[Stoves] Celebrate! First-ever international standard for laboratory testing of cookstoves published.

Ronal W. Larson rongretlarson at comcast.net
Tue Jul 3 14:39:14 CDT 2018


Paul and ccs

Shanks for the positive response.  See few inserts.


> On Jul 3, 2018, at 6:31 AM, Paul Anderson <psanders at ilstu.edu> wrote:
> 
> Ron,
> 
> Thanks for that well-stated reply.   I hope that many readers will digest what you have presented.
> 
> My comments are restriced to only the discussion of equations and their meanings.   (How we arrive at 50 million char-making stoves is a vastely dirrerent topic.)
> 
> The explanation by equations might be better understood or at least illustrated with a few sets of number based on actual stove typess (see reference to the triangular graph mentioned in your  message.).   
> 
> You wrote:
>> 
>> To repeat, the equation under discussion is used without apology throughout the new ISO 19867-1 document.  
> Maybe give a few specific references / page numbers.   But I for one will not be checking that.
>> I believe I have stated that the correctness of e3 = A/(B-C) is in part because it is identical to e3 = A/(A+D), where D = inefficiency and B = A+C+D - as can be deduced from viewing what's going on in a triangular diagram.  
> Maybe it is time to show such a triangular diagram (in which any position in the triangle shows the three numbers that total 100%).    What are the three components?    You have 4 letteres   A B C D.   and what does each one mean in the real world?   I am trying to understand the concept of D as  "inefficiency", which is being added to A, but D is a negative number .
	[RWL1:   D is positive.  It is what is left after subtracting A (the desired stove energy) and C (the charcoal energy) from B (the input fuel energy).  The WBT reports A, B, and C.  As you point out, it is easier to think B = 1, and A, C, D are then percentages.

	D is perhaps the most important number of them all, and is rarely reported.  All stovers are trying to make this number small.

	I spent many weeks trying to get something meaningful out of ordinary X, Y, Z orthogonal charts - and finally stumbled on the triangular plot.  Googling for triangular plots via Excel gives a few choices (I haven't found one exactly right).  If someone sends me A, B, and C data - I'll send back the graphical version.

> I am guessing that the produced charcoal (Just just happens to be convieniently called "C") is zero for sstoves that do not produce char and something like 20% if measured as weight or 30% if measured as energy.    Is this making sense?   Please explain further.
	RWL2:   Yes that makes sense.  But I hear 40% for energy is a possibility.

>> And Crispin continues to mis-state what e3 is.  It is NOT the efficiency for the test providing A,B, and C.  It is a statement of what would be expected if char (variable C) had NOT been produced.  	
> Further elaboration on that would be helpful.
	[RWL3.   I don't know more to say.  Sorry.    I'll look for someone else's description of the result of applying this equation.  If not this one for entering a value in the Tiers, then what is the right equation?

