The Global Efficient Cook Stove Project
March, 2013
Dear Participating Teacher,
Thank you so much for your interest in our Global Efficient Biomass Stove Education Project. Based on the successes
that we experienced last year, I believe that this project has the potential to serve as an ideal vehicle through which to
teach students about the use of science and engineering to address a set of interconnected and serious global problems.
I hope that once you have read through this document you will agree!
I thought I would begin by putting together this packet as a little (or not so little!) overview of the project. This packet
essentially contains two different sections:
1. A summary of the student biomass and stove-building project that will culminate in the stove building and testing that
will involve students from 6 schools/school projects in 6 countries, and
2. Background information about the efficient stove movement, deforestation, biomass, and articles/websites specific to
Rwanda, Brazil, Uganda, Tanzania, India and the U.S. for teachers to use to get all interested parties (themselves and
their students) to more or less the same point in terms of their background in the efficient stove movement and all of the
accompanying issues.
It is my goal to have all of this information available on-line (through our cookstove wiki and my TIGed on-line classroom
page - http://brookwood.tiged.org/Science8/), complete with links to the various websites from which I have gleaned
most of the information in this document (see the “Sources” section for the whole list.) But I also thought it prudent to put
together a hard copy of this material, as some of the schools that may eventually become interested in this project may
have limited access to on-line computers.
Once students have a good background in the concepts listed above, the project aims to have students use their
accumulated scientific and engineering understanding to build up to 5 different types of biomass stoves, compare and
discuss the results of the testing of these stoves with students in different countries.
Currently, I will be undertaking the project over a 4 week period from March 26 th to April 22nd. I will be dividing my class of
55 eighth graders into 5 groups and am hoping that each group will work closely on this project with students from one of
our partner schools.
I completely appreciate and understand that perhaps not all (and perhaps none) of the intended partner schools
will have the freedom to allow their students to devote this amount of time to the project. I don’t see this as being
particularly problematic, but perhaps we can look at what is possible in terms of allowing students the chance to engage
deeply with peers from around the world on a worthwhile project (early mornings, late afternoons, evenings, weekends,
etc.)
As you will see by the extent of the background information, the global efficient cook stove movement is an initiative that,
although seriously “under-investigated” in the past, is certainly now starting to get some attention…and rightly so. The
more I read, the more amazed I am that the issues associated with the use of inefficient biomass stoves have not become
more commonly known before now. My first recommendation would be that all participants in this project that have
internet access become familiar with the global efficient cook stove movement by previewing (perhaps with students…)
the following two short videos:
http://www.pciaonline.org/
http://www.ghfn.org/3-stories_videos-individual/cooking-not-killing
I am hoping that the final piece of the project will be a global education campaign, organized by participants in this project,
for students around the world about this very important issue.
Regarding my thoughts on the best way to approach the part of the project involving the stove building, testing, and
analyzing competition/collaboration: Having researched stove testing resources put out by such organizations as
Aprovecho, Mercy Corps, and The Partnership for Clean Indoor Air, in addition to doing some initial stove-building
exercises with a small group of keen Brookwood students, I am fully aware that this part of the project will likely be in
need of major revisions in order to be useable by each of the participating schools. It is my hope that we can
periodically meet on-line to discuss, refine, and eventually implement the project. Here is my comprehensive contact
information so that all might easily track me down to talk about the project.
Name:
Position:
School:
School website:
Rich Lehrer
8th Grade Science Teacher
Brookwood School
1 Brookwood Road
Manchester, MA, USA 01944
www.brookwood.edu
School email:
rlehrer@brookwood.edu
Personal email: richlehrer@hotmail.com
School phone:
978 526 4500 (extension 6270)
School fax:
978 526 9303
Skype name:
richlehrer
Hopefully, this project, and the amazing opportunity that our students will have to work with other students around the
world toward a common goal through the project will be one of the first steps to helping others learn more about these
issues. I encourage everyone to keep in mind that the ultimate aims of this project are to both raise our students’
awareness of the efficient biomass stove movement, as well as to have our students take the next step in terms of
educating others about it, and I look forward with great anticipation to working with you all.
