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Dear Tom</div>
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In terms of numbers of stoves selected/affected it is certainly in the millions. I don't think that is too important, by which I mean going forward we need to be clear what is being reported. </div>
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The main failure is the gap between what was being measured and reported, and what the consumer of the information thought they were bing told. This is still the main risk. If someone is told the fuel needed to 'simmer a litre of water' and doesn't know that
it doesn't take any fuel at all to accomplishe this, it could justvbe a retained heat cooker, they are being misled by a poorly name and inappropriately calculated metric. </div>
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To have stove vendors 'comparing performance' on the WBT low power metrics is winding up a clockwork orange. To 'achieve a Tier 4 score on an IWA low power metric is literally meaningless because there is no physical basis for such metrics. They were a hasty
mistake. </div>
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Any stove selected on the basis of an IWA set of targets, and there have been quite a number, is being selected on the basis of a Dice Roll Test. It is, as Jiddu pointed out on this list a couple of years ago, a random number. </div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">With the high power metrics, the main problem is the specific fuel consumption to boil a litre of water. The number doesn't represent the fuel needed per litre boiled and it is any
case incorrectly calculated. So, what's left?</span></div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">The heat transfer efficiency is pretty close to reality, give or take, but it is not called that, it is called the thermal efficiency which normally means the fuel efficiency or the
system efficiency. A designer can use the number but the policy maker cannot because the heat transfer efficiency is not equal to the fuel consumption for a solid fuel burning stove. </span></div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">So, excluding India and China which have never used the WBT, it is just about all the formal projects around. </span></div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">That means all the projects using WBT 3.0, 3.1 and 4.1.2 (which did not have the IWA invalid metrics) and everything after the IWA including the 'corrected' and 'updated' versions
of 4.1.2 made available without noting the changes. Obviously that includes the current version 4.2.3 which produces the invalid IWA metrics for low power. </span></div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">Regards </span></div>
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<span style="font-size: initial; text-align: initial; line-height: initial;">Crispin </span></div>
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<p class="MsoNormal">What proportion of stoves are funded through programs that use current methods for selection? How many households are impacted?
</p>
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<p class="MsoNormal">What proportion of stoves are disseminated by independent individuals and organizations who develop stoves suited to local markets and who ignore, or are independent of, the larger organizations? What are the numbers?
</p>
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<p class="MsoNormal">What is the “cost” of the current procedures in terms of the number of stoves disseminated, the extent of the population affected, and the economic and health impact of the beneficiaries?</p>
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<p class="MsoNormal">How would alternative methods reduce the cost and increase the benefits of improved stoves? By how much?
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<p class="MsoNormal">Tom</p>
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<p class="MsoNormal"> </p>
<p class="MsoNormal"><b>From:</b> Stoves [mailto:stoves-bounces@lists.bioenergylists.org]
<b>On Behalf Of </b>Xavier Brandao<br>
<b>Sent:</b> Friday, September 08, 2017 6:52 AM<br>
<b>To:</b> Frank Shields <franke@cruzio.com><br>
<b>Cc:</b> Discussion of biomass cooking stoves <stoves@lists.bioenergylists.org><br>
<b>Subject:</b> Re: [Stoves] Back into action</p>
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<p class="MsoNormal">Dear Frank,</p>
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<p class="MsoNormal">By WBT program, do you mean protocol?</p>
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<p class="MsoNormal">I still disagree. </p>
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<p class="MsoNormal"><i>"The program allowed any stove maker with a few dollars to have their stove tested and listed along with all others."</i></p>