Ron


Ron
> 
> Paul
> Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
> Email:  psanders at ilstu.edu <mailto:psanders at ilstu.edu>
> Skype:   paultlud    Phone: +1-309-452-7072
> Website:  www.drtlud.com <http://www.drtlud.com/>
> On 7/3/2018 1:13 AM, Ronal W. Larson wrote:
>> Nikhil,  cc  list and Crispin
>> 
>> See inserts.
>> 
>> 
>>> On Jun 28, 2018, at 8:15 PM, Nikhil Desai <pienergy2008 at gmail.com <mailto:pienergy2008 at gmail.com>> wrote:
>>> 
>>> Ron: 
>>> 
>>> A billion dollar question — what difference does all this make and to whom? 
>> 
>> 	[RWL1:   I respond assuming by "all this" that you mean my 10 responses to Crispin.  Summarizing those 10 is relatively easy - the only (repeat only) sentence below (the second sentence I asked under RWL1) - to which Crispin did not later reply (61 minutes after yours - i.e. at 9:16 PM Mountain time):   I said:   "Please explain what equation you would give for this answer for a stove that has intentionally made char."
>> 	
>> 	Since he chose not to give us an answer on the 28th,  this will give him  (and I hope you and others) another shot at an approach alternative to that in wide and continuing use.   I expect no answer from Crispin, since he apparently disputes the validity of even trying.  To repeat, the equation under discussion is used without apology throughout the new ISO 19867-1 document.  I believe I have stated that the correctness of e3 = A/(B-C) is in part because it is identical to e3 = A/(A+D), where D = inefficiency and B = A+C+D - as can be deduced from viewing what's going on in a triangular diagram.  And Crispin continues to mis-state what e3 is.  It is NOT the efficiency for the test providing A,B, and C.  It is a statement of what would be expected if char (variable C) had NOT been produced.  I ask Crispin again to supply a better statement for what the efficiency would be if char had not been produced.  Ot alternatively, what equation would he use to compare char-making stoves with all others?
>> 
>> 	The above was only to set the stage for my (and I hope to hear from others)  answers to your important questions: "what differences and who cares".   Tor me, the difference is largely in whether we are able to assign tiers.  If you (anyone) don't think it important (or wise or permissible) to compare a char-making stove to a non-char-making stove, you (anyone) will reject tiers.   It is much easier to reject tiers if you can discredit the equation (the only equation) that allows comparisons.   The concept of tiers was endorsed (I think) unanimously in Lima some 5-6 years ago.  And this question was known fully at that time.  I think tiers are critical to stove improvement.
>> 
>> 	I contend that even if there were no such thing as tiers, it would still be helpful to have this denominator equation - as the equation contains the terms showing exactly where the energy is distributed.  If you don't measure the weight, you won't know the energy in the char - and you can have no idea of the true inefficiencies.
>> 
>> 	Lastly - "to whom":   This equation and the tier system it allows is obviously important information to both buyers and sellers.  Char-making started off (early 1990's) being interesting to me as a way of helping remove pressure on forests, where traditional char-making is often now illegal - because traditional char-making is so wasteful (and harmful to the environment in many ways).  Next came a period of selling char-making stoves on health grounds - still the primary interest of many stove activists.  Next came a period of realizing that stoves that make char are also time savers.  And of course, my present emphasis on the carbon-negativity aspects of char-making stoves.  I contend all of these positive attributes that follow from the simple equation A/(B-C) = A/(A+D) should be important to something approaching 100% of the global population.  Who should not want a stove that accomplishes all those ends?
>> 	(Aside - I learned this week of a char-making stove design that has MUCH larger turn-down ratio.  In a month or so, we should all hear more.)
>> 
>> 	
>>> And when will the cooks know?
>> 	[RWL2:   Very shortly after we have international agreement on a tax/fee/subsidy available to technologies that are carbon negative.  When do you think that might occur?  I am guessing maybe five years.  It will occur sooner wherever the benefits of biochar become better known (an example is what we have heard from Julian Winter in Bangladesh).
>> 	But for sure there are cooks already who know - as in the Inyenyeri study with the Mimi Moto forced draft stove (see https://www.inyenyeri.com/development <https://www.inyenyeri.com/development> and http://cleancookstoves.org/resources/552.html <http://cleancookstoves.org/resources/552.html>), and some recent reports on stove acceptance by Paul Anderson (see http://www.drtlud.com/ <http://www.drtlud.com/>).  The Inyenyeri cooks only knew part of the advantages of the stove - emphasizing cleanliness and time savings, but not money earnings (because the needed initial (not perpetual) subsidy or biochar advantage is not yet available..
>> 
>>> I am reminded of a classmate who sought to prove the instability of capitalist system by showing the third derivative of the aggregate production function was of the wrong sign. 
>> 	[RWL3:   I have no idea why this is in here.  I talked many decades ago with Dennis Meadows and another author of "Limits to Growth".  Believing the "Limits" story, I believe your classmate was off in the order of the derivative.   Since I believe there is zero possibility of continuing ever onwards to an infinitely large GNP, without knowing anything about your classmate's project - I might guess the right answer is the first or second derivative, depending on what is being varied.  The point of this answer is of course to emphasize the importance of char-making stoves to getting on to a sustainable path.
