[Stoves] ETHOS 2013: Where is the New Data on Stove

rongretlarson at comcast.net rongretlarson at comcast.net
Thu Nov 29 20:25:12 CST 2012





Kevin and list: 

I think you are very close to getting what I am saying. I will next reply to Crispin - and so leave some of a full response below to my responses there. 

Some of this also relates to comments made today by Jim Jetter in response to Crispin - which message I hope all will look at carefully.. 

A few responses below. Not needing a response to #1. 

----- Original Message -----
From: "Kevin" <kchisholm at ca.inter.net> 
To: "Discussion of biomass cooking stoves" <stoves at lists.bioenergylists.org> 
Sent: Wednesday, November 28, 2012 10:27:40 PM 
Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove 


Dear Ron 

I missed what you are trying to accomplish, but I offer the following: 

1: C+O2 ---> CO2 tell us that 1 gram of C is equivalent to 44/12 = 3.66 gms CO2. Your 3.7 factor below is correct. 

2: Any stove burning any biomass sourced fuel is inherently "Carbon Neutral", at the very least, in that no new C is added to the Biosphere. 
[RWL2: As Crispin noted, one can inappropriately use some biomass. So, I would not use the word "any". This is a main point of dialog in current EPA deliberations about bioenergy. I am comfortable with cutting forests in the US if overall US biomass growth exceeds cutting. But mostly I think we will see dedicated areas of species like switch grass and miscanthus - so the CO2 payback time can be measured in months, not decades. To repeat, n ot every biomass fuel should be eligible for carbon credits.] 


3: The case where 100% of the C in the fuel (biomass or char) is burned to CO2 would result in a "Carbon Neutral" stove. This condition has the potential for giving a stove with maximum efficiency, in the "Class 1" context... least fuel requirement to "get the job done." There is no carbon sequestration. There is no carbon negativity. 
[RWL3a: OK. But not all CO2 produced in the "Class 1" stove should be eligible for carbon credits. Stoves receiving a credit up front should also have to make some guarantees on char lifetime. etc. ] 


3: A stove that burns part of the C in a biomass sourced fuel is inherently "Carbon Negative" in that a portion of the C in the fuel is removed from the biosphere as char, either unintentionally (as "carbon loss" to the ash) or intentionally (when operated to produce biochar.) 
[RWL3b: OK - but I prefer to use the word "pyrolyzes" in place of "burns". It should be very rare that any recoverable char is thought of as a "loss". Any char is more valuable placed in soil than anywhere else (although maybe should fi rst provide other non-soil benefits) . 



(For the sake of simplicity in the example below, I assume that wood is 50% Carbon, and that biochar recovery is 20% of weight of the dry wood feed to a TLUD stove You can pick whatever numbers you feel are appropriate and re-do the calculations.) 
[RWL 3c : The point of my note was that these numbers (and more below) should be a featured output of char-producing stove testing. No need to assume anything (and I recognize you a re only giving an example .] 


4: For a stove producing char intentionally, 40% of the C in the incoming fuel is unburned, and is thus available for use as biochar. Additionally, the 40% of the "Incoming Carbon" can be considered as a "carbon negative benefit", in that this is C that can be removed from the Biosphere. The 60% of the carbon that was burned yields "Carbon Neutral Carbon", in that it came from the atmosphere and combustion simply returns it to the atmosphere. 
[RWL4 a : I would replace "C that can be removed from the Biosphere" with "excess C that is transferr ed from the A tmosphere to the Biosphere - with continuing out year benefits (in both categories) if properly produced and placed " ] 


Is this helpful in getting you closer to what you want to accomplish? Can you perhaps re-state what you want to accomplish? 
[RWL4b: Yes to 1s t Q - much; thanks. I am trying to get the water boiling test literature to add information related to C and CO2 - especially for char-making stoves. I haven't yet said so in this sequence, but hope to later have comments also showing that biochar can only be properly analyzed economically by including out-year benefits - some of which involve other gases such as N2O, CH4. That is down the road. 