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<p class="MsoNormal"><i>"It did ‘compare stoves’ and it did allow a stove(s) to be picked from a long list for the Real World."</i></p>
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<p class="MsoNormal">But what good is it if we cannot trust the results?</p>
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<p class="MsoNormal">My Dice Roll Test (DRT) also allows any stove maker to have their stove tested and listed along with all others, it allows to compare stoves, and it is totally free.</p>
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<p class="MsoNormal"><i>"The lab doing the testing made money from the client such that the lab was profitable and could continue."</i></p>
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<p class="MsoNormal">Then these labs were commercially successful and also successful in terms of how much audience they reached. They did consultancy work, were associated to large programmes. There is some success in that.</p>
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<p class="MsoNormal">But they made money "selling results" that were not reliable (note that I don't say that it was done out of malice).</p>
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<p class="MsoNormal">There was no success with the WBT in making meaningful and lasting social and environmental impacts (see the various articles from the press about the failure of the cookstove sector as a whole).</p>
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<p class="MsoNormal">And the most important for all of us, is to change the world, not to make money on testing or consultancy contracts.</p>
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<p class="MsoNormal">So I would say the WBT protocol failed.</p>
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<p class="MsoNormal"> </p>
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<p class="MsoNormal"><i>"If the WBT doesn’t work lets drop the WBT."</i></p>
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<p class="MsoNormal">Amen. Now we have all the proofs the WBT doesn't work.</p>
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<p class="MsoNormal">If anyone can contradict these proofs with solid evidence that it does work, now is the time to discuss and work on it.</p>
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<p class="MsoNormal">Best,</p>
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<p class="MsoNormal">Xavier</p>
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<p class="MsoNormal">On 8 September 2017 at 04:43, Frank Shields <<a href="mailto:franke@cruzio.com">franke@cruzio.com</a>> wrote:</p>
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<p class="MsoNormal">Dear Xavier, Stovers,</p>
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<p class="MsoNormal">On Sep 7, 2017, at 12:46 PM, Xavier Brandao <<a href="mailto:xav.brandao@gmail.com">xav.brandao@gmail.com</a>> wrote:</p>
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<p class="MsoNormal"><i><span lang="FR" style="color:#365F91">“The WBT was a successful program to compare stoves and allow the stoves with the best potential to be picked for further consideration in the real World."</span></i></p>
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<p class="MsoNormal">part one:</p>
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<p class="MsoNormal"><i><span lang="FR" style="color:#365F91">“The WBT was a successful program </span></i></p>
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<p class="MsoNormal"> </p>
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<p class="MsoNormal">The program allowed any stove maker with a few dollars to have their stove tested and listed along with all others. </p>
</div>
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<p class="MsoNormal">The lab doing the testing made money from the client such that the lab was profitable and could continue. . </p>
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<p class="MsoNormal">I call that a successful program.</p>
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<p class="MsoNormal"><i><span lang="FR" style="color:#365F91">to compare stoves and allow the stoves with the best potential to be picked for further consideration in the real World.”</span></i></p>
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<p class="MsoNormal">It did ‘compare stoves’ and it did allow a stove(s) to be picked from a long list for the Real World. </p>
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<p class="MsoNormal">as to “best potential” - well that needed to be worked on. </p>
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<p class="MsoNormal">This is all NORMAL for such a program. Its a set up that is working and designed such that changes can be made to improve on making the system better at determining the stove with the ‘Best Potential’. This is ongoing forever and ever….
