<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body bgcolor="#FFFFFF" text="#000000" style="background-color: rgb(255, 255, 255); line-height: initial;">
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<br>
Dear Paul</div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<br>
</div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
Some good points there. I think I'm order to adequately address the issue of remnant char, it should be first established what the institutional and market interests are. </div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<br>
</div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
Things have to have 'value' to be assessed. That value, or values, must be clearly defined and then suitable metrics selected to report useful information to t<span style="font-size: initial; line-height: initial; text-align: initial;">he rested parties. </span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="font-size: initial; line-height: initial; text-align: initial;"><br>
</span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="font-size: initial; line-height: initial; text-align: initial;">There is little point grabbing any available number. The purpose of the metric must be clear and division of energy into important, reportable fractions </span><span style="line-height: initial;">delineated.
I would not be happy to have any confusion about what is being reported. There are already too many incorrect assumptions about what certain numbers represent. This is a perfect time to create clarity. </span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="line-height: initial;"><br>
</span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="line-height: initial;">Thanks</span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="line-height: initial;">Crispin </span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="line-height: initial;"><br>
</span></div>
<div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">
<span style="line-height: initial;"><br>
</span></div>
<div style="background-color:#FFFFFF">Stovers,<br>
<br>
I appreciate Crispin's detailed message about corrections to the WBT spreadsheet. I suspect that Crispin has it correct, but I leave it to the technical experts about what is right or wrong in each cell of the spreadsheet. (His full message is below, in
case you missed it.)<br>
<br>
There is one specific issue that needs discussion, so I have changed the Subject line (so that we can stick to that single topic). Crispin wrote:<br>
<blockquote type="cite">For stoves that produce a lot of charcoal, it will give a large difference in the performance rating for ‘fuel consumption’, something much closer to its actual consumption. ...<br>
</blockquote>
<blockquote type="cite">For TLUD pyrolysers that SFC number will increase more than 200%. Don’t be shocked. It is now reporting “Fuel Consumed”, not “Energy Theoretically Released turned into a dry fuel mass equivalent”.</blockquote>
I agree with Crispin about "fuel" and "energy" consumptions being different if charcoal is produced. Wood that is changed to charcoal that is not burned is no longer wood, thus his suggested corrections about
<u>fuel </u>consumed are correct. <br>
<br>
But equally true is that the energy consumed should recognize that charcoal is energy that still remains, and therefore should be credited against the total energy of the fuel consumed.
<br>
<br>
The question for the Stove Testing Community is whether what is important is the fuel consumption or the energy consumption for a specific task.
<br>
<br>
Actually BOTH are important, and BOTH should be reported. <br>
<br>
Then the persons evaluating stoves can see both values and make appropriate decisions, such as in the case of communities where wood is in short supply and deforestation is a concern. For example:
<br>
A. If the energy to accomplish the cooking task is the same, and one stove does it with 1 kg of wood and another stove with 1.2 kg of wood but leaving behind charcoal worth the energy in 0.2 kg of wood, then the char-making stove consumed more wood (that is,
more fuel).<br>
<br>
B. But if in that same situation one stove uses 1 kg of wood and another uses (is able to use) 1.5 kg of agricultural residue (such as stems or cobs) and leaves behind some appropriate quantity of charcoal, then the first stove consumed 1 kg of wood and the
char-making stove consumed ZERO kg of wood (but it did use a fuel that did not relate to the deforestation issue).
<br>
<br>
Clearly, the fuel consumption (including knowing the type of fuel) is important, but so is the energy consumption.<br>
<br>
By the way, the created charcoal STILL has its value, whether as a fuel in a charcoal burning stove or as a soil amendment as biochar.<br>
<br>
Concerning the WBT as it currently is established, the WBT fails to provide sufficient information to the evaluators of the stoves. The full data exist in the detailed records of each test, but only a selection is reported, and that selection is BIASED.
Not intentionally biased. Simply biased by not informing enough about the realities of stoves, in this case about stoves that produce charcoal. It is not only about the making of charcoal, it is also about the ability of TLUDs (and some related stoves)
to nicely utilize non-woody biomass.<br>
<br>
This issue was of minor concern before TLUD stoves were seriously considered to be viable for households. The WBT has links back many decades and to early WBT spreadsheets in the mid 2000s. Even in 2010 there was minimal recognition of TLUDs and their char-making
characteristics, certainly not enough recognition for cause concern in the WBT calculations. But things have changed, micro-gasifier cookstoves were highly evident at the recent ETHOS meeting. And there is no going back.
<br>
<br>
Therefore, the WBT and other aspects of the evaluation of stoves (including the Tier system that simplistically yields only a few evaluative numbers) need to be brought up to date.
<br>
<br>
Paul<br>
<pre class="x_moz-signature" cols="72">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a class="x_moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a>
Skype: paultlud Phone: +1-309-452-7072
Website: <a class="x_moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a></pre>
<div class="x_moz-cite-prefix">On 2/26/2015 12:00 PM, Crispin Pemberton-Pigott wrote:<br>
</div>
<blockquote type="cite">For TLUD pyrolysers that SFC number will increase more than 200%. Don’t be shocked. It is now reporting “Fuel Consumed”, not “Energy Theoretically Released turned into a dry fuel mass equivalent”.</blockquote>
<br>
</div>
</body>
</html>