>> 	What were you driving at with this story?
>> 	
>> 
>>> Assuming you are correct, when will the first 50 million clean biomass stoves be exclusively used for two years and where? 
>> 	[RWL4:   I consider only the char-making stoves to be clean enough to worry about, so I answer only for char-makers, and accept your further stipulations of 50 Million and 2 years.   This of course depends on my answer to your 2nd question on cooks understanding en masse the benefits of making (not using) charcoal.  The current growth path for biochar is approximately doubling every two years.  With a subsidy near $35/tonne CO2 (already seen in some times and places), then this will approximately allow a 6 month payback if the char can be sold for $200/ton of char (20 cents per kilo of char).
>> 	I am not going to worry about your word "exclusively" - but rather that the char-maker is the primary stove - because it is the cheapest, cleanest, most time-saving stove and I see no reason for a rural low-income user (maybe 2 billion in that category) to use another.  So my guess is about 10 doublings (ten years) to grow from about 50 thousand users to 50 million.  We might be at 50,000 such stoves already, but will be shortly.  It took PV about 50 years to reach cost parity (in the 1970's the cost was $100/Watt);  char-making stoves are already much closer to cost parity.  
>> 	To check  a bit - your 50 million stove number, multiplied by about 4 users per stoves and dividing by about 2 billion potential users is getting up to about 10% acceptance.  I don't expect to stop at 10% when the user can make money (and save time, health bills, forests, etc). 
>> 	
>> 	Again, thanks for allowing me to make my sales pitch for both char-making stoves and biochar - based here on the importance of the equation (and WBT and tier structure) I have assumed you are asking about.
>> 
>> Ron
>> 
>> 
>>> Nikhil
>>> 
>>> ------------------------------------------------------------------------
>>> Nikhil Desai
>>> (US +1) 202 568 5831
>>> Skype: nikhildesai888
>>> 
>>> 
>>> On Thu, Jun 28, 2018 at 3:10 PM, Ronal W. Larson <rongretlarson at comcast.net <mailto:rongretlarson at comcast.net>> wrote:
>>> List and Crispin:
>>> 
>>> 	This is a partial response, due to press of other matters.
>>> 
>>> 	Please see inserts.
>>> 
>>>> On Jun 27, 2018, at 10:07 PM, Crispin Pemberton-Pigott <crispinpigott at outlook.com <mailto:crispinpigott at outlook.com>> wrote:
>>>> 
>>>> Dear Ronal and All
>>>>  
>>>> Just on comment:
>>>>  
>>>> >>“I hope this standard is the last nail in the WBT coffin.”
>>>> >             [RWL:  I hope you are willing to change your mind on "coffin", per the above.  What I do hope will soon be dead is the Chinese stove standard which says to treat intentionally-produced char the same as unburned fuel or ash.  I think the same for the South African standard.   I can think of no reasonable rationale for such a position.
>>>> 
>>>> I think you may be misunderstanding something about how calculations are made in the ISO test method. One of the most important metrics for stove performance is assessing the amount of fuel fed into the stove in order to accomplish a task such as baking 1000 cookies or boiling 200 ears of corn.
>>>> The metric is “Fuel Fed” (please see the list of definitions).
>>> 
>>> 	RWL1:  I suggest you misunderstand my misunderstandings.   Please explain what                                 equation you would give for this answer for a stove that has intentionally made char.  I think you are suggesting here in this answer (and below) that there is nothing wrong with the present Chinese approach to pay zero attention to intentionally produced char.  True? 
>>> 
>>>> The mass of fuel fed was carefully written to capture the quantity of fuel needed to accomplish some cooking task. Whether the stove produces char or not is a secondary point. IT is easy to report the amount of char produced, and there are metrics for doing so. It is the amount of char produced per kg or per dry kg of fuel fed.
>>> 	[RWL2:  You leave out that it is not at all easy to provide the energy (not the weight) of that char.  Both are of interest.
>>>>  
>>>> Importantly, the cheating that has been taking place using the WBT is not brought to an end. If I look for the amount of fuel fed into the stove per replication of some task, be it the standard one or a relevant one, I will find the amount of fuel needed to do so. If there is a secondary product such as condensate, char, heat that can be used for a secondary purpose such as space heating, or electricity, these are all recorded in an appropriate manner.
>>> 	[RWL3:  Is now and was in the WBT 4.2.3 and earlier versions.  Cites on cheating have not been produced to my knowledge.
>>>>  
>>>> The cheat that was with us for so long, claiming as the WBT1.x, 2.x, 3.x and 4.x that a stove did not consume fuel because it emerged from the cooking session in the form of char, is gone, thankfully. Please refer again to the definitions.
>>> 
>>> 	[RWL4:  This is erroneous.  Please give the (exact) language anywhere that suggests the "did not consume" .   Please don't ask others to go find something they don't believe exists.
>>> 	
>>>> That ‘char deducted’ formula that you refer to is an energy calculation that relates to the fraction of energy in the fuel fed that was released (theoretically) during cooking. It no longer refers to the mass of fuel fed, as it once did.
>>> 	[RWL5:  This paragraph makes no sense.  There is no theoretical release in the equation being used to give a number to allow comparing char-making stoves with those that don't.  All the numbers going into that computation are given and all have been in theist WBTs I know about.  In the Chinese official test procedure, the char is wished away.