Thats how science works!</p>
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<p class="MsoNormal">But this group screwed up. </p>
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<p class="MsoNormal">If the WBT doesn’t work lets drop the WBT. Lets drop the entire successful system in place to make improvements. Now we have no system in place at all. A new stove maker or design that might use electric controls or fans that run off changes
in heat will not see the light of day. Or be very expensive to do the only thing - get some group to field test somewhere. </p>
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<p class="MsoNormal"> </p>
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<p class="MsoNormal">It seems the study that is now being introduced is akin to studying the ‘evolution of mankind’. : )</p>
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<p class="MsoNormal">Regards</p>
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<p class="MsoNormal">Frank</p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">No, it wasn't. The WBT was not successful, it was popular. Very popular. Successful and popular</span><span lang="FR">
<span style="color:#365F91">are not the same.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Stakeholders who used the WBT</span><u><span lang="FR">
<span style="color:#365F91">thought</span></span></u><span lang="FR" style="color:#365F91"> it allowed them to</span><span lang="FR">
<span style="color:#365F91">compare and</span> <span style="color:#365F91">pick the stoves with the</span>
<span style="color:#365F91">best potential for the real world.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Since the metrics were invalid and the results absolutely unreliable, comparing them meant nothing.</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">But sure, the WBT is incredibly simple</span><span lang="FR">
<span style="color:#365F91">to use, and makes one think it can do something it cannot: no wonder it's been popular.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Now, I think</span><span lang="FR">
<span style="color:#365F91">for those who do not want to consider other protocols because the WBT is easy</span>
<span style="color:#365F91">and practical</span> <span style="color:#365F91">to use, I can suggest another testing protocol.</span></span></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">It is actually way easier</span><span lang="FR">
<span style="color:#365F91">in its use than the</span> <span style="color:#365F91">
WBT, so then it is way better.</span></span></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">It is called the Dice Roll Test (DRT).</span></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">Some say</span><span lang="FR">
<span style="color:#365F91">that the WBT</span> <span style="color:#365F91">is legitimate because it's been used for</span>
<span style="color:#365F91">decades. Well the Dice Roll Test has been used by</span>
<span style="color:#365F91">various human civilizations for thousands of years. You cannot beat</span>
<span style="color:#365F91">such legitimacy.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">The DRT is simple, you roll the dice to determine the fuel savings and emissions (CO, PM, PM 2.5) of the stove. Then you record the results on a sheet of paper. That’s it.</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">This allows comparability, and placing stoves into Tiers as well.</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">That's what makes it so great, and you can generate a lot of data in no time.</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Like the WBT, the more tests you do with the DRT, the more probabilities you have that one test will represent accurately the performance. I am sure mathematicians could argue</span><span lang="FR">
<span style="color:#365F91">the approach</span> <span style="color:#365F91">of the</span>
<span style="color:#365F91">protocol</span> <span style="color:#365F91">has</span>
<span style="color:#365F91">some perfectly defendable merits.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">So, based</span><span lang="FR">
<span style="color:#365F91">on the</span> <span style="color:#365F91">above</span>
<span style="color:#365F91">compelling arguments, I recommend that the DRT replaces the WBT starting from now.</span></span></p>
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<p class="MsoNormal"> </p>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">More seriously: testing protocols have to be more than just easy to use. They are testing protocols to produce and disseminate millions of stoves,</span><span lang="FR">
<span style="color:#365F91">for christ sakes,</span> <span style="color:#365F91">
it has to be</span> <span style="color:#365F91">really</span> <span style="color:#365F91">
serious.</span></span></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">It is ok if I need to be in a fully equipped lab rather than in my backyard, and if I need few days rather than one afternoon to do my testing. This is an important matter, it is normal engineers and
researchers have to be mobilized for that. It is</span><span lang="FR"> <span style="color:#365F91">
way</span> <span style="color:#365F91">too important.</span></span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">When did easy became more important than scientifically valid?</span></p>
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<p class="MsoNormal"><i><span lang="FR" style="color:#365F91">"Lets correct these problems and get the WBT back to central to our many faceted program."</span></i></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">Do you think these problems can be corrected Frank?</span></p>
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<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">What would be your approach, for each</span><span lang="FR">
<span style="color:#365F91">issue described below this email, to correct them for sure and once and for all?</span></span></p>
