white-space:pre"> </span>i =1-.2-.5 = .3 Eq.4 (for the “impossible” case) and </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>i = 1-.2-.3 = .5 Eq. 5 (for “my” version of Crispin’s case).</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>So if e2 is .5 (impossibly high) we would get for the Tier number, using Eq 4</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span> e3 = 0.2/(1-.5) = .4 Eq. 6 (using Eq 1), and </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>e3 = 1/(1+.3/.2) = 1/2.5 = .4. Eq. 7 (using Eq. 2)</b></div><div><b class=""><br class=""></b></div><div><b class="">So we see that Crispin attributes to me a 40% efficiency (without explaining how he got there) that is solely based on (the incorrect statement of) me claiming 50% efficiency for char making - which I never have said and I have above said is not possible - even if e1 were zero.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>For completeness, I could/would not have stated that Crispin doesn’t understand the equation to be used for Tiers if he had used my preferred example inefficiency number of I = 0.5. Then instead of e3 = 0.4, he should have stated that I would expect (not “<i class="">want</i>”) a Tier rating of:</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>e3 = 1/(1+i/e1) = 1/(1+.5/.2) = 1/3.5 = .29 Eq, 8 (a LONG way from his claim that I have been promoting 0.4)</b></div><br class=""><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
That fuel efficiency metric will be used to calculate the reduction in the harvesting of unsustainably harvested forests by improved stoves accessing CDM funding. </div></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL5: Another sentence that is so illogical as to warrant another “no comment” as in [RWL3. </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>However I have to say that the figure e3 now used in the Tiers is much more logical than this statement about his proposed “<i class="">fuel efficiency metric” (which is NOT an e3)</i>. </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>We should be thinking both sustainably and unsustainably harvested forests. </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>I see no reason to suddenly bring “<i class="">CDM funding"</i> into this discussion</b></div><br class=""><blockquote type="cite" class=""><div class=""><div class=""><div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">A stove that reduces fuel cutting by 1/2, Ron wants to be rated as reducing it by 3/4. </div></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL6: Hmm. How did Crispin come up with 3/4 (even if one can figure out what he means by that BIG reduction - meaning what is left must be 1-3/4-= 1/4). Before trying to figure that out, I need to remind the list that when I first introduced a char-making stove design in November, 1995 (on a predecessor of this list) - there was no talk at all of biochar, only char . My intent solely was to save forests from the roughly 15% efficiency of making char (often illegally) in earth kilns.</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>So my first interpretation of this strange sentence was that “it” meant “fuel cutting” - but that has already been defined as “1/2”.</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>So starting with the first clause - which says some unidentified stove <i class="">“reduces fuel cutting by 1/2”</i> - so maybe he means e1’ (the value after using the new stove) is (e1)/2. (This still a guess, since Crispin feels no need for symbols.)</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>Then since the second clause refers to RWL - and I have been (incorrectly) advertised as believing in a doubling of e3 over e1 - I guess now that Crispin is saying here that </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>3/4 = 1 - (1/2)*(1/2). Eq. 9 - </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span> I don’ t know what set of symbols to give - so will ask Crispin to tell us what might refer to my symbols e1, e2, e3, and i )</b></div><div><b class=""> This is indeed an identity. But I don’t want to be identified as recommending either “1/2” term - nor the equation that produces the “3/4” either.</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>[RWL7:<span class="Apple-tab-span" style="white-space:pre"> </span>Let me try to generate an RWL number equivalent to Crispin’s “3/4”. A pretty reasonable example is where </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>e1 = e2 = i = 1/3, Eq 10 (assumption</b></div><div><b class="">then </b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>e3 = 1/2 Eq.11 </b><b class="">(Readers - please check my e3, using both above two equations Eq. 1 and Eq. 2). </b></div><div><b class=""> Note that this (overall) Tier efficiency e3 (when the stove produces no char) was decreased to 1/2 from the e1 +e2 value of 2/3. My e3 of 1/2 is not the claimed doubling that Crispin claims (“claims” because he shows us no equations - only results).</b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>So the WG2 e3 value of 1/2 (if we ignore everything about char-making) is larger by 1/6 than the e1 value of 1/3. So the absolute largest % increase that I could be charged with (still ignoring the forest benefit of making char in a stove) is in the ratio (1/6)/(1/2)= 1/3 or (1/6)/(1/3) = 1/2 - depending on what you want use in the denominator. A non char-making stove requires 1/3 less cutting if one throws away the char (which Crispin apparently feels is likely). So Crispin’s 3/4 is obtained only with hand waving and illogical and inaccurate assumptions </b></div><div><b class=""><br class=""></b></div><div><b class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>[RWL 8: We should also discuss why e3 should be this half-way value between e1=1/3 and the e1+e2 value of 2/3. Why should the stove without char-making not have an efficiency of the full 2/3? (Besides the fact that NO small stove ever gets an e1 that high.) My belief is that it is in the way hydrogen is consumed in the char-making stove. The pyrolysis process is such that the produced char has a much smaller % H2 than any form of “raw” biomass. (And users of the char in soil want it that way.) So the pyrolysis process is providential - we get what both e1 and e2 need to be. Stated another way, e2 has a higher energy content (about 30 MJ/kg) than the input biomass (about 18 MJ/kg). </b></div><div><b class=""><br class=""></b></div><div><span class="Apple-tab-span" style="font-weight: bold; white-space: pre;"> </span><b class="">[RWL9: It might help to say a bit more using weights, assuming 1 kg of input with an initial energy of 18 MJ. If e2 is still 1/3 , then the char must have 6 MJ. An assumed energy density of 30 MJ/kg, means the char must weigh 6/30 = .2 kg. The energy density of the gases going into e1 and i must then be (18-6)/.8 = 15 MJ/kg. Everything balances as we move to find the critical e3 (needed for the Tier computation). The making of char gave up hydrogen to get e1 as high as it was (1/3). When we assume no (char-made) e2 (which was 1/3), then e3 can only jump (by 1/6) from 1/3 to 1/2. There was little H2 impact to give up as e2 went to zero in finding e3.</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>(Note - the actual energy densities in real WG2 reporting are different from these assumed values. But not much different - and the existing WBT instructions are good on how these are to be obtained (unlike some of the competing stove testing approaches.)</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span></b></div><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Do you, Andrew, think that making such a misrepresentation of consumption would be mischievous, or fair, to the funder of the avoidance unsustainable deforestation?</div></div></div></blockquote><div><span class="Apple-tab-span" style="white-space:pre"> </span><b class="">[RWL10: A final rhetorical sentence also not needing comment, once one agrees there has been zero misrepresentation. </b></div><div><b class=""> <span class="Apple-tab-span" style="white-space:pre"> </span> But I write the above for others - not Crispin, whose opinion I expect to remain unchanged by any of the above (I hope of course I am wrong - but I have tried to say most of this before).</b></div><div><b class=""><span class="Apple-tab-span" style="white-space:pre"> </span>I’ll not similarly ask Andrew - but do wonder how he will answer Crispin - with its mischaracterization of my values and methodology? </b></div><div><b class=""><br class=""></b></div><div><b class="">Apologies for length here - obviously, I am trying to influence discussions at ETHOS.</b></div><div><b class=""><br class=""></b></div><div><b class="">Ron</b></div><br class=""><blockquote type="cite" class=""><div class=""><div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Regards </div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Crispin </div>
<div style="width:100%; font-size:initial; font-family:Calibri,'Slate Pro',sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<br class="">
<div class="">
<div dir="ltr" class=""><br class="">
<div class="gmail_extra"><br class="">
<div class="gmail_quote">On 26 January 2018 at 10:51, Crispin Pemberton-Pigott <span dir="ltr" class="">
<<a href="mailto:crispinpigott@outlook.com" target="_blank" class="">crispinpigott@outlook.com</a>></span> wrote:<br class="">
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex; border-left:1px solid rgb(204,204,204); padding-left:1ex">
<div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Dear Anh</div>
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
Other than reporting the energy in the char and it's mass, what else should be reported?</div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<div class="">The only thing that is needed is how much energy was released to do the task, establishing it is a bit troublesome as each species is different and moisture contents vary. With other fuels it's simple, we can weigh a LPG cylinder before and after use and
deduct one from the other to establish the fuel used.<br class="">
</div>
<div class=""><br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex; border-left:1px solid rgb(204,204,204); padding-left:1ex">
<div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
I have never been asked how much energy a stove uses out of the fuel it consumes during the replication of some task. </div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<div class="">So the energy use isn't much relevant to the cook?</div>
<div class=""><br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex; border-left:1px solid rgb(204,204,204); padding-left:1ex">
<div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
<br class="">
</div>
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
People always ask how much fuel a stove needs to 'do something'.Misrepresenting the fuel needed from the available resource to complete a task is mischievous. </div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<br class="">
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex; border-left:1px solid rgb(204,204,204); padding-left:1ex">
<div class="">
<div style="width:100%; font-size:initial; font-family:Calibri,"Slate Pro",sans-serif,sans-serif; color:rgb(31,73,125); text-align:initial; background-color:rgb(255,255,255)" class="">
We should not introduce mischief to our performance evaluations. </div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<div class="">
<div class="">Stop being mischievous then ;-) <br class="">
</div>
<br class="">
</div>
<br class="">
</div>
</div>
</div>
</div>
</div>
_______________________________________________<br class="">Stoves mailing list<br class=""><br class="">to Send a Message to the list, use the email address<br class=""><a href="mailto:stoves@lists.bioenergylists.org" class="">stoves@lists.bioenergylists.org</a><br class=""><br class="">to UNSUBSCRIBE or Change your List Settings use the web page<br class="">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org<br class=""><br class="">for more Biomass Cooking Stoves, News and Information see our web site:<br class="">http://stoves.bioenergylists.org/<br class=""><br class=""></div></blockquote></div><br class=""></body></html>