>>>  
>>>> 
>>>> This is a major advance in testing methods. Only the stove testing groups used the erroneous ‘char-deducted’ formula. When searching the literature for some example elsewhere in industry, not a single one could be found because the claim was fundamentally misrepresentative. That has now been cleared up. 
>>> 
>>> 	[RWL6:  Again a paragraph that makes no sense.  Please give exact language from anywhere on what you are talking about.  I think it is the "denominator equation" - which still exists in the latest ISO version - I think adopted with essentially a unanimous vote of many countries (not individuals).
>>> 
>>>> The remaining mentions of the WBT are for PR purposes only. Not a single voice supporting the use of a “WBT-like” test was raised in the ISO process. In fact it was put to a vote in exactly that form, in those words: “WBT-like”. No one wanted it. Now, it is only for the organisations who supported the WBT for so long to be given enough space for them to quietly drop it while pretending that it was a valid method all along. To do otherwise would be to admit they were cheating donors. We do not have to extract that pound of flesh.
>>> 
>>> 	[RWL7:  This is a long way from what others have told me occurred.  So I will break here to hear from others (who I hope can also join in).  
>>> 	It would help this list to have your explanation of how you know what to be true.
>>>  
>>>> The ISO Standard is not anyone’s standard – it only has meaning when a country adopts it, or adapts it. Any country contemplating adopting this document as a national standard will have to consider how it will be implemented, and whether all of it or some of it will apply. When it comes to things like fuel efficiency, which is important in some regions, it is likely the national standards body will apply its collective mind to what portions of this massive document they will use. As anyone reading it will quickly see, it is unnecessarily complex, and requires numerous pieces of equipment that are very expensive if one is to have a reasonable level of confidence in the result. Because a national standard provides a warranty of performance, it is pointless to have as a test method something that doesn’t provide it.
>>> 	[RWL8:  I claim none of this paragraph is true.  I have skimmed it;  Crispin says he has not.  A country that chooses to ignore a work that has taken such effort will lose a lot of credibility in science circles.  This took many years to balance complexity with completeness.
>>>>  
>>>> People seeking lower cost and more accurate alternatives may consider adapting Indian IS–13152, China’s NB/T 43008 – 2012, or the CSI test method which has been used internationally in some form since 2009.
>>> 	[RWL9:  I repeat my claim that Crispin has kindly repeated above:   "I can think of no reasonable rationale for such a position."    To report results on a stove designed to make char without measuring the char, because the national standard says so,  is unbelievable.  That couldn't happen if offending countries adopt the new ISO procedure.
>>>> 
>>>> 
>>>> The WBT 4.2.3 contained, when it does, some 75 systematic errors as well as its much-discussed conceptual errors. We do not know yet how many are contained in the ISO-19867-1 because it has not been reviewed conceptually or systematically. Because the test method is novel, (untested) problems with its implementation will have to be resolved at the national adoption level, if it turns out to be acceptable ahead of other options.
>>> 	[RWL8:   I have asked for this "75" list several times and do so again.   The ISO document that is being discussed has undergone agonizing review - by top experts.
>>> 
>>>> The problems created by the WBT remain, however, as witnessed by the recent release of the second edition of the Micro-gasifier Handbook which makes barley any mention of testing and includes multiple references to ‘performance’ based on the obviously erroneous fuel consumption claims of the WBT.
>>> 	[RWL9:  How about a specific cite and example quotes?   I claim it quite likely that there is zero error in the consumption claims.
>>>  
>>>> 
>>>> For anyone who is new to this topic I recommend reading the CREEC Lab test of the Quad II stove (featured in that Handbook) which shows that the fuel fed per replication of the test is 1.3 kg (as received) and claims a dry wood fuel consumption of 636 g. I will read it again, but I think the handbook does not address this issue squarely and it must in the next edition. Char production is a secondary benefit and can negatively affect the fuel consumption rate. Advocates should not shy away from discussing it. A good example of how to handle secondary benefits is heating stoves, which are assessed on the basis of the cooking provided, the heat provided, and the combination. Where char is an additional secondary benefit, it should also be listed in the form of carbon mass, if it is for sequestering, energy, if it is for fuel, or total surface per gram if it is for “activated” uses.
>>> 	[RWL10:  Crispin here totally misses everything possible about char-making stoves.  More on this if he wishes and gives cites so we don't waste more time on something agreed upon in the new ISO test procedures. 
>>> 
>>> 	Measuring char-making capabilities of a cook stove that excels in emissions and other ways is probably a real problem if one is into coal-consuming heating stoves.
>>> 
>>> Ron
>>> 
>>>>  
>>>> Regards
>>>> Crispin
>>>>  
>>>> ISO TC-285 WG1, WG2, WG3, WG4.
>>>> P-member SABS TC-1043 
>>> 
>>> 
>> 
>> 
>> 
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