Ron] 


Best wishes, 

Kevin 


----- Original Message ----- 
From: Ron 
To: Discussion of biomass cooking stoves 
Cc: Ranyee Chiang ; Discussion of biomass cooking stoves 
Sent: Wednesday, November 28, 2012 11:21 PM 
Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove 



Kevin 


You ask if your suggestion would simplify things. The answer is yes. But it wouldn't help at all in what I am trying to do. My message used the term "CO2" repeatedly. Yours does not. 


Every stove making char for CO2 reasons had better also do a good job cooking - including emissions. I am asking for no new tests. Only a new computation that is based on CO 2. 


Ron 



On Nov 28, 2012, at 1:01 PM, "Kevin" < kchisholm at ca.inter.net > wrote: 



<blockquote>


Dear Ron 

May I suggest for your consideration that there be two distinct categories of stoves: 
1: Stoves whose intended purpose is cooking and heating. (Cooking and Heating Stoves) 
and 
2: Stoves whose purpose is "Climate Change Improvement." (Climate Change Stoves) 

Cooking and Heating stoves would have their efficiency rated on the degree to which "incoming" fuel energy was used to get the job done. Any char appearing in the ash would be a dead loss, as far as stove efficiency was concerned. 

On the other hand, Climate Change Stoves would have their efficiency rated on the difference between the energy content of the incoming fuel and the energy content of the recovered char. 

Relevant Testing Protocols could be developed for stoves intended for either use. However, a given stove could be tested for both applications. 

Wouldn't that simplify things? 

Best wishes, 

Kevin 



<blockquote>

----- Original Message ----- 
From: rongretlarson at comcast.net 
To: Discussion of biomass cooking stoves ; Ranyee Chiang 
Sent: Wednesday, November 28, 2012 3:11 PM 
Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove 




Ranyee and list: 

Thank you for Monday's GACC response (below) to Tom. Yours gives me a chance to urge a relatively small addition to the 4.1.2 water boiling test we have recently discussed on this list and to which I think you were responding. My requested addition is to use already-collected data to also supply a new stove measure that will help those (like myself) who believe stoves can play a major role in getting both to zero fossil fuel use and also to 350 (or lower) ppm CO2. This suggestion is solely built around the term "CO2" - which I don't see enough of in the GACC web pages. 

To do this, I want to provide/emphasize the percent of the initial fuel's carbon that ended up as a recalcitrant char for placement in soil (only then called biochar). All of the data needed to do this are already being considered, but the ratio (a number near 40-50%) is nowhere provided. Giving only the weight of the char is insufficient (a ratio near 20-25%). This requested value can be given either in C or CO2 terms (those dealing with geoengineering costs prefer C, but carbon prices are almost universally given in CO2 (or CO2-eq) terms). I think providing both variations will be helpful - especially to emphasize the differences when costs enter the dialog. That is, a price of $10/tonne CO2 is the same as $37/tonne C (and we need both to be higher if we are interested n 350 ppm CO2). Too often, I see the terms confused. 

The present GACC handling of char weight is to compute its energy content and subtract this from the input biomass energy in the denominator of an energy efficiency computation. This bothers some on this list, but I think is relatively OK if the char is eventually productively used. But if one wants to really understand how well the rest of the biomass was used that did not go into char production, then one should simply divide the saved fossil energy's C or CO2 by the similar quantity in the input biomass. It is NOT appropriate to say that all of the CO2 produced in the WBT was carbon neutral. And different fossil fuels would have different CO2 outputs; the displacement of methane would displace about half as much CO2 as would displacement of coal. 

This complexity of the displaced fuel is not highlighted in the GACC material. It is an unfortunate complexity related to the percent hydrogen in the different fuels (including charcoal seen as a fuel). Nevertheless, for those interested in global warming, I suggest that this additional set of data provided by the GACC WBT's will help clarify why many of us on the stove list are interested in stove technologies (I was the first stove list coordinator - always emphasizing how bad charcoal burning is). Additional GACC data will emphasize the importance of both carbon neutrality and carbon negativity in the stove world. I do not see sufficient recognition of this duality in the present GACC material. The source of the char should be emphasized when you report on the efficiency of jikos. 

