<div dir="ltr">Dear Paul,<div><br></div><div>Yes, the pot should be standardized.</div><div><br></div><div>When water is simmered at too high a temperature less water remains. So the stove that can fine tune the power does well.</div><div><br></div><div>In my opinion, the WBT 4.2.3 did help to create better turn down in TLUDs and other stoves because of the above.</div><div><br></div><div>The WBT 4.2.3 is getting better because of constant criticism. It's a good process.</div><div><br></div><div>Expert analysis has been gathered in the ISO process. You could join.</div><div><br></div><div>Sam and I are always pointing out, as many others do, tweaks to create better testing. It's been a long and painstaking process and it has years to go. Tami Bond responded to a hundred (?) open source criticisms and the math has been carefully scrutinized and evolved. </div><div><br></div><div>And the public process continues.</div><div><br></div><div>Best,<br></div><div><br></div><div>Dean<br><div><br></div><div><br></div><div class="gmail_extra"><br><div class="gmail_quote">On Sat, Feb 14, 2015 at 4:25 PM, Paul Anderson <span dir="ltr"><<a href="mailto:psanders@ilstu.edu" target="_blank">psanders@ilstu.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div>Dear Dean, my reply is below:<br>
<pre cols="72">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a href="mailto:psanders@ilstu.edu" target="_blank">psanders@ilstu.edu</a>
Skype: paultlud Phone: <a href="tel:%2B1-309-452-7072" value="+13094527072" target="_blank">+1-309-452-7072</a>
Website: <a href="http://www.drtlud.com" target="_blank">www.drtlud.com</a></pre>
On 2/14/2015 1:06 PM, Dean Still wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">Dear Paul,
<div><br>
</div>
<div>To do well on the Low Power Specific Consumption metrics
the stove has to have a good Turn Down Ratio. In other words,
the stove has to have high power and low power.</div>
</div>
</blockquote>
I totally agree with this. But it is not the whole story of
LPSC. Other factors influence LPSC, especially concerning the
measurement of the variables that are used to make the
calculation. These can include the insulation of the pot (incl.
skirts), lid on pot, pot characteristics such as size, quantity of
water in the pot at the start, and at the finish.<br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>Specific Consumption is based on how much energy was used
to create simmered water. </div>
</div>
</blockquote>
Simmered water is not created. It was already hot at the start of
the simmer phase of testing. We are interested in how much energy
is used to MAINTAIN the required temperature near boiling, but
preferable about 3 degrees C lower than that boiling temperature.
In fact, a super-insulative pot could need barely a flicker of a
flame, and therefore even a well turned-down stove could cause the
water to boil and evaporate. <br>
<blockquote type="cite">
<div dir="ltr">
<div>If the stove only operates at high power there is more
steam made and [at the end of testing] less simmered water
remains....</div>
</div>
</blockquote>
that is true. but continue.<br>
<blockquote type="cite">
<div dir="ltr">
<div> ..... so energy was used to create less product.</div>
</div>
</blockquote>
Stove simmering is not creating a product. It is maintaining a
temperature. The steam that is driven off does not represent loss
of "product" which should be understood to be "cooked food" (and not
meaning water that can be added to the pot by any attentive cook in
a household.)<br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>I like Specific Consumption because it forces stove
designers to make stoves that simmer successfully, not just
boil water. </div>
</div>
</blockquote>
I agree. But the measurement procedures need to accurately
document the ability to have that strong turn-down ratio, without
calculations that can yield ambiguous or mis-leading results.<br>
<blockquote type="cite">
<div dir="ltr">
<div>For example, new TLUDs are better stoves because they have
both high power and low power. In my opinion, the WBT 4.2.3
helped to create these more successful TLUDs.</div>
</div>
</blockquote>
The cause-and-effect relationship is not totally clear. We have
wanted turn-down capabilities in TLUDs for many years. <br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>As Sam says, we are working on a paper showing
characteristics of the WBT 4.2.3 for the ISO work. Knowing the
characteristics lets folks evolve a perfect test. <br>
</div>
</div>
</blockquote>
I question the above wording to "evolve a perfect test" (which is a
test run, not the test procedures.) Maybe the statement should be
that "knowing the characteristics let's folks operate their stoves
in special ways to obtain superior results that are not realistic
for average users." OR "... let's folks 'game the metrics' to
present 'perfected' test-results BASED ON OPERATIONAL PROCEDURES AND
NOT ON IMPROVEMENTS TO THE STOVES THEMSELVES." <br>
<br>
OR it could be that flawed protocols /procedures (such as dividing
by the volume of remaining water after simmering) can yield
numerical results that are questionable and perhaps disadvantageous
to the development of clean cookstoves. <br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>Sam is doing great work as he crunches all the data....</div>
</div>
</blockquote>
absolutely. But we are questioning if the numbers are as valid and
useful as claimed.<br>
<blockquote type="cite">
<div dir="ltr">
<div> and gives ISO real numbers to work with in their
discussions.</div>
</div>
</blockquote>
<br>
Concluding statement: The topic of Low Power Specific Consumption
is too important to just brush aside the stated issues. More
"expert testimony" would be useful, including a mathematical
analysis of the impact of the parts of the calculations. <br>
<br>
Paul<br>
<br>
<br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>Best,</div>
<div><br>
</div>
<div>Dean</div>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Sat, Feb 14, 2015 at 8:18 AM, Paul
Anderson <span dir="ltr"><<a href="mailto:psanders@ilstu.edu" target="_blank">psanders@ilstu.edu</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div>Dear Tom H., and to all who are interested in
proper testing of stoves.<br>
<br>
Your reply about your experiences is helpful. Sounds
like you had qualified testing center do the testing, in
accordance with the procedures that Crispin is
questioning. Please send to me the full details.
Could be off-list, but this is sufficiently important
that we will want the full results known.<br>
<br>
I have a specific case of official testing of one of my
stoves with unfavorable results for Low-Heat Efficiency
(simmering). I will add that into the list of examples
and provide the details very soon.<br>
<br>
I invite anyone else who has something to report about
simmering efficiency to also send details of their
experiences, either favorable or unfavorable or
neutral. <br>
<br>
The examination of the questionable methods about simmer
efficiency might take some days, maybe weeks. But not
the months or years that this debate has been
"simmering". <br>
<br>
Remember: A testing center that properly conducts
testing using an endorsed but possibly flawed procedure
is NOT a culprit. The culprit is the testing protocols,
<u>IF found to be faulty. </u>And we hope that the
testing center people (employees and leaders) who
understand the technical aspects of the calculations
will be among those who can help resolve these serious
issues.<br>
<br>
Even those who developed protocols that are eventually
shown to be faulty are not culprits. Mistakes can be
made. However, the culprits can include those who
advocate a protocol that he or she knows (or reasonably
suspects) to be faulty.<br>
<br>
Paul <br>
<pre cols="72">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a href="mailto:psanders@ilstu.edu" target="_blank">psanders@ilstu.edu</a>
Skype: paultlud Phone: <a href="tel:%2B1-309-452-7072" value="+13094527072" target="_blank">+1-309-452-7072</a>
Website: <a href="http://www.drtlud.com" target="_blank">www.drtlud.com</a></pre>
<br>
</div>
</div>
</blockquote>
</div>
</div>
</blockquote>
<br>
</div>
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