[Stoves] Examples of results of simmer efficiency Re: [Ethos] Additional presentations at ETHOS 2015

Philip Lloyd plloyd at mweb.co.za
Tue Feb 24 23:57:40 CST 2015


I have re-read this to the end, and I think others should do so too – it has a lot of good sense.  Thank you, Cecil.

 

Prof Philip Lloyd

Energy Institute

Cape Peninsula University of Technology

PO Box 652, Cape Town 8000

Tel:021 460 4216

Fax:021 460 3828

Cell: 083 441 5247

 

 

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Cecil Cook
Sent: 16 February 2015 11:18
To: Discussion of biomass cooking stoves
Cc: Philip Reich; normp741 at aol.com; Keith Schlessinger; David House; Jiddu Broersma; Marc-Antoine Pare; Jiddu Broersma; Crispin Pembert-Pigott
Subject: Re: [Stoves] Examples of results of simmer efficiency Re: [Ethos] Additional presentations at ETHOS 2015

 

Dear Stovers,

 

Not sure what has caused time to skip beat here.  I just wrote and lost a very clever response to the present thread of discussion on the multiple short comings of the WBT which remarked the following: 

 

(1.)  Science - even stove science - grows by fits and starts;

 

(2.)  science learns more from recognizing that big mistakes have inadvertently been made that it does from research that confirms well established scientific paradigms (see Karl Popper’s Logic of Scientific Discovery for the usefulness of scientific failure)

 

(3.)  in science - even the science of biomass stoves - progress comes from the

retransmission of falsehood (falsification) by deductive chains of logic from the failed predictions back to the falsification of theories, metrics, and models because they generated mistaken predictions about stove performance (or such matters as planetary motion, climate warming and weirding, the effect of GMO 's on human and animal health, race as a construct and its effect on IQ, and the Lamarkian notion that acquired characteristics can be inherited, etc.)

 

(4.)  we are fortunate that people like Ianto Evans, Larry Winiarski, Dean Still, Peter Scott, Nordica, Sam, and probably many others I do not know took the bull by the horns and bravely originated a preliminary set of principles for designing improved biomass burning stoves and also cobbled together a series of provisional efficiency and emission tests. 

 

These were the original Aprovecho stove pioneers who also founded the Rocket Stove movement which mercifully improved upon the earlier Lorena stove experiment that constructed thousands of high mass clay/sand ‘masonry’ stoves which were soon discovered to be much less efficient than a well operated 3 stone fire. This group of appropriate technology oriented, back to the land hippies gradually became more technical and began to refine and apply the VITA WBT to measure and compare the efficiency of different kinds of simple biomass stoves. 

 

They put together a set of specifications and principles for designing, building and optimizing the Rocket Stove which became the prototype in the mind of the Aprovecho movement for all improved cookstoves anywhere in the world.  

 

Finally, the Aprovecho-niks and communards were joined by university based engineers, physicists, chemists, and atmospheric scientists from UC Berkeley, and a wide spectrum of university based scientists and private sector professionals associated with the annual Ethos conference. 

 

This professional and hands on US based network has been busy over the past 15 years attempting to clearly specify metrics that measure the technological performance of biomass stoves. It has also pioneered the design and instrumentation of stove testing centers and the specification of observational protocols that correctly ‘opertionalize’ these metrics.  From the beginning, the main purpose was to discover simple tests that empirically assess the efficiency and emission performance of improved biomass stoves and also to make quantitative comparisons between improved stoves. 

 

The rejection or lukewarm reception of many – perhaps most - improved stoves in many countries of the developing world over the years has forced European, American, Indian, African, Latin American, and Chinese designers and makers of improved stoves to gradually expand their horizons to investigate the roles played by all the other major factors, interests, and constituencies which significantly influence over the acceptance or rejection of new biomass stoves including: (i.) funding agents like USAID, the World Bank, and GIZ, (ii.) standard setting agencies like EPA and the WHO, (iii.) large scale industrial and village scale craft manufacturers, (iv.) the controllers of access to gathered or commercialized fuels from the nearby environments, and (v.) the socio-economic, cultural, and human factors involved in the institutionalization of  one or more dominant stove technologies and products in a particular market segment; these human factors are ultimately the most important determinants of user acceptance or rejection of improved stoves. The acceptance or rejection depends on the perceptions of the utility of a new stove within the household economy where the stove has multiple functions to perform: cooking the food eaten by the family, heating its home, earning income by providing heat to power home industry, purifying water, drying crops, providing light, and creating a social and spiritual center around which family life revolves.  