Sincerely yours,
Rich Lehrer
8th Grade Science Teacher
Brookwood School
Table of Contents
Topic
1. The Global Efficient Biomass Cookstove Education Project Overview
A. Project Goals
B. Educational Objectives
C. Intended Partner Schools
D. Specifics of The Global Efficient Cook Stove
Project’s Components
I. Teacher Communication
II. Student Communication
III. Reviewing background research information
IV. Documenting
V. Initial Stove Building Practice
VI. Materials Needed
VII. Building Instructions for 5 Basic Rocket Stoves and Information
for a 3-Stone Fire For The Sake of Comparison
a) 3-Stone Fire
b) 16 Brick Rocket Stove
c) Earth Rocket Stove
Page
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d) 5 Can Rocket Stove
e) Winiarski’s Tin Can Rocket Stove
f) 20L Rocket Stove with Bricks
VIII. Safety and Practice Lighting
IX. Practice Stove Tests
X. Final Collaborative Competition
XI. “Going Global”
2. Background Information
A. An Overview of the Efficient Cookstove Movement
I. Effects of Use of Traditional Biomass Cookstoves
II. What is a Clean Cookstove?
III. Why Now?
B. Global use of Biomass
C. Deforestation
I. Fast Facts About Deforestation
II. Why Are Rainforests Being Destroyed?
III. The Role of Poverty in Deforestation
IV. Population and Consumption
V. How Redd+ Can Help Protect Forests
D. Specific Country Stove and Deforestation Information
I. Rwanda
a) Rwanda Forest Information and Data
b) Rwanda Stove Articles and Websites
II. Brazil
a) Brazil Forest Information and Data
b) Brazil Stove Articles and Websites
III. Uganda
a) Uganda Forest Information and Data
b) Uganda Stove Articles and Websites
IV. Tanzania
a) Tanzania Forest Information and Data
b) Tanzania Stove Articles and Websites
V. India
a) India Forest Information and Data
b) India Stove Articles and Websites
VI. USA
a) USA Forest Information and Data
b) USA Stove Articles and Websites
E. Design Principles for Wood Burning Stoves
I. Introduction
a) Proven Strategies
b) An Introduction to Rocket Stoves
II. Stove Theory
a) How to Improve Combustion
b) How to Improve Fuel Efficiency
c) Common Misconceptions
d) Testing is essential
e) Make Stoves Safe
III. Ten Design Principles
IV. Designing Stoves With Baldwin and Winiarski
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V. Options for Combustion Chambers
a) Option #1 – Floor Tiles
b) Option #2 – Insulative Ceramics
VI. In Field Water Boiling Test
a) Beginning of Test
b) Analysis of Results
VII. Appendix: Glossary of Terms
F. Sources
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1. The Efficient Biomass Cookstove Education Project
Overview
A. Project Goals:
The Efficient Biomass Cookstove Education Project will attempt to accomplish the following goals:
1. global efficient cookstove movement - have students learn about deforestation, global biomass use, stove
design, and the issues associated with the global efficient cook stove movement, especially as they pertain to the
U.S., Brazil, Uganda, Tanzania, India, and Rwanda
2. international collaboration - allow students to collaborate on a problem with others in different countries
3. cook stove collaborative competition - have students research, design, construct, test, and redesign efficient
cook stoves
4. “going global” - have students to document their efforts and then attempt to educate others about the issues
associated with the global cook stove movement.
B. Educational Objectives
As a result of having participated in this stove projects, students will:
- understand the reasons why forests are so vital to the health of our planet, and appreciate why deforestation is such a
serious global problem
- be able to describe what biomass is and how it is used by people across the world
- be able to explain issues specific to the forests of the United States, Rwanda, and Brazil
- understand combustion
- understand what a biomass stove is, and be able to list the factors that can affect the efficiency of a biomass stove, while
explaining why and how they produce these effects
- truly grasp the issues that accompany the use of inefficient biomass stoves around the world, including, but not limited
to: deforestation, respiratory health issues, climate change, gender inequity, security issues, etc. etc.