I recognize that I have only given a broad brush description. I will work with the small amount of charcoal-related data in EPA's (Jim Jetter's) approach and any in the Berkeley data (which I have requested, but do not yet have from your office). It is very unfortunate that there is still so little data to work with for char-making stoves (too much in the "grey" literature). If anyone can supply me with such data, I will calculate the new CO2 data I am looking for. What I think we will find is that char-making stoves have quite high efficiencies - in the range 80 to 90 % - roughly 40-45% each for the carbon neutral and carbon negative portions. This does not now come across in any GACC material I now read. We absolutely need two efficiency numbers we can add together - and I do not now see them. 

To repeat the essence of the above - CO2 is the only parameter I have found which can be used to analyze carbon neutrality and negativity together. Weight and energy units do not tell the CO2 story. An emphasis on energy alone is fine if you are not interested in CO2-induced global warming. But the production of biochar is necessarily accompanied by a reduction in energy. Biochar enthusiasts recognize that we can't have both high energy output and high char output. But both are now important. Having CO2 (or C) appear in the numerators of the separate carbon neutral and carbon negative terms seems to be a mathematical necessity. Having the energy content of char appear only in the denominator of an energy efficiency computation means that the whole story of char-making stoves is not being told. 

I welcome further dialog on this topic. 

Ron 


----- Original Message -----
From: "Ranyee Chiang" < rchiang at cleancookstoves.org > 
To: stoves at lists.bioenergylists.org 
Sent: Monday, November 26, 2012 11:48:05 AM 
Subject: [Stoves] ETHOS 2013: Where is the New Data on Stove 




Dear Tom and all, 



I wanted to jump into this conversation to emphasize that providing access to data on stove performance in the field is high on the priority list for the Global Alliance for Clean Cookstoves. 



The recently released Stove Performance Inventory has already been mentioned, which was an effort to pull together existing publically available data for laboratory and field testing. We will be having a webinar on December 11 4 pm GMT, which will cover the development of the inventory, results, an overview of the existing format for the Inventory, and discussion of next steps (keeping the inventory up to date, improving the accessibility and query-ability of the interface, etc). 



All projects selected through the external peer review process and funded by the Global Alliance (published online when the grants are finalized) are required to make their data publically available. The most relevant field studies came out of a recent Request for Applications , and these projects are currently getting started now. The information about these studies is getting posted online as we speak, since these grants were only recently finalized. And as these projects and other recently funded projects progress, that work and the resulting data will be shared. 



A comment was also made about committees related to standards and testing. We are working extremely hard to make discussions and meetings inclusive and widely attended. We will continue to use channels like this listserv to keep everyone updated about upcoming activities (online, teleconference, and in person), and we will continue to support travel to help people attend meetings in person. I have been posting regular updates on standards and testing activities in the Communities section of the Global Alliance website, and I am happy to talk to anyone interested in more detailed updates. 



Best regards, 

Ranyee 




	

<image001.png> 	

Ranyee Chiang, Ph.D. 

Senior Technical Manager 

rchiang at cleancookstoves.org 

www.cleancookstoves.org 







Date: Mon, 26 Nov 2012 16:06:01 +0000 

From: "Bryden, Kenneth [M E]" < kmbryden at iastate.edu > 

To: Discussion of biomass cooking stoves 

< stoves at lists.bioenergylists.org > 

Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove 

Performance in the Field? 

Message-ID: 

< 75123EB3655A6E44B6FC942F119B90CA0373EF0E at ITSDAG4A.its.iastate.edu > 

Content-Type: text/plain; charset="windows-1252" 



Tom, 



Sounds like a great idea and I'm sure by the flurry of writing this weekend that it would attract a lot of interest. I also know that there are a lot of questions that need be answered. 



Maybe a format that could work would be a panel for the whole group followed by a set of talks for those who wish to continue the discussion. Can you put together a panel and a set of talks that would represent the divergent views on this topic? 



Dean - any thoughts 



Thanks 

Mark 



On Nov 23, 2012, at 10:36 AM, Tom Miles wrote: 



Mark, 



You have listed a number of standards and protocol topics. Now that GACC exists have we made any gains on the science side? Where is the data? We should be generating good field data by now. I don?t want to just hear reports about what people have decided in political committees that nobody seems to be able to attend or vote in. 



