1. Andrew Huizenga Lindsay Arnold Diane Esquivel Jeff Christians

2. Overview – Need http://scienceblogs.com/ ? http://farm1.static.flickr.com/35/74109013_0359f3f160.jpg

3. Overview – Objectives  Develop a commercially viable Microbial Fuel Cell (MFC) Sustainable Portable Simple operation Inexpensive http://farm1.static.flickr.com/35/74109013_0359f3f160.jpg

4. Overview – How it Works

5. Design – Norms  Intuitive Easy operation Low maintenance  Stewardship Cost effective Eco-friendly  Cultural Appropriateness Attainable ingredients

6. Design – Alternatives  Electrode Stainless steel Graphite Platinum loaded graphite  Membrane Proton Exchange Membrane (PEM) Salt bridge  Feeding Process Continuous Batch  Semi-Batch

7. Design – Experiments  Media simplification (substitution/elimination)  Bacterial growth kinetics  Extreme environment resistance  Electrode surface area to chamber volume

8. Design – Results  Final media Baking soda, vinegar, table salt, phosphate, ammonium chloride in water  Similar results temperatures 65-86 °F  Withstands extreme variation in media  Surface area : volume ≈ 1in 2 : 1in 3

9. Prototype – Block Diagram

10. Prototype – Model Design

11. Prototype – final cell

12. Prototype – Results  Maximum Voltage 0.666 Volts at 979 kΩ  Maximum Power 0.5 μW 200,000,000 MFCs to power a standard 100W bulb 1,400,000 MFCs to power an iPod Touch  MFC in operation since April 15 th

13. Future Work – Marketing  Sell all materials as an MFC kit  Final unit cost ≈ $10.00

14. Future Work – Upgrades  Add platinum loaded graphite electrodes 1,000 – 10,000 times output  Combine different bacterial species 10 – 100 times output  Best case: 20 MFCs to power 100W bulb <1 MFC to power iPod Touch

15. Conclusions Successful prototype Sustainable Portable Simple operation Inexpensive  Technology has potential 22 μW / m 2 of electrode Similar cells have produced ≈ 10-20 mW / m 2

16. Questions?