- discuss the scientific concepts inherent in the use of five different biomass stoves, including but not limited to: energy
sources, climate change, the chemistry of combustion, energy transformations, thermal energy, conduction, insulation,
organic chemistry, experimental design, etc. etc.
- have used the design cycle to research, plan, build, test, refine up to 5 different biomass stoves…and then repeat
- have collaborated with students from their own school and schools around the world in a common learning activity – the
building of a personally designed biomass stove
- have participated in a collaborative stove competition in which students personally design, build and test a cook stove in
order to gain a better understanding of biomass stove efficiency issues
- collaborate with students around the world on a project to document the work done on this project, determine how best
to publicize the issue of efficient biomass stoves, and decide how to best educate other students around the world about
these issues
C. Intended Partner Schools - 2013
Brookwood School, Manchester, Massachusetts, USA – 978 526 4500
http://www.brookwood.edu/
Stove Project Contact: Rich Lehrer
Email: rlehrer@brookwood.edu
Skype name: richlehrer
FAWE Gisozi, Kigali, Rwanda - 250 5825 14
http://www.fawerwa.org/
Stove Project Contacts: MUJUNI Patrick
Email: mujunipk@yahoo.co.uk
Skype name: mujuni.patrick700
Colegio Bandeirantes, Sao Paulo, Brazil – 55-11-5087 3500
http://www.colband.com.br/
Stove Project Contact: Cristiana Mattos de Assumpção
Email: cmattos@colband.com.br
Skype name: cmabaggio
The Kasiisi Project, Kibale National Park, Uganda – 1 617 493 5775
http://www.kasiisiproject.org/
a) Stove Project Contacts (Uganda): Rwabuhinga Francis and Keith Miller
Email: rwabuhinga.francis@gmail.com
Keith Miller <kitokm@gmail.com>
Skype name: Kasiisi Project
b) Stove Project Contact (Cambridge): Elizabeth Ross (Kasiisi Founder)
Email: elizabethross@mac.com
Skype name: Elizabeth Ross
The Magoma Project, Magoma, Tanzania
http://www.2seeds.org/magoma/
Stove Project Contacts: Ben Donahue and Stephanie Kim
Email: stephanie_kim@alumni.brown.edu benjamin.r.donahue@gmail.com
ana.rocha@2seeds.org
Skype name: Benjamin Robert Donahue
The Srishti College of Art, Design, and Technology, Bangalore, India
http://srishti.ac.in/
Stove Project Contacts: Geetha Narayanan, Arzu Mistry, Padmini Nagaraj
Email: geethanar@gmail.com padmini@srishti.ac.in arzu@srishti.ac.in
Skype name:
Massachusetts Institute of Technology, Cambridge, Massachusetts
http://web.mit.edu/
a) Stove Project Contact (D-Lab): Jessica Huang
Email: jahuang@mit.edu
b) Stove Project Contact (Media Lab): Leo Burd
Email: leob@media.mit.edu
UpEnergy, Uganda, Rwanda, World
http://upenergygroup.com/
Stove Project Contact: Erik Wurster
Proyecto Mirador - San Francisco, USA and Honduras
http://www.proyectomirador.org/
Stove Project Contact: Dee Lawrence
D. Specifics of The Global Efficient Cookstove Education Project’s
Components
As mentioned above, although I have taken steps to try to take into account the nature and needs of each of the six
schools that will hopefully be participating in this project, undoubtedly, issues will arise that will require that the project be
changed and modified in order to attempt to have each school accomplish the four above-mentioned goals:
1. learn about the global efficient cook stove movement
2. participate in an international collaboration
3. design, build and test a cook stove for an international collaborative competition
4. “go global” with the movement and the project
Because of the inevitability of changes having to be made to increasing the chances of each school accomplishing these
goals, I would like to assure all involved that none of the information outlining the project in this packet is set in
stone…and in fact, I look forward to modifying some or all parts of it to ensure its success. Having said that I also hope, if
not each of the schools is able to accomplish each of the goals, that there will also be value in having as many schools
accomplish as many of them as possible.
