<div dir="ltr">Paul: <br><br>I don't think you want to add the energy value of char if it is going to end up as addition to soil for purported climate benefits or soil productivity benefits. <br><br>This is where the lunacy of reducing everything to CO2e -- the "footprint" blather -- is clearly exposed. There is more to life than fossil CO2 (including respiration and photosynthesis, far far bigger processes than fossil combustion). <br><br>I agree with you - dispense with mass and energy balances and use economic values instead, with "useful thermal energy" valued as the residual.<br><br>Say a $ worth of fuel is ignited, and the value of unburnt fuel is zero or $0.50. Then "useful thermal energy" is a dollar's or 50 cents worth respectively. If someone else pays 50 cents for the latter - if char - then the consumer is made whole. If that revenue is more, then the intervention is "cost-negative". <br><br>One can statistically assign values for non-measurable benefits, and then there is always the key importance of "consumer surplus". If the consumer is willing to spend more - including investment in device or kitchen layout or whatever else - then obviously the benefit is positive. <br><br>Yes, "special values of charcoal" are as important as "special values of good wood". That paper in 1909 Journal of Home Economics did say something like, "Wood has so much better uses than using as fuel." <br><br>But when "renewable biomass" becomes a cult, like CO2e cult, all the nuances are lost. <div><br></div><div>Nikhil<br><br><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><span style="font-family:georgia,serif;font-size:12.8px"><br>--------- </span></div><div style="font-size:12.8px"><font face="georgia, serif">(US +1) 202-568-5831<br><i> </i></font></div></div></div></div></div></div></div>
<br><div class="gmail_quote">On Thu, Jan 12, 2017 at 9:36 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:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
Dear Ron and Crispin, (your two messages are below). Subject
line changed to reflect the content.<br>
<br>
All is in reference to:
<blockquote type="cite">an important stove reporting equation of the
form e3 = e1 / (1- e2). </blockquote>
<br>
I am not great at such equations. But it seems to me that the
letter e is used both as efficiency and as energy.
Whatever. That is not my key point. Rather,<br>
<br>
Both sides have their appropriate strong points. <br>
1. Biomass fuel is consumed, and any remaining charcoal is NOT the
same as the original fuel. So, 100% of the original fuel is gone.
--Crispin is correct about FUEL efficiency.<br>
<br>
2. The charcoal is different from the biomass fuel, but it is still
a viable, usable form of energy that came directly from the original
biomass. So there needs to be some recognition of its ENERGY value.
(If the char has other, non-energy value (such as being good for
filters), and may or may not be eventually consumed as energy, that
is NOT part of this discussion.)<br>
<br>
3. On an ENERGY basis (not fuel basis), only the actual released
energy in the biomass (after subtracting the energy that is still in
the charcoal) should be used to calculate the heat transfer
efficiency of the stove. So the formula (and Ron's second table)
can be considered correct, but it should be perhaps emphasized that
the column heading should be: EE-stove (ENERGY Efficiency of
stove) and is not FE-stove (Fuel efficiency of stove). <br>
<br>
************<br>
I want to pick up on what Crispin wrote:
<blockquote type="cite"><i> Char produced as a co-benefit goes in
the top line, not deducted from the bottom.</i></blockquote>
That realization might have great merit. Can the math-competent
people please do that, and we can see the result. <br>
<br>
Basically it says that ALL of the fuel (in the denominator) is used,
but there are two products in the nominator. I do not know how
to add "Energy captured in the pot" AND "charcoal created (as weight
or volume)". Maybe convert the charcoal into units of energy. And
then add them. And that sum is divided by the energy of the fuel
that is consumed and is no longer in its original biomass form.<br>
<br>
Does this work? Ron, please put another column or two into your
second table and send us the results. <br>
<br>
Another way to look at "efficiency" of fuel and of energy is to
convert everything into monetary amounts.<br>
<br>
$ value of having heated the pot PLUS $ value of the
created char / divided by $ value of the biomass fuel.<br>
<br>
For use in this monetary equation, there can be multiple different
values for each of the 3 variables. <br>
<br>
Extreme values are possible, such as "if the pot does not get hot,
the food is not cooked, and the baby dies" (a very high value for
the heat to the pot.) Also, biomass fuel that is actually
expensive wooden furniture would command a high dollar value. <br>
<br>
On the low side, some biomass fuel could be invasive species that
must be burned, so burning has no cost, and the act of doing the
burning could receive payment. <br>
<br>
But just sticking to common, defendable values, we can find ways to
COMPARE the economic value of using one stove type (that makes char,
for example) with another type that does not. <br>
<br>
This will become increasingly important if and when the world
recognizes special values of charcoal, as in water filters or fo
carbon sequestration (without being biochar into soils) or as
biochar with increased food production (with sequestration as an
added benefit.). <br>
<br>
Stove stuff. I find it interesting.<br>
<br>
Paul<br>
<pre class="gmail-m_7617755805863376267moz-signature" cols="72">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a class="gmail-m_7617755805863376267moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu" target="_blank">psanders@ilstu.edu</a>
Skype: paultlud Phone: <a href="tel:(309)%20452-7072" value="+13094527072" target="_blank">+1-309-452-7072</a>
Website: <a class="gmail-m_7617755805863376267moz-txt-link-abbreviated" href="http://www.drtlud.com" target="_blank">www.drtlud.com <br></a></pre></div></blockquote></div></div></div></div>