Below is a presentation summarizing the state of fuel in Haiti, as of 2007. All Information is from a study by the Energy Sector Management Assistance Program (ESMAP). Although it is possible that this information is inaccurate because of a significant change after the 2010 earthquake, this comprehensive study is still the most up to date information. The team will be using this information to guide some decisions regarding gathering fuels during our first trip in May. 

Important Points from ESMAP Report 07 on Prezi

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Today we built a TLUD stove using just 3 concrete blocks. Concrete is a common building material in Haiti, so it should be simple to source materials for a stove like this. The addition of a welded rebar pot support (or a few stones) would make this functional as a stove.

Small sticks were used to slightly raise the bottom block off the ground for primary air, and to raise the top block for secondary air. There was also a steel wire mesh grate at the bottom to support the fuel. There was some smoke during startup and at the end of the burn. The flame did not extinguish at the end of pyrolysis, but traveled downward and burned directly on the coals.

Wood pellets are the fuel used in the video.
In the US one block is about $1.60, making this a very low cost option.

Variations

  • Bottom block flat on ground or raised on sticks: both work. Flat on ground is harder to start due to less primary air, but there is enough for a pyrolysis flame.
  • Fuel raised on grate or sitting on the ground: both work. The grate is not necessary, but it does improve the distribution of primary air on the fuel. This was evident at the end of the burn when the perimeter of char was glowing bright while the interior was darker.
  • 4th block, with and without stick spacers: poor results. Sometimes causes too strong of a draft which extinguishes the flame. Additional secondary air doesn't create a second flame. It was hard to start and very smokey.
  • Spacer between bottom and middle block: just moves the secondary air down to the first opening. Thus a stove could be made with 2 blocks.
  • Using the longer, more common concrete brick with 2 sq. holes: poor performance, lot of smoke and difficult to start up, likely because there is more thermal mass to take up heat. I only used 1 side as a stove (not both at once). The corner of the brick cracked off from heat after a single use.

Conclusions

This is an inferior stove to the metal ones we have used previously. It produces much more smoke because it is more difficult to light, and also there is a small to medium amount of smoke that is escaping almost the whole time while the yellow pyrolysis flame is going. This could possibly be fixed if the secondary air could be preheated more, currently it only travels through the wall thickness of the block before we need it to combust. This is evident as smoke is many times visible alongside the pyrolysis flame. 
This stove does transition well from yellow pyrolysis flame to glowing char, without a sudden extinction of the flame and smoke for 1-2 mins as we've seen with several metal TLUD stoves. Thus it is the warm stove body that keeps the weak flame at the end of pyrolysis alive.
I would recommend this only as an upgrade from 3 stone open fire cooking, and only when concrete blocks are available and much less expensive than metal. It does have the advantage of basically requiring zero fabrication and assembly effort: the blocks are bought as-is and stacked, with a stick broken into 4 pieces used as a spacer.
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Diri Ak Pwa

The cultural committee sought out what makes up a typical Haitian dish. The midday meal is the most important, and consisits generally of rice or corn, beans, vegetables, and sometimes meat. These ingredients are often mixed together into one dish.
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To better understand the taste of Haitian Cuisine, the cultural committee researched different dishes, and decided to prepare Diri Ak Pwa (pictured left). The main ingredients are onion, bell pepper, tomato sauce, red kidney beans, white rice, garlic, butter, thyme, and oregano. It was relatively simple to prepare and took about 45 minutes.  The team found it to be tasty, but in need of a little seasoning (salt and/or hot sauce, depending on your preferences).

Fried Plantains

Plantains are a fruit similar in shape to a banana, but with a starchier taste. In Haiti they are fried as a treat for special occasions. The plantains are cut into thick slices and fried until the outside begins to become crispy. they are then removed from the oil, pressed slightly, soaked in a mixture of water, lemon, and salt, then returned to the pan to be fried again. the end result is a crispy. sweet, delicious treat!
The cultural committee practiced this technique, then prepared them and gave out free samples during EOH. 
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For EOH, the stoves committee made a glass TLUD to help demonstrate the gasification process. Although the glass did not heat up enough to sustain a long burn, we were still able to get a better visual on the way the TLUD works. For more info, take a look at the Research tab.  

Check out the videos!

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Check out some of the awesome strides forward by the fuels committee over the few months!

Lever Press

The first HCSP press was provided by our partner Dr. Paul "TLUD" Anderson. It is designed so that a small amount of force on the lever transfers into a large amount of concentrated force, pressing the loose fuel into a dense briquette. I denser fuel will produce a longer burn.

Wood and Charcoal Briquettes

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using the new press, the team made sample briquettes of varying percentage of newspaper and woodchips. The 100% newspaper and the 100% wood chip briquettes both fell apart; the team determined that a mixture of the two elements is necessary for an effective briquette. 
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At EOH,  fuels teams was also able to make charcoal briquettes using the charcoal remains of burnt wood pellets. The fuel output of these briquettes is yet to be determined. 
 
Feb 21st Meeting 02/21/2012
 
Tonights meeting agenda

Meeting Notes from Dr Anderson

Read Part E on TChar:  http://drtlud.com/

Haiti Trip Report from Berkeley, very useful info!

We may partner with Konbit Shelter near Leogane.  http://konbitshelter.org/ 
Leogane is a major grower of sugarcane!
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We used the combustion analyzer that Chip Energy lent us for the first time on 2-12-2012. It is the CA-6203.
It can measure O2, CO, NO, temperature, and draft pressure, and it can calculate CO2.

We used it on the Chip Energy Stovepipe Stove. 

View our report here: Stoves Results 2-12-2012
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I made a couple new stoves over break, both with triangular components in the hopes of increasing stability and reducing part count. The first was a triangular TTop meant to fit on our charcoal stove. 
The triangular fuel chamber works, but there were a number of problems with this design. 
1. Air leaks: secondary air leaked through the seam in the fuel chamber, allowing direct combustion to be sustained at the fuel level. Creating a good seal is easier with a circular fuel chamber.
2. Stability: the stove was susceptible to being tipped over.
3. Pot Support: even if the stove was stable, it has no pot support.
4. Safety: for the most part, the outer shell remained safe to touch, but there were no handles to remove the TTop.
5. In general, TChar designs are custom fitted to the user's charcoal stove - not good for compatibility.

I hoped to address some of these concerns with a second version, called the TriChar2.0. This design has a circular fuel chamber inscribed in a triangular shell. The chamber is affixed to one of the triangle's sides, which can then slide out to dump produced charcoal. The idea here was to create a stand-alone stove with a chamber that could easily dump produced charcoal into any charcoal stove. 
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Last Tuesday I met up with Lee Hite, Zan Smith, and Ron Gorley - all of whom are involved with the EWB Cincinnati Professional Chapter. Lee Hite is developing simple tools for biomass briquetting and pelletizing. His more recent work has focused on developing an appropriate 1" by 1" pellet for TLUD stoves, and he spent considerable time explaining several designs he tried to achieve this goal. Since the pellet mold is relatively small, forcing the thick and viscous biomass into it becomes a challenge. The biomass solution can be thinned with water, but this increases the number of motions required to form each pellet. He had more success with a simple press for a rectangular log, which would feed well into rocket stoves. Unless a better tool is developed for pellets, it would be more efficient to just quickly cut these logs up into small cubes. See the videos below (my apologies for the vertical orientation):
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We're hosting a stove workshop on Saturday January 21st! There will be stove building and testing, lectures, discussions, and Dr. TLUD will be there. More info and registration here: http://www.cleanstove.org/workshop.html
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