I. Teacher communication
It is my hope that there will be opportunities for the all teacher contacts at each of the schools to engage in at least
several “real-time” (be it through Skype, blogging, conference calls, etc.) conversations to refine and clarify the project in
anticipation of the final student collaborations piece of the project. We are also hoping that our wikispaces cookstove wiki
will be an effective medium through which participating teachers and students are able to communicate with each other.
II. Student communication
As outlined in the “teacher communication” section, I also believe that there is serious value in having the students
involved in this project not only know a little (or a lot!) about the people with whom they are collaborating, but also be able
to engage in real time (and preferable face-to-face through Skype) conversations with each other at each step of the
project (researching, planning, constructing, testing, redesigning, and “going global” with the project.) Again, hopefully the
wiki and our TIGed web portal will facilitate this communication.
III. Reviewing background research information
The background research information resources that I have assembled are intended to give students the necessary
knowledge to achieve the four goals of this project. The cook stove movement information came primarily from 5
organizations committed to the development and dissemination of efficient biomass cook stoves:
- Aprovecho Research Center - http://www.aprovecho.org/lab/index.php
- The Partnership For Clean Indoor Air - http://www.pciaonline.org/
- The Global Alliance for Clean Cookstoves - http://cleancookstoves.org/
- MercyCorps - http://www.mercycorps.org/
- The Charcoal Project - http://www.charcoalproject.org/
Although the ideal would be that all participants in this project would be able to access these organizations’ websites (and
numerous other on-line resources that I have included in this document), I am also hoping to be able to include schools
that may not have reliable internet access. Therefore, I have included much of the information, photos, screenshots of
videos, etc. from these websites in addition to the URL’s associated with the different online resources to allow schools
that only have access to this packet to participate.
IV. Documenting
As the final goal of this project is to give students from each school the tools to be able to “go global” in terms of educating
others about both this project, as well as the global efficient cook stove movement, participating teachers are encouraged
to record (through written, photo, and video documentation) the student results of the various components of the project.
In addition to assisting with the students’ final global education piece of the project, this will also help participating
teachers reflect on the success of the project in order to improve it for future use. Again, hopefully the wiki and our TIGed
web portal will be the perfect forum in which post this documentation.
V. Initial Stove Building Practice
Following the reviewing of the background information with students, the project intends to have students build cook
stoves of increasing complexity and (presumably) increasing efficiency. Although there are dozens, if not hundreds of
various stove designs available for review, I have chosen to provide participating teachers with five different, fairly simpleto-build stove designs that will hopefully give students an excellent understanding of the science and engineering behind
the designing of efficient cook stoves. It is not necessary for all students at all schools to build all 5 stoves, but the
assumption is that the more experience students have with building stoves, the better they will be able to personally
design and build a cook stove using materials and plans of their choice for participation in the final piece of the cook stove
collaborative competition.
