Hot Box

Sponsored By: Shell

Engineering Design 100 Section 006

Team 3: Cash Money Millionaires

Submitted to: John Klinger
Date of Submission: December 11, 2009

(listed from left right)
Mike Rekun (, Steve Zoranski (,
Nick Corey (, Tyler Quinzan-Singer (

Hot Box 


Problem Statement: To efficiently help the Kenyan people develop a low cost, low emission, and quality cooker.

Abstract (Mike Rekun) :

To design an efficient way of cooking for developing countries, we needed to develop a system that was inexpensive, safe, and sustainable. After researching the current technologies available and brainstorming several concepts, we selected what we believe is the best idea of a sustainable cooking product. Our concept is a hybrid of current technologies available, allowing the consumer to utilize solar power alongside traditional combustion of fuels to heat food. This product is affordable, costing  $6, economically and environmentally friendly, and safe to use as all harmful emissions are disposed of outdoors, away from the user and their loved ones.


Table of Contents:

1.0 Introduction (Steve Zoranski)

2.0 External Research
        2.1 Online Research
                2.1.1 Existing Technologies (Nick Corey)
                2.1.2 Solar Cookers (Mike Rekun)
                2.1.3 Biomass Cookers (Tyler Quinzan-Singer)
                2.1.4 Charcoal Production/ Briquette Manufacturing (Steve Zoranski)
        2.2 Benchmarking of Current Systems (Nick Corey)

3.0 Customer Needs Analysis (Tyler Quinzan-Singer)

4.0 Concept Generation/ Selection
        4.1 EMS Model (Mike Rekun)
        4.2 TRIZ Matrix (Tyler Quinzan-Singer)
        4.3 Top Concept Sketches (All)
        4.4 Concept Selection Matrix (Nick Corey)

5.0 Final Design
        5.1 Explanation of Design (Steve Zoranski)
        5.2 EMS Model of Final Design (Mike Rekun)
        5.3 Cost Analysis (Tyler Quinzan-Singer)
        5.4 CAD Model (Nick Corey)
        5.5 Prototype Model (All)
        5.6 Conclusion (Mike Rekun)

6.0 Other
        6.1 Schedule of Project (All)
        6.2 Power Point Trifold (Nick Corey and Mike Rekun)

7.0 Conclusions (Mike Rekun)

8.0 References (Tyler Quinzan-Singer)

1.0 Introduction
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When the Envirofit project was introduced by Shell, our team began the process of researching the product. Our team was asked to develop an affordable, environmentally friendly cooker that was to be used as a mainstream cooking stove in Kenya.  After researching the product for some time, we developed a problem statement so we could better formulate our concepts and solutions. One of the main problems we identified was that the Envirofit cooker was releasing harmful smoke and ash. This would pose a threat if the cooker was to be used inside a poorly ventilated house. Another problem was the high price of the Envirofit.
With these issues in mind, our team began to generate needs statements for our new concepts. To supplement the needs statements, our team also researched various cooking methods, drew up an EMS model, and completed a TRIZ matrix; all of which can be found in the following report.
  After eliminating erroneous ideas via benchmarking, we decided on combining both solar and biomass cooking methods. Our final concept combines these two different methods so as to include the best aspects and eliminate the setbacks of each.

2.0 External Research
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2.1 Online Research

Existing Technologies

Solar Cookers

Biomass Cookers (In General)

Charcoal Production/ Briquette Manufacturing

2.2 Benchmarking of Current Systems

Benchmarking is rating different models of cookers against each other.  The point of a benchmarking table is to figure out which model is the most desirable to the Kenyan people.  After doing the table we found out that the Jiko is the most desirable for the Kenyan people.  The reason the Kenyan people like the Jiko is so desirable is because it works anywhere and is so cheap.  Most Kenyan people use Jiko's which agrees with our benchmarking table.  

3.0 Costumer Needs Analysis
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According to our research and information found at the shell project website low emissions is the most important factor when buying a cooker. In addition to that, low cost as well as working rain or shine are important features in a cooker. We also found that having high energy output is not a high priority.

4.0 Concept Generation
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EMS Model

An EMS Model is used to describe the energy in materials in a system to describe the harmful side affects and where the problems may lie.
In this model the Fuel and flame are introduced to the cooking pit. Here you can see that our first setback occurs at the amount of money spent on fuel. Energy is given off from he cooking pit in the form of heat to both the cooking pan and the household. The heat given off from the pan is used to cook the food and then the food is consumed by the occupant. However, the emissions from from cooking pit are breathed in by the occupants. From this we learn that the main problems are with the cost of fuel and emissions.

TRIZ Matrix

We wanted to improve the adaptability while keeping our current reliability the same. In order to do this we used the inventive principles listed below.

Using these principles, as well as a few others, we came up with the following 10 brainstormed concepts

Charcoal Cooker- Simple cooker using charcoal as fuel rather than wood in order to decrease emmisions
Simple Cheap Solar Cooker- sustainable energy source, not too expensive. Limited to time of day used.
Complex Solar Cooker w/ battery- Solar energy is stored in a battery, now able to be used during all times of the day
Solar Cooker w/ heating rocks during the day- Solar cooker heats rocks in order to keep heat that can be used during the night or a cloudy day
Ventilating the house- Fumes are ventilated out of the house in order to keep the users from breathing in toxic gases
Filtering the fumes- Filter attachment to the cooker in order to only allow clean air out leaving the toxins in the filter
Heating water using solar power- heated water is used to cook food and store heat
Insulated Cooker- Similar to current cookers with more insulation to keep the heat concentrated towards heating the food rather than escaping into the environment
Hot Box- Solar cooker with ability to use biomass fuel to cook when solar energy is insufficient. Attached to the house in order to keep smoke outside while cooking inside
Jiko with Muffler- Similar to the jiko with a muffler attachment that directs smoke away from the user.