 

Speaking as a science challenged social anthropologist I think that several things need to be acknowledged about the Aprovecho/Berkeley/Ethos (ABE) alliance. 

 

(1.)  It has done a good job of promoting the Rocket Stove design around the world. 

(2.)  On the down side, its efforts to demystify the design of improved stoves and empower village and craft fabricators of simple low cost stoves, the ABE Alliance appears to have conflated improved stoves in general with the basic Rocket Stove. 

(3.)  This conflation of Rocket stoves with biomass stoves in general has unfortunately led to emission and efficiency metrics and testing procedures which perhaps unintentionally advantage the Rocket Stove and disadvantage all other types of stoves (e.g., the specification of 1 inch square pieces of oven dried spruce or pine as the test fuel that must be expertly fed into any stove being tested).  The reliance on metrics and test protocols which favour some stoves and disadvantage other stoves does not lead to stable or valid comparisons of the efficiency and emission performances of different types of stoves or even the same kind of stoves. 

(4.)  The leadership role assumed by the Aprovecho/Berkeley/Ethos Alliance in the US State Dept funded and EPA supported Global Alliance for Clean Cookstoves and the GACC’s adoption of the WBT metrics, protocols and instrumentation has complicated an already complex predicament. Because personal and institutional reputations are at risk, it is becoming increasingly difficult to radically change the WBT metrics, test protocols, and instruments without creating winners and losers. The GACC and big political players are in danger of exposure for prematurely funding big implementation programs without first settling the science of small biomass stove testing. 

(5.)  Here is my proposal for salvaging the present ugly situation of stove scientists behaving badly in public: let all the stove scientists and stove testers who think they know how to test the efficiency and emissions of small cooking and heating stoves agree on an independent standard developing and setting organization like TUV Rheinland-USA (www. <http://www.tuv.com/en/usa/home.jsp> tuv.com/en/usa/home.jsp)  or some other respected science testing establishment in the world and ask them to review all the different metrics, testing protocols, equipment/instrumentation on offer.  The GACC probably has the funds needed to pay for such a comprehensive review. It can invite all the stove scientists and testers with skin in the game to form themselves into a small advisory body whose job is to ensure that no interested party or parties captures or dominates the review of existing test protocols and metrics. That means the proposed advisory group will have to consult openly about the rules that will govern the consultative, re-conciliatory and global culture and science creating process they will go through together.  

(6.)  I understand that the ISO process and the IWA’s are attempting to do what I am proposing we ask TUV Rheinland or another comparable science testing institution to do on behalf of the presently dysfunctional small stove community around the planet. Here is my contention: the ISO was and is premature because the small stove community is too divided by conflicting research styles and programs prioritizing the stove operator, family health, employment creation, environmental stability, energy sustainability, and decentralization and appropriate technology.  The suggested involvement of TUV Rheinland USA is to help a grumpy, preoccupied, and stressed out international stove community to speed up its integration around second generation metrics, stove testing protocols, lab procedures, and possibly even field tests. 

 

My interest here is to allow all stove scientists and hands-on stove innovators to give their testimony about: 

 

(i.)            what specific aspects of stove performance need to be observed, reduced to metrics,  quantified and compared, 

(ii.)           what testing protocols, methodologies, equipment, and 

(iii.)          what field observations are required to predict both stove performance and probable  stove use in particular target communities? 

 

In that way the Independent third party agency reviewing the WBT, the testimony of the partisans of particular approaches to testing and specific metrics, will get the benefit of all the years of good work done by stove scientists, manufacturers, trainers, vendors, lab testers, back yard innovators, etc. around the world. 

 

If we simply continue the low intensity stove testing wars fought at the World Bank, USAID, EPA, UC Berkeley, several national labs, the GACC, and in most of the different countries where stove testing is under development we will continue to develop backwards. It is not fair to our partners in the developing world because we are sewing confusion and conflict among our partisans and our enemies. My goodness such conduct is not professional, even in post modern North America and Europe where nowadays it’s difficult to find a flesh and blood human being to talk to in the midst of cyber anarchy and inward facing crowds.