VI. Materials Needed
In the event that a teacher wants to follow the instructions shown below to have his or her students build and test any of
the 5 stoves listed in preparation for the final cook stove collaborative competition, he or she will need to gather the
following materials
General Materials Needed For All Practice Tests
-
One type of dry, easily apportioned wood of various sizes
Consistently sized pots for the Water Boiling Test
Consistently sized containers for the Popcorn Test
Water
Popcorn
Paper, cardboard, and a lighter to light the fires
Stopwatch
Balance or scale to find the mass of the wood used
3-Stone Fire test – each group will require:
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3 bricks or stones
eye protection
protective gloves
“Practice Stove” #1 - 16-Brick Rocket Stove – each group will require:
-
16 bricks (preferably made of a refractory insulated material – see video)
partially flattened can to support wood as it is fed into stove
eye protection
-
protective gloves
“Practice Stove” #2 - Earth Rocket Stove – each group will require:
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4 bricks (3 for supports and 1 to help create the “feed chamber”
enough clay or mud to be able to build a reasonably-sized Earth Rocket Stove
metal strip to form “pot skirt”
eye protection
protective gloves
“Practice Stove” #3 - 5-Can Rocket Stove – each group will require:
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1 large (3-4 Liters - #10) cylindrical can
3 smaller (500mL or so) cylindrical cans
tin snips
felt marker or “Sharpie”
eye protection
protective gloves
“Practice Stove” #4 - Winiarski Tin Can Rocket Stove – each group will require:
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large, 15-20 Liter rectangular can
8, 10x25cm (4.5x9inch) thin facing bricks, two broken in half
saw
ruler
knife
hammer/mallet
wire
low-density insulating material (pumice stones, vermiculite, or mud/straw mixture)
clay or mud
(optional: corrugated roofing sheet)
“Practice Stove” #5 - 5 Gallon, 20 Liter Rocket Stove with Insulative Refractory Bricks – each group will
require
Brick making
- clay
- water
- wooden mold
- kiln
- sawdust
Stove
- 20L (5 gallon) cylindrical can
- vermiculate or pumice stone
- 3 metal rods
- 1 standard brick
- cement
VII. Building Instructions for 5 Basic Rocket Stoves and Information for a 3
Stone Fire For The Sake of Comparison
a) 3 Stone Fire
(Reproduced from The Partnership for Clean Indoor Air’s document, “Test Results of Cook Stove Performance”)
As with any tool, the skill of the operator determines how
well the work is accomplished. The 3 Stone Fire can be
operated cleanly, or it can be very dirty and wasteful. Open
fires tend to go out easily, however, and it is a natural
inclination to make an overly large fire or leave smoking
wood under a simmering pot while attending to other work.
The fact that the 3 Stone Fire can be operated with very
different results was confusing to early investigators.
In some kitchens, large fires made for cooking use a lot of
wood and make a great deal of smoke. Small fires are also
made that cook food relatively cleanly. Watching
indigenous experts in the field cook with fire has led to a
better understanding of effective biomass fuel use.
Cooks who are trying to conserve wood tend to meter fuel by pushing wood into the fire, slowly burning the wood at the tip
of the stick. Knowledgeable cooks only need a small, hot fire close to the pot to quickly boil water. Improving upon a wellmade 3 Stone Fire was more difficult than the first generation of designers had expected. Learning from expert users
helped teach engineers how to make better stoves.
It is important to remember that in the Aprovecho lab testing the 3 Stone Fire used less wood and made less pollution
than cooking fires in the field. All of the fires in these tests were carefully made using dry and uniform sticks of Douglas fir
fed into the fire in a controlled way to optimize the performance of all stoves.
Well-constructed 3 Stone Fires protected from wind and tended with care scored between 20% and 30% thermal
efficiency. Open fires made with moister wood and operated with less attention to the wind can score as low as 5%. The
operator and the conditions of use largely determine the effectiveness of operation. Stoves must be tested with careful
repetition in order to minimize variables in test results.”
b) “Practice Stove” #1 - 16 Brick Rocket Stove
(Taken from Larry Winiarski’s Youtube video, “How to Make a 16-Brick Rocket Stove” http://www.youtube.com/watch?v=XSMR2ANIZ7E)
Construct a 16-brick rocket stove using the images below. Ensure that the center brick of the first layer is ½ the height of
the rest of the bricks and that a regular-size brick is used in the front acts as a shelf to lift the sticks off the ground.
