KENYA DESIGN REPORTBy: Kevin LaFevers, Anthony Sabatino, Xiaoming

Liang, Richard Wilson

Table Contents1. Recognize the Need2. Problem Statement3. Mission Statement4. Customer Needs Assessment5. Design Specifications6. Design Aspects 7. Design Ideas8. Decision Matrix9. Final Design10. Cost Analysis11. Summary

Recognize the Need We recognize the need to provide a stove

system that is safe and can be used by the majority of third world countries

Problem Statement Current cooking systems are inefficient

and harmful to users who inhale smoke while cooking indoors

Must be cheap Limited resources

Mission Statement We intend on creating a low cost,

sustainable, and culturally appropriate cooking system for use by the poor and marginalized people in the developing world.

Customer Needs Assessment

Objectives Durable Well insulated Efficient Safe Locally made Made of local materials

Customer Needs Assessment con’t

Constraints Cheap Low emissions Simple design Similar in size to current models

Features Simple fuels Ability to Upgrade

Design Specifications The stove must cost less than $20 (U.S.) It must be able to heat a quart water to

100 degree Celsius in under 10 minutes It must emit 50% less than current stove

systems It must use 50% less fuel

Design Aspects Materials were decided upon with

efficiency and cost in mind Insulation material for designs will be a

clay shell filled with ash Ceramic material will be used as a sturdy

insulator A steel shell will enclose the stove for

protection

Design Idea 1 This design features a “bowl-shaped heat

exchanging surface” which provides high heat exchange rate and therefore high efficiency, which saves a lot of energy.

Design 1

Design Idea 2 Uses a simple ceramic pipe as a center A bowl shaped pot is used for maximum

heat transfer A steel casing is used around the clay Steel supports are used to lift the bowl off

of the stove for ventilation

Design 2

Design Idea 3 The heat exchange area is cone shaped

to increase the heat transfer Steel supports are used to lift the pot

away from the body of the stove to increase airflow

Steel casing for protection

Design 3

Decision MatrixDesign 1 Design 2 Design 3

Initial Cost x3 4 4 3Efficiency x5 2 3 5Ease of Manuf. x4 4 4 3Portability x1 4 4 4Ease of Use x3 3 3 3Safety x3 5 5 5 Total 66 71 74

Selected Design 12” in diameter, 18”

high 3” Clay shell filled with

ash ½” thick ceramic inner

combustion chamber 1/8” Steel outer shell

wrapped around the clay Fuel pellets

Design Drawings

Cost Analysis Scrap steel is approximately $.10 per

pound Clay is approximately $.25 per pound Ceramic chamber is approximately $1.00

per pound Cost of ash insulation is negligible In total, steel will be about $1, $3 for

clay, $2 for ceramic Final material cost will be around $6

Summary We feel this stove system will provide a

low cost, sustainable, and safe alternative to currently available systems

The design is simple and utilizes locally available materials, which will allow unskilled workers to manufacture and repair it

References1. Aprovecho Research Center. "Methods for CApturing Heat." Capturing Heat.

Web. 1 Nov. 2009. <http://weblife.org/capturing_heat/>. 2. Bello, Dr. Emmanuel. "The Ceramic Jiko Stove." The Ceramic Jiko Stove

Information Page. Web. 3 Nov. 2009. <http://ces.iisc.ernet.in/energy/paper/tech101/jikostove.html>.

3. "Castable Refractory." Castable Refractory. Ellis Custom Knifeworks. Web. 1 Nov. 2009. <http://home.comcast.net/~eellis2/EllisCustomKnifeworks/castablerefractory.html>.

4. "Clean Cookstoves Overview." Envirofit - Making the World Fit for Humanity. Ed. EnviroFit International. Web. 29 Oct. 2009. <http://www.envirofit.org/?q=our-products/clean-cookstoves>.

5. Oliver, Lionel. "Homemade furnace refractories." Melting metal in a home foundry, backyard metalcasting, metal casting. 12 Jan. 2002. Web. 1 Nov. 2009. <http://www.backyardmetalcasting.com/refractories.html>.

6. Renewable and Appropriate Energy Laboratory (RAEL), University of California, Berkeley. "The Kenya Ceramic Jiko." Kenya Ceramic Jiko. Web. 2 Nov. 2009. <http://www.solutions-site.org/kids/stories/KScat2_sol60.htm>.