1. Electrolysis of Water Peter Lindner Ridgewood High School December 1, 2010

2. Energy can neither be created or destroyed, it can only be changed from one form to another – Albert Einstein

3. ConventionalAlternate

4. How do we store electricity? Through Chemistry Fossil Fuels Batteries Hydrogen

5. Why is Hydrogen such a big deal? Energy Density (Mega Joules per kilogram) Li-ion Battery0.54 Gasoline46.9 Hydrogen120.0 ~ 220 times more energy than batteries ~ 2.6 times more energy than gasoline NO AVAILABLE SOURCE OF HYDROGEN

6. Electrolysis of Water Electrolysis: Using electricity to drive a non-spontaneous chemical reaction H 2 and O 2

7. What do we need? Water Electrolyte (PEM, salt water, citric acid) Metal electrodes (Anode +, Cathode -) Electricity

8. Chemical what Happens Anode (positive): Cathode (negative): OVERALL: 2H 2 O O 2 +4H + +4e - 4H + +4e - 2H 2 2H 2 O O 2 +2H 2

9. What is a PEM PEM – Proton Exchange Membrane Used as fuel cells to produce electricity Must use deionized water Can be run backwards as an electrolyzer

10. Proton Exchange Membrane

11. DEMO 4H + +4e - 2H 2 2H 2 O O 2 +4H + +4e -

12. How do we use the Hydrogen? Fuel Cells (electrolyzer in reverse) Run on H 2 and O 2 to form clean water. Water can then be recycled to electrolyzer.

13. What are we going to do? Setup PEM electrolyzer(s). Produce efficiency curves of PEM using simple circuitry. Determine Hydrogen Generation Rate vs. Power input. Build our own electrolyzer powered by our Solar Cells

14. Electrolyte Solar Cell

15. Design a Power Plant

16. What Industry Wants to Make Solar Cells

17. Electrolysis of Water http://www.youtube.com/watch?v=VnYSw 349qvMhttp://www.youtube.com/watch?v=VnYSw 349qvM

18. Questions???

19. Take Aways Solar cells can make electricity That electricity can be used to produce hydrogen from water Hydrogen can be used to store energy Electricity can then be produced by running hydrogen through Fuel cells. PEM – Proton Exchange Membrane Anode – Positive Electrode Cathode – Negative Electrode