Alternatively, a partially flattened can may be used as a shelf.
c) “Practice Stove” #2 - Earth Rocket Stove
(Taken from “The Rocket Stove Design Base”, based on stoves made in DRC refugee camps)
http://www.charcoalproject.org/2010/03/cnns-anderson-cooper-reports-on-stove-project-in-congo/
http://www.rocketstove.org/index.php?option=com_content&task=section&id=8&Itemid=72
Set 3 bricks on end as shown in the diagram on the previous page. Pack a ”donut” of clay or mud around the bricks in the
dimensions shown. Hollow out the feed chamber in order to create “L-shaped” combustion chamber. Insert a metal
cylinder of the dimensions shown above into the mud, resting on the bricks.
d) “Practice Stove” #3 - 5 Can Rocket Stove
(Taken from “LDS Prepper’s Youtube video: “Build a Rocket Stove: Step-By-Step” and Niels Corfield’s Youtube Video:
“Rocket Stove Workshop”.
http://www.youtube.com/watch?v=P6ValmUnjz4&feature=related
http://www.youtube.com/watch?v=j8z5befz6ew
Wearing your safety gloves and using tin snips, remove the top and then measure and cut a circular hole, the diameter of
one of the smaller cans in the side of the large (#10) can in the location shown in the photo below. Cut both ends out of
one of the small cans. Cut the top of a second small can, then measure and cut a circular hole of the same size in the side
of this second small cans in the location shown in the photo below. Place the second can in the larger can as shown and
then construct an “L-shaped” combustion chamber from two cans. Remove the two ends of the third small can, slit the
side, and fit it in the second can as a chimney. Fill the space between the “L-shaped” combustion chamber and the inside
of the larger can with vermiculite. Cut a donut shaped hole in the removed top of the larger can and place it over the top of
the can. Use the 4th small can to make a shelf that will support the wood in the feed chamber.
e) “Practice Stove” #4 - Winiarski’s Tin Can Rocket Stove
(Taken from Pat McCardle and The Solar Cookers International’s Youtube video: “How To Make a Tin Can Rocket Stove”
featuring the inventor of the rocket stove, Larry Winiarski showing his design.)
http://www.youtube.com/watch?v=gO-vPyCShLg&feature=player_embedded#!
Construct a chimney as shown in the photos below using the 4 thin facing bricks, ensuring that you use the wire to fix the
bricks in place. Cut 1cm from the bottoms of 3 of the chimney bricks, leaving one longer than the others. Measure the
dimensions of the feed chamber and cut two flaps in the side of the can using the tin snips in the side of the rectangular 5
gallon (20 Liter) can, ensuring that you retain the cut piece and bend back the flaps made of the side of the can. Insert the
remaining 4 bricks (3 whole bricks, 1 cut in halve) to assemble the horizontal tunnel as shown. Pile pumice stones or
vermiculite between the inside of the can walls and the tunnel to keep the bricks in place as the tunnel is assembled.
Secure the metal wings of the hole to the outer part of the horizontal tunnel using wire. Place the chimney on the
horizontal tunnel, long brick forward. Fill in the space between the chimney and the can with the low density material (see
photo below). Finish the top of the chimney with clay and place 4 small brick spacers, inserted into the wet clay, that will
hold the pot. If desired, construct a pot skirt out of the tin roofing.
f) “Practice Stove” #5 - 20 Liter (5 Gallon) Rocket Stove With Insulative
Refractory Brick Making Instructions
(From Aprovecho’s Youtube video: “Build A Rocket Stove”)
http://www.youtube.com/watch?v=YIMi0DVDvqw&feature=player_embedded#!
The primary difference between this stove and the one previous is the fact that this one includes instructions on how to
make low density, insulative refractory bricks, uses less of an “L-shaped” combustion chamber and the body of the stove
is cylindrical and can be made from sheet metal or a large 20L can.
Begin by making the bricks. Mix 500g of dry sawdust with 900g of moist clay and 1200g of water. The final bricks will need
to be fired in a kiln at 1000 deg C. Make a wooden mold for the bricks. Wet it and fill it with the clay/sawdust/water
mixture. Push the mixture into all corners of the mold. Push the unfired brick out of the mold. Make ___ of these bricks.