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<p class="MsoNormal"><span lang="FR"><br>
<span style="color:#365F91">Best,</span></span></p>
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<p class="MsoNormal"> </p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Xavier</span></p>
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<p class="MsoNormal"><i><span lang="FR" style="color:#365F91">« Some of WBT critical issues remain unsolved. In particular, the main weakness of the WBT concerns its real-life relevance. As a matter of fact, the protocol prescribes to test the stove for a fixed
combination of burn sequence (high-power and low-power) and pot dimensions. This limits the test relevance to just that particular setting: when any variation of these parameters e which deeply affect the system performance e is introduced, results may significantly
differ. Criticism about WBT concerns also the repeatability of the protocol, with a number of researchers claiming that it would need to be reviewed in terms of accuracy. The WBT is a controlled laboratory test, thus supposed to be characterized by good repeatability
and to be effective in comparing different stove designs. Nevertheless, the choice to bring the water to the boil preventing the use of the lid e that is made in order to better approximate a typical cooking task e is not functional to this purpose. As a matter
of fact, uncertainties related to temperature reading and vaporisation in the boiling region lead to high variability between test replicates. In order to improve the reliability and replicability of the tests, the latest version of the protocol includes the
section “Changes to Testing Conditions to Improve Repeatability”, which refers to different fuels and pot characteristics. However, eventual changes involving other parameters (pot insulation and maximum water temperature), which deeply affect test variability,
are not mentioned. Such problems give evidence of an unsolved conflict between the declared purpose of the WBT (viz. to be a design-phase test, not intended to be representative of real-use performance), and a general tendency to use the results form WBT as
a significant means to select the most appropriate cooking stove for a given context. A lot of debate has been made around formulation of metrics, primarily on thermal efficiency (Table C3), which is often interpreted as the most immediate and distinctive
stove performance parameter. Studies from Bailis et al. highlighted how relying on WBT thermal efficiency outputs, regardless of the relative importance of high and low power cooking tasks among the target population, can lead to misleading interpretations.
Furthermore, Zhang et al. and Jetter et al. questioned the scientific meaningfulness of thermal efficiency at simmering. Indeed, this phase is characterised by highly variable steam production, which represents a heat loss in the energy balance but positively
contributes to the efficiency value in the actual formulation of thermal efficiency. Finally, some unsolved issues concerning statistical significance of data are worth mentioning. WBT 4.2.3 includes “Statistic Lessons for Performance Testing”. The appendix
specifies that the minimum number of test replicates for each model of stove should be three, although it is reported that this number of replicates is not necessarily sufficient to determine a stove performance within a certain confidence interval. Nevertheless,
Wang et al. noticed how a great majority of published studies are performed using a number of replicates that is equal or less than three, perhaps due to a misinterpretation of the Appendix message as “only three tests are needed”, regardless of variability
and confidence interval. Wang et al. investigated this topic using a simplified version of the WBT 3.0 and demonstrated that more than 5 replicates are likely to be required to avoid impractically large 95% confidence intervals and that even more replicates
may be required to demonstrate a statistically significant difference in performance between two or more stoves. »</span></i></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">-----Message d'origine-----<br>
De : Stoves [<a href="mailto:stoves-bounces@lists.bioenergylists.org">mailto:stoves-bounces@lists.bioenergylists.org</a>] De la part de Frank Shields<br>
Envoyé : mercredi 6 septembre 2017 17:03<br>
À : Discussion of biomass cooking stoves<br>
Objet : [Stoves] Back into action</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Stovers,</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">The WBT was a successful program to compare stoves and allow the stoves with the best potential to be picked for further consideration in the real World. It was only flawed in the test method used.
Lets correct these problems and get the WBT back to central to our many faceted program.
</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">1) It needs to relate to the fuel planned to be used. I suggest the energy in the Volatile Fraction to be the total energy released to the secondary. The Fixed energy to be the maximum char making
capability of the fuel. Results of percent energy used (if that is at all important?) is based on the volatile energy fraction and the Percent char produced a percent of the maximum for that biomass. That will please all three groups; TLUD, Rocket and Ron
: ).</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">2) We need to have it measured for the many different tasks that the stove might be used. I suggest developing a Task Cube. This a solid metal (platinum, aluminum, steel, titanium) of something that
will last. Cubed to exact measurements, Drilled and taped to fit a thermistor to record the increase in temperature. Place this block in with different foods being cooked and record the temperature profile. Develop the profile that needs be obtained for each
task. Sell the Task Cubes to labs where they can place them in boiling water or sit on a hot surface then follow the temperature profile to determine if the stove will work for that task and when the task is completed.