I would like to see a critical review of the testing protocols and methods with regard to the key metrics and emissions. For example, the protocols to date have made assumptions about heating values of fuels and residues ash and charcoal that I have always felt were just placeholders until someone with larger research budgets could validate them. Determining the amount of energy left in the ash or charcoal is a good example. I often get asked what value to use for the remaining ash/charcoal. I haven?t seen a test where the remaining charcoal/ash has been directly tested for ash content and heating value. 



Testing the benchmarks. Do the benchmarks that were derived several years ago make sense now that we have improved tools for measuring stove performance or do we get the same numbers because we?re using the same tools? Do the benchmarks tell us anything about stove performance in the field? Do stoves preform in the field in the same relative way they are shown to perform in the lab or are some stoves much better than others (or much worse) when they are used in the field? Are the stoves designed to the test (e.g. WBT) or to the use in the field? Do some stoves perform best when they are tested in the lab and fail in the field? Or, are we even testing for this? 



Field applications. Are our tools and metrics of any use for improving stove performance in actual use? If so then how are projects in developing countries using these tools to improve their fuel use and health? How do local, nation, or regional stove projects use these tools to improve their stoves, or do they just ignore them? 



QA/QC. When a program buys container loads of stoves how do we know that they perform within the expectations created by the test results? Do any of the manufactured stove suppliers test the quality and performance of their stoves on a regular basis? Is there any monitoring? 



How has testing been used for different fuels? I was inspired this week by a photo from Mexican which a construction worker was using an LPG burner in an eCocina stove (Stove Team International) because it substantially reduced his LG use. Can we compare fuel consumption for different fuels? How good are our fuel consumption metrics? 



Health. We still do not have proven direct correlation between stove emissions and heath. Most of the data seems to be recycled. Are there new health studies? Has GACC and the many supporting organizations funded any of the fundamental health studies that every year Jay Smith tells us are lacking? 



These are some of the questions that I would like to see addressed at ETHOS. 



Looking forward to another productive ETHOS. 



Thanks 



Tom 

T R Miles Technical Consultants, Inc. 

tmiles at trmiles.com<mailto:tmiles at trmiles.com > 

www.trmiles.com<http://www.trmiles.com > 

www.stove.bioenergylists.org<http://www.stove.bioenergylists.org > 

















From: ethos-bounces at vrac.iastate.edu<mailto:ethos-bounces at vrac.iastate.edu > [mailto:ethos-bounces at vrac.iastate.edu] On Behalf Of Bryden, Kenneth [M E] 

Sent: Monday, October 22, 2012 2:05 PM 

To: Discussion of biomass cooking stoves; ETHOS - Listserve 

Subject: [Ethos] ETHOS 2013 



All, 



It's that time of year again! We're starting to get the activities together together for the ETHOS conference. The conference will be January 25 - 27, 2013 in Seattle. Proposed discussion topics include 



- Update on the Global Alliance and their activities 

- Standardizing Reporting on IWA Indicators 

- Stove Performance Inventory, Sharing Public Data, and Establishing Common Data Formats 

- Update on ISO Process 

- Updates on Protocol Developments (including possibly charcoal, plancha, batch-fed, durability, finalizing WBT from public comment period) 



Let us know what else you would like to talk about. A lot is happening and I'm sure it will be as exciting as ever. I'd appreciate having your ideas on topics and panels by November 15. 



Abstracts for papers and talks are due January 1. 



For more details, to register, and to submit your abstract the conference web site is http://www.vrac.iastate.edu/ethos/conference.php . 



Please send your ideas directly to Dean and I. 



Best regards 

Mark 

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Message: 6 

Date: Mon, 26 Nov 2012 08:19:46 -0800 

From: "Tom Miles" < tmiles at trmiles.com > 

To: "'Discussion of biomass cooking stoves'" 

< stoves at lists.bioenergylists.org > 

Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove 

Performance in the Field? 

Message-ID: < 00db01cdcbf1$da33d800$8e9b8800$@trmiles.com > 

Content-Type: text/plain; charset="us-ascii" 



Good idea. We can work on it over the next few of weeks. Sorting out the objectives and use of tests, methods and formal protocols would be the place to start. 



Tom 







From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Bryden, Kenneth [M E] 

Sent: Monday, November 26, 2012 8:06 AM 

To: Discussion of biomass cooking stoves 

Subject: Re: [Stoves] ETHOS 2013: Where is the New Data on Stove Performance in the Field? 