 

And let us not forget dear Rumi, a Sufi poet who wrote in the 13th century:    

 

Out beyond ideas of wrong doing and right doing,
there is a field. I'll meet you there.

When the soul lies down in that grass,
the world is too full to talk about.
Ideas, language, even the phrase "each other" doesn't make any sense.

 

Ask Rumi to help us find our way out of this mess we are creating. And do not forget what Walt Kelly’s philosophical opossum - Pogo - who lived in the Okefenokee swamp in my part of south Georgia as known to say when politics got out of hand:

 

“We have met the enemy and he is us” or even better: “we are defeated by insurmountable opportunities”. 

 

In search and service,

CECook 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dear Stovers,

 

Not sure what has caused time to skip a beat here.  I just wrote and lost a very clever response to the present thread of discussion on the multiple short comings of the WBT which remarked the following: 

 

(1.)  Science - even stove science - grows by fits and starts;

 

(2.)  science learns more from recognizing that big mistakes have inadvertently been made that it does from research that confirms well established scientific paradigms (see Karl Popper’s Logic of Scientific Discovery for the usefulness of scientific failure)

 

(3.)  in science - even the science of biomass stoves - progress comes from the 

retransmission of falsehood (falsification) by deductive chains of logic from the failed predictions back to the falsification of theories, metrics, and models because they generated mistaken predictions about stove performance (or such matters as planetary motion, climate warming and weirding, the effect of GMO 's on human and animal health, race as a construct and its effect on IQ, and the Lamarkian notion that acquired characteristics can be inherited, etc.)

 

(4.)  we are fortunate that people like Ianto Evans, Larry Winiarski, Dean Still, Peter Scott, Nordica, Sam, and probably many others I do not know took the bull by the horns and bravely originated a preliminary set of principles for designing improved biomass burning stoves and also cobbled together a series of provisional efficiency and emission tests. 

 

These were the original Aprovecho stove pioneers who also founded the Rocket Stove movement which mercifully improved upon the earlier Lorena stove experiment that constructed thousands of high mass clay/sand ‘masonry’ stoves which were soon discovered to be much less efficient than a well operated 3 stone fire. This group of appropriate technology oriented, back to the land hippies gradually became more technical and began to refine and apply the VITA WBT to measure and compare the efficiency of different kinds of simple biomass stoves. 

 

They put together a set of specifications and principles for designing, building and optimizing the Rocket Stove which became the prototype in the mind of the Aprovecho movement for all improved cookstoves anywhere in the world.  

 

Finally, the Aprovecho-niks and communards were joined by university based engineers, physicists, chemists, and atmospheric scientists from UC Berkeley, and a wide spectrum of university based scientists and private sector professionals associated with the annual Ethos conference. 

 

This professional and hands on US based network has been busy over the past 15 years attempting to clearly specify metrics that measure the technological performance of biomass stoves. It has also pioneered the design and instrumentation of stove testing centers and the specification of observational protocols that correctly ‘opertionalize’ these metrics.  From the beginning, the main purpose was to discover simple tests that empirically assess the efficiency and emission performance of improved biomass stoves and also to make quantitative comparisons between improved stoves. 

 

The rejection or lukewarm reception of many – perhaps most - improved stoves in many countries of the developing world over the years has forced European, American, Indian, African, Latin American, and Chinese designers and makers of improved stoves to gradually expand their horizons to investigate the roles played by all the other major factors, interests, and constituencies which significantly influence over the acceptance or rejection of new biomass stoves including: (i.) funding agents like USAID, the World Bank, and GIZ, (ii.) standard setting agencies like EPA and the WHO, (iii.) large scale industrial and village scale craft manufacturers, (iv.) the controllers of access to gathered or commercialized fuels from the nearby environments, and (v.) the socio-economic, cultural, and human factors involved in the institutionalization of  one or more dominant stove technologies and products in a particular market segment; these human factors are ultimately the most important determinants of user acceptance or rejection of improved stoves. The acceptance or rejection depends on the perceptions of the utility of a new stove within the household economy where the stove has multiple functions to perform: cooking the food eaten by the family, heating its home, earning income by providing heat to power home industry, purifying water, drying crops, providing light, and creating a social and spiritual center around which family life revolves.  

 

Speaking as a science challenged social anthropologist I think that several things need to be acknowledged about the Aprovecho/Berkeley/Ethos (ABE) alliance. 

