[Stoves] Stove testing with and beyond the WBT

Crispin Pemberton-Pigott crispinpigott at gmail.com
Fri Apr 5 05:44:57 CDT 2013


Dear Ron

 

I will attempt to provide a detailed analysis. As you can imagine it takes time and in the end provides a description of a problem. The points Cecil and Paul are making convey the viewpoint that solving a formula problem, while helpful, is not solving conceptual problems.

 

There a number of conceptual problems with the tests which, if not discussed and resolved both as a community an in line with the procedures and protocols of mathematics and social science, mean we may be wasting a great deal of time.

 

The greatest advantage of a toolbox of certified methods, metrics and definitions is that you can do any test you want and get a valid answer that is comparable across platforms. That is why the concept of translations is important. The results of a test that is a specification test are not necessarily comparable of the specification (stating exactly what must be done) produces a bias in the results giving incorrect results for a particular type of stove or fuel. We do not have to ‘just accept’ this state of affairs. By developing the methods correctly a large number of the variables are normalised. 

 

Normalisation is very different from ‘controlling the variables’. Fixing variables is one way to conduct an experiment. Another is to normalise the variables.

 

If I burn a kg of wood, and I get emissions of XXX, that cannot be compared to another stove test using a different type of wood because the heat content of the woods is different. The stove is a thermal device so we are interested in emissions per unit of heat, not per kg of mass of dry mass. Emissions are produced until the thing is cooked or warmed or dried or fried. 

 

Thus describing fuel to Joules is better than using mass of fuels because the energy per unit of mass is different. Controlling the variable means performing all the tests using the same fuel. Normalising the variables means converting them into a common language. 

 

Converting test results into a common language means converting forward to the most correct version we know of. If you convert old WBT 3.0 and 3.1 tests to WBT 4.2.1 you get very different answers to important questions because errors have been corrected and holes in logic closed. 

 

But there is still a long way to go, especially on the subject of concepts. If I give you five litres of water to boil and you boil it, and I ask you how many litres you boiled, and you do not answer, “Five,” we have a problem.

 

Things like that.

 

Regards

Crispin

 

 

 

 

Stoves, Crispin, Paul, Ranyee

 

   1.  Too late for a full response;  more coming.

 

   2.  I like much here, but think you have thought this through with a process that undervalues the production of char.  In particular slide #15 I feel needs modification on both sides.  The standard efficiency formula (char energy subtracted in the denominator) greatly undervalues (not overvalues) the char.  Explanation tomorrow. But briefly, I want to see the char equally valued, so one adds together the carbon neutral and carbon negative production efficiencies.  This is why I went to the GACC and got 10 minutes on this topic.  

     Char-making stoves are getting the shaft now.  I think. (need help) other country procedures are doing it my suggested way.

 

  3.  Slide 15 references a GEF approach which I couldn't find just now in a quick Google.  Can you point me in the right direction?

 

4.  I'd like to do all the computations myself, but will need the assumed fuel and char dry energies, the fuel moisture content, and maybe more.  Can you give me these or point in the right direction?

 

5.  Paul:  I couldn't see a one-pager from Crispin in yours or on your site.

 

Ron




On Apr 4, 2013, at 7:40 PM, "Crispin Pemberton-Pigott" <crispinpigott at gmail.com <mailto:crispinpigott at gmail.com> > wrote:

Dear Paul and Everyone

 

Thanks for devoting so much time to considering the tasks ahead and the alternative paths forward. As you know from your travels we face a huge variety of testing requirements in the field. It is my hope that we can create an agreed scientific platform on which to perform a wide variety of culturally relevant tests that provide normalised results. The Toolbox is a collection of mathematical and cultural tools for measuring performance over a wide range of conditions in diverse cultures. 

 

I am particularly thankful to Cecil Cook for the efforts contributed to developing the social science tools about which we will hear a lot more in the coming months. The cultural appropriateness of stoves is often considered only after a technology has been ‘invented’. Being relevant is a major consideration to marketing campaigns. Sustainability is strongly desired and being sustainable means being simultaneously an improvement and desirable from cultural, economic and environmental points of view. It is by definition a Triple Bottom Line adventure.

 

We will share as much as we can as and when contributors add to the Toolbox. Although it is an inadequate description due to the fact it is brief, I have attached a Powerpoint presentation giving some of the motivating factors for creating the Stove Testing Toolbox and what can be expected from it.

 

Very briefly it intends to provide each tool with the purpose, the metrics, the definitions and the presentation of results for conducting a single testing element of any performance evaluation. While this is implicit in many tests, this divides each task conceptually into discrete segments and creates validated processes that normalises data in order to permit a wide range of tests to give comparable results. It does not specify any tasks, it specifies how a task of that type should be done to get a relevant and correct output.

 

This is widely done in the fields of assessing engineering performance and medical research into diseases and treatments. 

 

Regards

Crispin

 

 

Dear Stovers,

Since the GACC Forum in Cambodia, the topic of stove testing "problems and opportunities" have led me to some thoughts to share, along with some examples.  In the document I wrote:




I believe that a collection and combination of various tests will SERVE MUCH BETTER the needs of the cookstove communities than will the overreliance on the “standard  WBT”, even when that WBT has eventually been corrected for errors in calculation, and formally reviewed openly.


The attached document is for all to read and share with others, and it will be placed on the   www.drtlud.com <http://www.drtlud.com>    and could be at the Stoves website if Tom and Erin think it is worthy.

Paul




Paul S. Anderson, PhD  aka "Dr TLUD"
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> 

 

 

<Stove Testing Toolbox, March 2013 v1.0.pptx>

_______________________________________________
Stoves mailing list

to Send a Message to the list, use the email address
stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 

to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org

for more Biomass Cooking Stoves,  News and Information see our web site:
http://stoves.bioenergylists.org/

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20130405/e8e8841a/attachment.html>


More information about the Stoves mailing list