</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">So we go from the actual fuel (well sort of) to the actual task (well sort of). The program is (or was) already set up and used so should be quick to get it running again. Purpose it to provide Cecil
Cook (and others) with a list of stoves from an unbiased source and with best chance for success into the field so they can do the things they do. And provide the opportunity for every stove designer to get their stove compared with others.
</span></p>
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<br>
<br>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Thanks</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Frank</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Frank Shields</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Gabilan Laboratory</span></p>
</div>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Keith Day Company, Inc.</span></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91"><a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA%C2%A0+93907+%28831&entry=gmail&source=g" target="_BLANK">1091 Madison Lane</a></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91"><a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA%C2%A0+93907+%28831&entry=gmail&source=g" target="_BLANK">Salinas, CA</a>
<a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA%C2%A0+93907+%28831&entry=gmail&source=g" target="_BLANK">
93907</a></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91"><a href="tel:%28831%29%20246-0417">(831) 246-0417</a> cell</span></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91"><a href="tel:%28831%29%20771-0126">(831) 771-0126</a> office</span></p>
</div>
<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
<br>
</p>
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<p class="MsoNormal"><a href="mailto:franke@cruzio.com"><span lang="FR" style="color:#365F91">franke@cruzio.com</span></a></p>
</div>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">_______________________________________________</span></p>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">Stoves mailing list</span></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">to Send a Message to the list, use the email address</span><span lang="FR">
</span><a href="mailto:stoves@lists.bioenergylists.org"><span lang="FR" style="color:#365F91">stoves@lists.bioenergylists.org</span></a></p>
</div>
<div>
<p class="MsoNormal"><span lang="FR" style="color:#365F91">to UNSUBSCRIBE or Change your List Settings use the web page</span><span lang="FR">
</span><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org" target="_BLANK"><span lang="FR" style="color:#365F91">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</span></a></p>
</div>
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<p class="MsoNormal"><span lang="FR" style="color:#365F91">for more Biomass Cooking Stoves, News and Information see our web site:</span></p>
</div>
<div>
<p class="MsoNormal"><a href="http://stoves.bioenergylists.org/" target="_BLANK"><span lang="FR" style="color:#365F91">http://stoves.bioenergylists.org/</span></a></p>
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<p class="MsoNormal">Thanks</p>
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<p class="MsoNormal">Frank</p>
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<p class="MsoNormal">Frank Shields</p>
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<p class="MsoNormal">Gabilan Laboratory</p>
</div>
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<p class="MsoNormal">Keith Day Company, Inc.</p>
</div>
<div>
<p class="MsoNormal"><a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA+%C2%A093907+%28831&entry=gmail&source=g" target="_BLANK">1091 Madison Lane</a></p>
</div>
<div>
<p class="MsoNormal"><a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA+%C2%A093907+%28831&entry=gmail&source=g" target="_BLANK">Salinas, CA
</a> <a href="https://maps.google.com/?q=1091+Madison+LaneSalinas,+CA+%C2%A093907+%28831&entry=gmail&source=g" target="_BLANK">93907</a></p>
</div>
<div>
<p class="MsoNormal"><a href="tel:%28831%29%20246-0417">(831) 246-0417</a> cell</p>
</div>
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<p class="MsoNormal"><a href="tel:%28831%29%20771-0126">(831) 771-0126</a> office</p>
</div>
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<p class="MsoNormal"><a href="mailto:fShields@keithdaycompany.com">fShields@keithdaycompany.com</a></p>
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<p class="MsoNormal"><a href="mailto:franke@cruzio.com">franke@cruzio.com</a></p>
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