[Stoves] ND-TLUD Burners at ETHOS -- What Works Best?

Fri Feb 5 10:13:32 CST 2016

Nobert,

The focus at ETHOS was almost entirely on fan driven rockets or TLUD’s to reach T4 criteria. T4 stoves to the developing world are like the space shuttle is to the average person: the spin offs from the development process are probably useful but we’ll never have a chance to fly one. 

We had a great time but how can we get more useful value from the gathering? Out of 28 million stoves it would be useful to know statistics about what kinds of stoves are actually used, where, by whom, what fuels, stove life, costs, etc. Fan driven, solar powered TLUD’s are fun but where are they being used?

At the end of the conference we wondered why organizations like Trees Water People and Helps were not at the conference. How can the conference help organizations like InStove, StoveTeam, Stovetec, Lifeline, AidAfrica, Obama, Helps, Trees Water and People, in country projects and producers, and others improve and sell their stoves? How do the extensive surveys and advanced modelling help these organizations that are on the ground?  We could use a lot more discussion about mundane topics like how to extend the life or replace components in simpler designs that sell, how to make efficient designs more acceptable, etc.     

Tom

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Nolbert Muhumuza
Sent: Thursday, February 04, 2016 10:12 PM
To: Stoves <stoves at lists.bioenergylists.org>
Cc: Julien Winter <winter.julien at gmail.com>; Tom Starrs <tomstarrs at b-e-f.org>
Subject: Re: [Stoves] ND-TLUD Burners at ETHOS -- What Works Best?

Thank you all for the feeds and updates from this year's ETHOS conference.

It feels like we are on the right path with TLUD stoves.

What is the progress/ updates on usage/ acceptance e.g. in coverage/ distribution Vs other types of ICS?

Any financing with focus to TLUD projects in the foreseeable future? 

Nolbert.

On 5 Feb 2016 07:27, "Ronal W. Larson" <rongretlarson at comcast.net <mailto:rongretlarson at comcast.net> > wrote:

Julien, List, Tom:   (This also to be considered the last of the ETHOS series.)

Thanks Tom.  I’m writing on flight home from Aprovecho, so will take a first crack at this  (giving credit to Kirk Harris who drove me to Eugene and we discussed this a bit).  I hope others will jump in.

1.  My view is that we have not had any real “breakthroughs” in the stove world - but are making good progress.   If we likened our path to going to school - the stove world is perhaps in middle school - lots still to learn in High School and College ahead of us.  In this I am restricting myself to your interest (and most short-termers at Apro) - in TLUDs.  I see little new information likely to occur with charcoal-using stoves and Rockets (they are mature technologies).  At Apro, ALL the testing (and advance?) was with TLUDs this time;  no charcoal-using stoves or Rockets  (but plenty around to look at).

2.  I think more than half of the testing was with fans, including the previously mentioned Mimi-Moto (testing mostly by Paul Anderson.  But also testing with TLUD fan - stoves made in Portugal (excellent high quality factory workmanship), Ohio (very large, using rice husks), and one set from South Africa.   The first three and most fan stoves that I have seen have fans in the stove itself.  The one from South Africa (developed by Dave Lello) is the first I recall having the fan in a fixed base.  More important to future sales is that the fan electrical supply is a small addition (20-25%) of the solar panel coming with the stove - also supplying lighting and cell-phone recharging.  Considerable discussion with Dave about marketing using PAYGo principles (users can see money saved from day 1).

3.  This last (“Lello”) stove was being tested with the normal (outer) secondary air hole locations, but also an alternative using an interior “column”.  This could be a wave of the future - because of the way this prevents the normal (too-laminar) central flame.  Good results (meaning low emissions, constant power, etc) were being obtained in the first testing over these last three days.

4.  Several times at ETHOS we heard that the optimum ratio of primary air to secondary air was about .25 to .3  (or primary to total about 0.2 to .25).  [for emphasis -  secondary to primary at 3.5 to 4.)  Perhaps we should be thinking of controlling the larger (secondary) amount - and bleeding a little off for the primary.  I don’t know of anyone who is thinking or doing that.

5.  With the real-time testing equipment available at Apro, it is possible to see “strange” events that we don’t see in normal operation.  Kirk Harris saw at least three still-unexplained happenings.  The CO level rose significantly in the early stages - a broad peak at first when first lit - maybe 10 times as high as during normal operation.  Perhaps due to the pyrolysis front not really having been established.  But then, after a good strong flame had been established, a very similar “bump” occurred as the 5 liter pot of water was added.  Reduced air flow?  Different radiation conditions?

CO is not considered a major problem - except in charcoal-using stoves.

6.  Kirk for the first time today noted that near the end of the run, the particulate count went below the ambient.  The stove was cleaning up the room air.  Why?

7.  “Big” spikes for both CO and particulates - often (usually) appear as the pyrolysis front reaches the bottom.  - But not always. Why?

8.   Every morning at Apro, there is a handout of all the previous day’s testing results.  Kirk noted that this year there were many more Tier 4 levels than he recalls from past testing. 

7.  Kirk was testing for the first time a ‘radiant-fin-array-dome”.  As the gases exit the stove - this “dome” turns red and presumably helps in radiant heat transfer to the pot.  More to come from Kirk on that.  Dean Still reported at ETHOS the use of a special exhaust cleanup catalyst material - that turns white and should similar help with radiant heat transfer.

8.  Some discussion on using the pot to limit airflow - for improving heat transfer.  We saw no aperture changes (o control power levels) during operation but this might be a future control mechanism.  Arnold Oliphant demonstrated 1 and 2 mm flame-exit gaps.

9.  I saw some excellent looking new experimental and analytic material at ETHOS - mostly on TLUDs.  We will have to wait to receive the PPts to better understand if these were breakthroughs.  I saw several PPts that might be small breakthroughs.

10.  Lots of discussion of fuels.  There seems sure to be increased emphasis on pellets.

11.  I heard the word “biochar” more than previously.  More than “carbon negativity”; emphasis on soils, although the benefits are not in conflict.

Ron

On Feb 4, 2016, at 9:12 AM, Tom Miles <tmiles at trmiles.com <mailto:tmiles at trmiles.com> > wrote:

Julien,

Great question for the group that is at Aprovecho this week including Paul, Krista, Ron and others. I’m sure that they are still busy testing.

Tom 

From: Stoves [ <mailto:stoves-bounces at lists.bioenergylists.org> mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Julien Winter
Sent: Wednesday, February 03, 2016 9:02 PM
To: Discussion of biomass cooking stoves < <mailto:stoves at lists.bioenergylists.org> stoves at lists.bioenergylists.org>
Subject: [Stoves] ND-TLUD Burners at ETHOS -- What Works Best?

Hello folks who attended ETHOS

Were any important breakthroughs in natural draft, TLUD gas burners reported at ETHOS?  Is there a concensus developing on what works best?  

I would not be surprised if there is a different solution for pellet fuels as opposed to chunks of wood or large briquettes.  

Cheers,

Julien

-- 

Julien Winter
Cobourg, ON, CANADA

_______________________________________________
Stoves mailing list

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

_______________________________________________
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/20160205/84408e9b/attachment.html>