 

(1.)  It has done a good job of promoting the Rocket Stove design around the world. 

(2.)  On the down side, its efforts to demystify the design of improved stoves and empower village and craft fabricators of simple low cost stoves, the ABE Alliance appears to have conflated improved stoves in general with the basic Rocket Stove. 

(3.)  This conflation of Rocket stoves with biomass stoves in general has unfortunately led to emission and efficiency metrics and testing procedures which perhaps unintentionally advantage the Rocket Stove and disadvantage all other types of stoves (e.g., the specification of 1 inch square pieces of oven dried spruce or pine as the test fuel that must be expertly fed into any stove being tested).  The reliance on metrics and test protocols which favour some stoves and disadvantage other stoves does not lead to stable or valid comparisons of the efficiency and emission performances of different types of stoves or even the same kind of stoves. 

(4.)  The leadership role assumed by the Aprovecho/Berkeley/Ethos Alliance in the US State Dept funded and EPA supported Global Alliance for Clean Cookstoves and the GACC’s adoption of the WBT metrics, protocols and instrumentation has complicated an already complex predicament. Because personal and institutional reputations are at risk, it is becoming increasingly difficult to radically change the WBT metrics, test protocols, and instruments without creating winners and losers. The GACC and big political players are in danger of exposure for prematurely funding big implementation programs without first settling the science of small biomass stove testing. 

(5.)  Here is my proposal for salvaging the present ugly situation of stove scientists behaving badly in public: let all the stove scientists and stove testers who think they know how to test the efficiency and emissions of small cooking and heating stoves agree on an independent standard developing and setting organization like TUV Rheinland-USA (www. <http://www.tuv.com/en/usa/home.jsp> tuv.com/en/usa/home.jsp)  or some other respected science testing establishment in the world and ask them to review all the different metrics, testing protocols, equipment/instrumentation on offer.  The GSCC probably has the funds needed to pay for such a comprehensive review. It can invite all the stove scientists and testers with skin in the game to form themselves into a small advisory body whose job is to ensure that no interested party or parties captures or dominates the review of existing test protocols and metrics. That means the proposed advisory group will have to consult openly about the rules that will govern the consultative, reconciliatory and global culture and science creating process they will go through together.  

(6.)  I understand that the ISO process and the IWA’s are attempting to do what I am proposing we ask TUV Rheinland or another comparable science testing institution to do on behalf of the presently dysfunctional small stove community around the planet. Here is my contention: the ISO was and is premature because the small stove community is too divided by conflicting research styles and programs prioritizing health, employment creation, environmental stability, energy sustainability, decentralization and appropriate technology.  The suggested involvement to TUV Rheinland USA is to help a grumpy, preoccupied, and stressed out international stove community to speed up its integration around second generation metrics, stove testing protocols, lab procedures, and possibly even field tests. 

 

My interest here is to allow all stove scientists and hands on stove workers to give their testimony about 

 

(i.)            what specific aspects of stove performance need to be observed, reduced to metrics, quantified and compared, 

(ii.)           what testing protocols, methodologies, equipment, and 

(iii.)          what field observations are required to predict both stove performance and probable stove use in particular target communities? 

 

In that way the Independent third party agency reviewing the WBT, the testimony of the partisans of particular approaches to testing and particular metrics, will get the benefit of all the years of good work done by stove scientists, manufacturers, trainers, vendors, lab testers, back yard innovators, etc. 

 

If we simply continue the low intensity stove testing wars fought at the World Bank, USAID, EPA, UC Berkeley, several national labs, the GACC, and in most of the different countries where stove testing is under development we will continue to develop backwards. It is not fair to our partners in the developing world because we are sewing confusion and conflict among our partisans and our enemies.

 

And let us not forget dear Rumi, a Sufi poet who wrote in the 13th century:    

 

Out beyond ideas of wrongdoing and right doing,
there is a field. I'll meet you there.

When the soul lies down in that grass,
the world is too full to talk about.
Ideas, language, even the phrase "each other" doesn't make any sense.

 

Ask Rumi to help us find our way out of this mess we are creating. And do not forget what Walt Kelly’s philosophical opossum of the Okefenokee swamp in my part of south Georgia liked to say:

 

“We have met the enemy and he is us” or even better: “we are defeated by insurmountable opportunities”. 