Construct the combustion chamber using these bricks and one regular, durable brick. The first layer is a “U-shaped”
arrangement (as viewed from the top), with the regular brick forming the back of the “U” and the open part of the “U” being
the feed chamber. The next layer is made of 2 complete bricks (in the front, over the feed chamber and in the back over
the regular brick) and 2 half-bricks on the sides. The 3rd later is reversed, having the two half bricks in the front and back
and the whole bricks on the sides.
The combustion chamber should be 30cm tall and the inside of the chimney should be 10cm x 10cm.
Use a cylinder made from a large can with the ends cut out or sheet metal to surround the brick combustion chamber. Cut
a rectangle as shown above to match up with the fuel entrance. Slip the cylinder over the combustion chamber and
temporarily place a brick in the rectangular entrance. Fill the space between the combustion chamber and the metal
cylinder with a vermiculite (or pumice stone) and cement mixture. Cut 6 holes in the top of the cylinder that will support a
triangle of metal rods on which the pot will be placed. There should be a 12mm gap between the pot and the metal
cylinder and the pot should sit on the pot supports above the combustion chamber.
VIII. Safety and Practice Lighting
As students will be using fire, heating surfaces, and using tin snips in the construction of their stoves, there is the potential
for danger in most of the practice stoves. Standard lab safety should be used to ensure that students are not injured
during this project. Protective eyewear should be used, heat and cut resistant heavy gloves should be worn, long hair
should be tied back, floppy sweater should be removed, and long sleeves should be rolled up. Sharp metal edges should
not be touched and should be filed or sanded down.
Students should also be given ample opportunity to practice the effective lighting of their stoves in order to ensure that
stove results are truly dependent on stove design, and not which students are the best at lighting their stoves and keeping
them lit. In the practice sessions held with students leading up to the creation of this packet, the following issues were
observed and possible solutions generated:
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clothes and hair became very smoky (may be tough to avoid…tall chimneys? Cover hair? Wear “testing clothes”?)
difficult to keep wood lit (wood must be dry, lit with very small pieces first, lit using paper and cardboard, and kept
off the ground as it is fed in by using a small shelf, easily made with a partially flattened can)
much blowing was needed, students because dizzy, occasionally breathed in smoke (should be remedied if wood
burns better)
students became quite dirty, kneeling on ground, handling sooty equipment (wear “testing clothes” and use
gloves)
wind became a factor because of need to test outdoor (ensure testing is done outdoors in a sheltered area)
when a competition was being held, students became excited and work became frenetic, and not always based
on sound ideas or safe practices (ensure that students are working calmly and safely)
students had not gathered enough biomass and had to go searching during competition (ensure that ample
biomass is gathered and dried before testing)
teams with more students had an advantage (ensure that teams are same size)
teams that starting testing before wood was burning had unfair advantage of heat from paper/cardboard (ensure
that wood is alit and burning before starting competition)
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the more often students tested stoves, the better they got at building and lighting stoves, and keeping fire lit
(ensure ample opportunities to make fires, build stoves and test stoves. See below.)
IX. Practice Stove Tests
Practicing stove building and testing using pre-ordained stove designs will allow students to:
- become proficient at the building and lighting of stoves
- familiarize themselves with what works and what doesn’t in terms of materials and designs that make stoves more
efficient, and to analyze the science behind successes and failures
- gain experience in the research gathering component of the design cycle
- make decisions on what design principles and material choices they will use for their final stove design entry in
the collaborative competition
- generate a list of suggestions and recommendations that they can share with their international partners
The point of the practice stove portion of the project is not to tell students what design to use in the final collaborative
competition, but rather to allow them to gain information that will inform their own final stove design. During the practice
stove attempts, the emphasis should always be on the recording of test results, and the use of these results to make final
stove design decisions. Again, it is not essential that every student build every practice stove, but the more experience
students have building and testing stoves, it is assumed the better their final products will be.