Top 4 Concepts

Charcoal Cooker- Simple cooker using charcoal as fuel rather than wood in order to decrease emissions.

Jiko with Muffler- Similar to the Jiko with a muffler attachment that directs smoke away from the user.

Simple Solar Cooker- sustainable energy source, not too expensive. Limited to time of day used.

Hot Box- Solar cooker with ability to use biomass fuel to cook when solar energy is insufficient. Attached to the house in order to keep smoke outside while cooking inside.

Concept Screening Matrix

After the concept screening matrix we decided to continue with our design of the Hot Box because it proved to be a better product for the Kenyans.

5.0 Final Design
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Full Explanation of Design

The Hot Box is designed to primarily use solar energy as a heat source to cook food. As a supplement to solar energy, a biomass cooker was also integrated into the design. This was done so that the Hot Box will be able to cook food at anytime during the day. The process of cooking begins as the sun’s rays are channeled into the box via the reflectors that surround an opening in the box. The Hot Box itself will be made out of a ceramic material which will act as an insulating agent. A clear plastic window will allow the sun’s rays into the Hot Box without letting heat escape.
Inside the Hot Box, a removable cast iron shelf will be placed. Food can be inserted or taken out of the Hot Box from the back where a hinged door will let consumers access the food. The shelf will act as the cooking surface, and it will allow for the biomass fuel to be inserted underneath the shelf. Since the biomass will be cooking inside a closed box, a hole will be in the top of the Hot Box to allow smoke to leave the box. All together, the price for the Hot Box will be $6.00 with a 20% profit included.


EMS Model of Final Design

Using the revolutionary Hot Box fuel and flame are both introduced as well as sunlight to heat the food as described above. The amount for money spent on fuel is dramatically reduced. This eliminates one of our main problems. Also the emissions are given off outside of the household, far from the lungs of the consumers.

Economic Analysis

According to the average income of a Kenyan, it would be very difficult to pay the six dollars required to purchase a Hot Box. As producers, we think that this is a very fair price. In order to make it plausible for the Kenyans to purchase the Hot Box Cash Money Millionaires have offered to supply the Kenyans with a 2 month installment plan where they pay for the first third up front, then the next third at the end of the first month, and the last third before the end of the second month. We also think that through using the Hot Box it will save them significant amounts of Ksh.

Image of CAD Model



These are pictures of the Hot Box.  The Hot Box features table to cook the food on, while underneath the table will go the biomass fuels used to cook the food.  If it is a bright and sunny day then biomass fuels will not be necessary the suns rays will provide the energy to cook.  The Hot Box will attach to the wall of a house and will be accessible from inside, while any emissions will escape to the environment. 

Image of Actual Model


This is a picture of our model.  The cardboard shell will be made of ceramic, and the part saran wrap will be made of plastic sheeting.  There are panels to capture the sunlight, and the food is inserted from the reverse door.

6.0 Other
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6.1 Schedule

This is a schedule of the tasks that needed to be completed in the time frame given of 7 weeks. As a group we split up who was responsible for any given task, however we all were to help make sure the task was fully completed and that everything was the best that it could be.

6.2 Power Point

This is the power point slide that we used as our tri fold during the presentation. It has basic information about the Hot Box  and our design process.

7.0 Conclusion
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In order to provide a solution to the traditional methods of cooking used in Kenya, we first needed to establish exactly what problems must be solved. After doing so we realized that our main focus would be creating a cooking system that was cheap enough for a family that lives on two dollars a day to afford, and one that greatly reduced the amount of emissions that are currently exhausted within the household and responsible for many deaths each year. Once our problem was stated, we looked at the current products that were available to these people and ranked them on how well they serve the people's needs.
Using this knowledge along with an EMS model and TRIZ matrix, we were able to brainstorm 10 concepts that we believed would improve the current situation. Through concept screening, we were able to quickly narrow down these ideas into the four top choices, which we expanded upon. These four concepts were a charcoal cooker, Jiko with muffler attachment, simple solar cooker, and the Hot Box idea that we eventually chose using concept selection methods.
Our Hot Box design was in our eyes the best solution to the Kenyans' problems because it saves them money on fuel and eliminates emissions from the household. Costing only $6US a simple payment plan could be used to purchase the Hot Box, and its help from solar cooking reduces the amount of money spent on fuel in the long run. It is also a sustainable way of cooking, since the product can be made in the area, providing jobs to the people who create the product, or repair it. What sets our design apart from the other options are the amount of choices it provides its users. The customer can decide whether they would like to cook indoors or outside, and how much fuel they would like to use based on personal taste or how much time they are willing to take to cook. All of these options combine to provide the Kenyans with the safest, cheapest, and most efficient way of cooking their favorite dishes.


8.0 References
(Back To Top)

Bhaskar Reddy, Sai. "GEO Fuel Briquettes." 18/4/2009. Web. 20 Nov 2009. <>.

"Convert Currency, Kenya." Web. 5 Dec 2009. <>.

"How Solar Cookers Work." Solar Cookers International. Web. 8 Dec 2009. <>.

"Kenyan Ceramic Jiko." The Salad Magazine. 23/5/2009. Web. 4 Dec 2009. <>.

Meicherczyk, Rudiger. "Charcoal and the Environment - Pros and Cons." Web. 18 Nov 2009. <>.