 

In search and service,

CECook 

 

 

On Sun, Feb 15, 2015 at 1:35 PM, Dean Still <deankstill at gmail.com> wrote:

Dear Philip,

 

The Low Power test works well when the fuel use is normalized using a set simmering temperature. 

 

Sam and I are writing up some characteristics of the WBT and I'll post the paper here. Lots of work to do and I look forward to our continued collaboration.

 

Best,

 

Dean

 

On Sun, Feb 15, 2015 at 11:43 AM, Philip Lloyd <plloyd at mweb.co.za> wrote:

Dear Dean

 

Crispin said it well:
“The three low power metrics are invalid. The variables selected are inappropriately chosen. The calculated results are misleading and contrary to any claim [that] they provide guidance for product development or selection. We have to move on.” 

 

I have looked at the simmering metrics in WBT 4.3.2 and can only concur.  That is why I do not think we should waste much more time arguing about them – they are fundamentally wrong. Yes, stove designers need to be concerned with simmering and turndown; no, the WBT simmering metrics do not provide them with guidance, and can be positively misleading, which is worse.

 

Kind regards

 

Philip Lloyd

 

 

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Dean Still
Sent: 15 February 2015 06:38
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] Examples of results of simmer efficiency Re: [Ethos] Additional presentations at ETHOS 2015

 

Dear Prof Loyd,

 

As I pointed out, when the stoves do the same work (hold the water at 97 C, for example) the stove with greater heat transfer efficiency scores better. Simmering tests are important and simmering is an important part of cooking.

 

The ISO process is creating new history and approaches to old problems. Whatever emerges will certainly be defensible as the new approaches are forged by consensus.

 

Best,

 

Dean

 

On Sun, Feb 15, 2015 at 12:58 AM, Philip Lloyd <plloyd at mweb.co.za> wrote:

I am concerned that this is turning into a very fruitless discussion.

 

On fundamental grounds the simmering test does not provide anything meaningful.  Crispin has demonstrated that rigorously, and others have pointed out that the test can score an efficient stove poorly and an inefficient stove well, so it does not provide any useful measure.  To go on defending the indefensible does not make sense, even if it did accentuate the need for turndown – but that need was always there, it was not the product of the WBT.

 

We need defensible measures of stove performance.  Can we please turn our attention to developing those, and leave the indefensible to history?

 

Prof Philip Lloyd

Energy Institute

Cape Peninsula University of Technology

PO Box 652, Cape Town 8000

Tel:021 460 4216

Fax:021 460 3828 <tel:021%20460%203828> 

Cell: 083 441 5247 <tel:083%20441%205247> 

 

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Paul Anderson
Sent: 15 February 2015 02:26
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] Examples of results of simmer efficiency Re: [Ethos] Additional presentations at ETHOS 2015

 

Dear Dean,    my reply is below:

Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD  
Email:  psanders at ilstu.edu   
Skype: paultlud      Phone: +1-309-452-7072 <tel:%2B1-309-452-7072> 
Website:  www.drtlud.com

On 2/14/2015 1:06 PM, Dean Still wrote:

Dear Paul, 

 

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.

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.

 

Specific Consumption is based on how much energy was used to create simmered water. 

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.   

If the stove only operates at high power there is more steam made and [at the end of testing] less simmered water remains....

that is true.   but continue.

..... so energy was used to create less product.

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.)

 

I like Specific Consumption because it forces stove designers to make stoves that simmer successfully, not just boil water. 

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.

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.

The cause-and-effect relationship is not totally clear.   We have wanted turn-down capabilities in TLUDs for many years.   

 

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. 

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." 

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. 

 

Sam is doing great work as he crunches all the data....

absolutely.   But we are questioning if the numbers are as valid and useful as claimed.

 and gives ISO real numbers to work with in their discussions.


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.   

Paul



 

Best,

 

Dean

 

On Sat, Feb 14, 2015 at 8:18 AM, Paul Anderson <psanders at ilstu.edu> wrote:

Dear Tom H.,         and to all who are interested in proper testing of stoves.

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.

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.

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.  

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".   

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, IF found to be faulty.   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.

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.

Paul 

Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD  
Email:  psanders at ilstu.edu   
Skype: paultlud      Phone: +1-309-452-7072 <tel:%2B1-309-452-7072> 
Website:  www.drtlud.com

 

 


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