It is understood that the final means to test stove performance will be decided upon by the participating teachers.
However, the testing of practice stoves should directly mirror the tests that will be used in the final competition, and should
be based on the methods that are actually used to test real stoves and stove projects.
X. Final Collaborative Competition
There are a number of controlled stove testing methodologies that are used by various organizations to judge the
efficiency of stoves (those listed at the end of the background research packet were a simplified version of the University
of California Berkeley (UCB)/Shell Foundation revision of the 1985 VITA International Standard Water Boiling Test.)
Resources that outline testing methodologies include:
http://www.pciaonline.org/testing (an amazing collection of the science of stove testing!)
http://www.rocketstove.org/index.php?option=com_content&task=section&id=11&Itemid=90
http://berkeleyair.com/publications/cat_view/42-publications
Typically, testing organizations attempt to determine the efficiency and effectiveness of stoves in a variety of ways. These
include:
- A Water Boiling Speed Test – As outlined by the PCIA, in general the test consists of three phases. These are: (1)
bringing 5L of water to a boil from a cold start; (2) bringing water to a boil when the stove is hot; and, (3)
maintaining the water at simmering temperatures.
- A Water Boiling Fuel/Energy Use Test – Again, as outlined by the PCIA, this test calculates the amount of fuel
and the amount of energy needed to boil water, and often to keep it simmering for 45 minutes. Typically, the mass
of wood or charcoal is measured before and after the test. Conversions to kJ of energy used are used to compare
stoves that use different types of fuel (wood, charcoal, propane, etc.)
- A Controlled Cooking Test – The amount of fuel needed to cook specific, locally determined dishes by local cooks
is measured
- Particulate Matter (PM) emissions – typically uses probes in a collection hood to measure the amount of PM, one
of the leading cause of respiratory diseases in biomass stove users
- Carbon Monoxide (CO) emissions – uses probes in a collection hood to measure this poisonous gas
- A Test Kitchen Test looks at the quality of air at different locations in an actual kitchen
- Safety Tests look at such factors as stability, exposure of heated surface, jagged edges, etc. or anything that
could put users or children at risk
- Cost – both to purchase/build and to use over time.
Once effective test that was used during the development of this project was the use of popcorn to determine heat
produced (first kernel popped, first stove to pop all kernels, etc.) This test removed some of the subjectivity of determining
when boiling had occurred and provided an element of entertainment to the tests.
In our project, participating teachers will conference in order to allow each school to determine the best method to assess
efficiency and effectiveness of the stoves built by student. Without a doubt, WBT’s and Fuel Use tests are the standard
method for comparing efficiencies and should likely be used in this project. Additionally, the other methodologies listed
above may play a role in determining stove quality, particularly if a cheap and effective way of measuring PM and CO can
be found.
XI. “Going Global”
The final piece of the project involves students from each school collaborating to take, what they have learned in their
background research, practice stove testing, performance in the final collaborative competition, conversations with
authorities, and collaborative work with students in other countries to educate others around the world. There are a
number of forms this could take, and could involve such things as posting photos, slide shows, etc. of the various parts of
the project, creating Youtube videos to outline the project, creating websites to publicize the project, contacting local,
national and international press and organizations to inform them of the project, etc.
Conveniently the Taking It Global education (TIGed) portal provides users with many resources to undertake just this sort
of “going global” project. Of particular interest is their “Guide To Action” document that is tailor made for this project.
Below is the outline of the process advocated by TIGed in order to effectively “provide students withy the direction and
support they need to better work towards making the change they want to see in the world.”
The Guide to Action includes many helpful recommendations in terms of how to perform such tasks as working with a
team, identifying networks, setting goals for projects, creating a group project plan, promoting a project on TIGed,
implementing a project, focusing on having a lasting impact, and even lists challenges that students typically face in
“taking an issue global” and provides tips for dealing with these challenges.