A presentation on parabolic solar collectors to K-12 educators. This was followed up with hands on activities and curriculum development.

1. Parabolic Solar Cookers
• Lonny Grafman
• Most Images from Appropedia
• Outline
– Background
– Basics
– Design Examples
– More Examples
– Math and Physics Resources
– Discussion

2. 1000 watts/m2

3. Solar Box Cooker
aka Solar Oven

4. Solar Parabolic Cooker

5. The Parabola

6. y=ax2 y
f=1/(4a)
f
x

7. The Parabola - Definition
http://www.cut-the-knot.org/ctk/Parabola.shtml#Theorem1

8. The Parabola - Reflection
http://www.cut-the-knot.org/ctk/Parabola.shtml#Theorem1

9. The Parabola
Paraboloid

10. Design Criteria:
Design Objective:
•Use of local materials
•Efficiency
To create a solar cooker
•Durability
from local invasive species
•Ease of use
and waste materials that
•Ease of construction
can pasteurize water and
•Cost
be a cooking alternative to
•Impact on environment
the use of fossil fuels.
•Impact on lifestyle

11. Results:
•Equation: y =.5x2
•Time to boil quart: ~2 hrs
Deformation Lessons Learned:
•more blackberry runners
•more rigid material for rings
Reflectivity Lessons Learned:
•pampas grass too lumpy
•no dull, small can lids

13. Protection from
Dazzles and Burns
• Appropriate focal point size
• Glasses and gloves
• Deep dish focus
• Physical barrier
• Physical separation
• Appropriate system size

14. Define the
Problem
Test and
Gather
Implement
Information
the Engineering
Solution
Design
Process
Analyze Generate
and Select Alternative
a Solution Solutions