Tom, 







Sounds like a great idea and I'm sure by the flurry of writing this weekend that it would attract a lot of interest. I also know that there are a lot of questions that need be answered. 







Maybe a format that could work would be a panel for the whole group followed by a set of talks for those who wish to continue the discussion. Can you put together a panel and a set of talks that would represent the divergent views on this topic? 







Dean - any thoughts 







Thanks 



Mark 







On Nov 23, 2012, at 10:36 AM, Tom Miles wrote: 







Mark, 







You have listed a number of standards and protocol topics. Now that GACC exists have we made any gains on the science side? Where is the data? We should be generating good field data by now. I don't want to just hear reports about what people have decided in political committees that nobody seems to be able to attend or vote in. 







I would like to see a critical review of the testing protocols and methods with regard to the key metrics and emissions. For example, the protocols to date have made assumptions about heating values of fuels and residues ash and charcoal that I have always felt were just placeholders until someone with larger research budgets could validate them. Determining the amount of energy left in the ash or charcoal is a good example. I often get asked what value to use for the remaining ash/charcoal. I haven't seen a test where the remaining charcoal/ash has been directly tested for ash content and heating value. 







Testing the benchmarks. Do the benchmarks that were derived several years ago make sense now that we have improved tools for measuring stove performance or do we get the same numbers because we're using the same tools? Do the benchmarks tell us anything about stove performance in the field? Do stoves preform in the field in the same relative way they are shown to perform in the lab or are some stoves much better than others (or much worse) when they are used in the field? Are the stoves designed to the test (e.g. WBT) or to the use in the field? Do some stoves perform best when they are tested in the lab and fail in the field? Or, are we even testing for this? 







Field applications. Are our tools and metrics of any use for improving stove performance in actual use? If so then how are projects in developing countries using these tools to improve their fuel use and health? How do local, nation, or regional stove projects use these tools to improve their stoves, or do they just ignore them? 







QA/QC. When a program buys container loads of stoves how do we know that they perform within the expectations created by the test results? Do any of the manufactured stove suppliers test the quality and performance of their stoves on a regular basis? Is there any monitoring? 







How has testing been used for different fuels? I was inspired this week by a photo from Mexican which a construction worker was using an LPG burner in an eCocina stove (Stove Team International) because it substantially reduced his LG use. Can we compare fuel consumption for different fuels? How good are our fuel consumption metrics? 







Health. We still do not have proven direct correlation between stove emissions and heath. Most of the data seems to be recycled. Are there new health studies? Has GACC and the many supporting organizations funded any of the fundamental health studies that every year Jay Smith tells us are lacking? 







These are some of the questions that I would like to see addressed at ETHOS. 







Looking forward to another productive ETHOS. 







Thanks 







Tom 



T R Miles Technical Consultants, Inc. 



tmiles at trmiles.com 



www.trmiles.com 



www.stove.bioenergylists.org 



































From: ethos-bounces at vrac.iastate.edu [mailto:ethos-bounces at vrac.iastate.edu] 

On Behalf Of Bryden, Kenneth [M E] 

Sent: Monday, October 22, 2012 2:05 PM 

To: Discussion of biomass cooking stoves; ETHOS - Listserve 

Subject: [Ethos] ETHOS 2013 







All, 







It's that time of year again! We're starting to get the activities together together for the ETHOS conference. The conference will be January 25 - 27, 

2013 in Seattle. Proposed discussion topics include 







- Update on the Global Alliance and their activities 



- Standardizing Reporting on IWA Indicators 



- Stove Performance Inventory, Sharing Public Data, and Establishing Common Data Formats 



- Update on ISO Process 



- Updates on Protocol Developments (including possibly charcoal, plancha, batch-fed, durability, finalizing WBT from public comment period) 







Let us know what else you would like to talk about. A lot is happening and I'm sure it will be as exciting as ever. I'd appreciate having your ideas on topics and panels by November 15. 







Abstracts for papers and talks are due January 1. 







For more details, to register, and to submit your abstract the conference web site is http://www.vrac.iastate.edu/ethos/conference.php . 







Please send your ideas directly to Dean and I. 







Best regards 



Mark 



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