Activity 1.3.1 Solar Hydrogen System VEX Purpose Hydrogen is the most plentiful element in the universe. It can be burned in oxygen to produce heat or combined with oxygen in a fuel cell to produce heat and electricity. Hydrogen on Earth is found bonded with other elements; for example, bonded hydrogen and oxygen comprise water. Hydrogen can be stored once it has been separated from other elements. Hydrogen can be captured in several different ways. The most economical way to harness hydrogen is through existing fossil fuels. Engineers and scientists are working to find ways to decrease the cost of harnessing hydrogen from other sources like water and some forms of algae. Hydrogen storage and transportation U.S. Department of Energy Equipment Hydrogen fuel cell Solar module Distilled water Solar hydrogen automobile Wires Multimeter or other probes for measuring voltage and current Light with a 120 Watt PAR38 incandescent bulb, or as recommended in the manufacturer s instructions Stopwatch or other timing device Tape measure 5-10 Ohm resistor Procedure In this activity your team will use a solar module to produce electricity. You will use the electricity from the solar module to separate hydrogen from oxygen, harness the hydrogen, and then use the hydrogen as fuel. Although teams will complete this activity, each student should individually complete this entire document. POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 1
This activity was written to be used with the Heliocentris fuel cell. If you are using the fuel cells from a different manufacturer, refer to the manufacturer s instructions to be sure that the equipment is used as designed. 1. Read the Fuel Cell User Guide. 2. Follow the directions in the Fuel Cell User Guide under the section Preparing the Fuel Cell for Use. 3. Set your multimeter to measure voltage. Connect multimeter test leads to the solar panel terminals. Shine the light source on the solar panel always keeping at least 8 inches of separation between the two. Move the solar panel or light source to determine the location that produces the highest voltage value. You may want to mark the positions with some tape. Record the no load voltage value. Open Circuit Voltage 4. Set your multimeter to measure current. Return the solar module to the same exact position that produced the highest voltage value and measure the system s current. Record the no load current value. Short Circuit Current 5. Calculate the amount of power that would be produced by the solar module if it could simultaneously produce the voltage and current you measured. Power = Power = Voltage x Current POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 2
6. Attach the solar panel to the solar hydrogen automobile. Position the automobile drive motor so that the wheels are not in contact with the ground. Connect the automobile motor leads to the solar panel. Position the light source to produce maximum voltage leaving a minimum distance of 8 inches between solar panel and the lamp. Is there enough power to turn the motor? 7. Lower the wheels to the ground. Can the solar panel power the car on the ground? If the automobile will travel, record how long it takes for the car to travel 5.0 ft. Calculate the automobile s speed in ft/s. 8. Set your multimeter to measure voltage. Connect multimeter test leads to the solar panel terminals. Record the load voltage value.(drive gear should be engaged) 9. Load Voltage 10. Set your multimeter to measure current. Connect multimeter test leads to the solar panel terminals. Record the load current value (drive gear should be engaged). Load Current 11. Calculate the power delivered by the solar module when it is loaded by the motor with the wheels on the ground. Load Power 12. Charge the fuel cell by using one of the power sources according to the directions in the Fuel Cell User Guide under the section Powering the Fuel Cell (Electrolysis) POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 3
13. After the fuel cell is fully energized, set the multimeter to read voltage. Connect the multimeter test leads to the fully energized fuel cell terminals. Record the voltage value. Open circuit Voltage 14. Set the multimeter to measure current. Attach a 5-10 ohm resistor to the positive terminal of the fuel cell. Connect the multimeter test leads to the fully energized fuel cell s negative terminal and chosen resistor. Record the current value. Load Current for resistor Connect the free end of the resistor to the negative terminal of the fuel cell and record the voltage across the resistor. Load Voltage for resistor 15. Calculate the power produced by the fuel cell. Power = Power = Voltage x Current 16. Attach the fuel cell to the solar hydrogen automobile. Position the automobile so that the wheels are not in contact with the ground. Connect the automobile motor leads to the fuel cell. Is there enough power to turn the motor? 17. Lower the wheels to the ground. Can the fuel cell power the car on the ground? If the automobile will travel, record how long it takes for the car to travel 5.0 ft. Calculate the automobile s speed in ft/s. POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 4
18. Set your multimeter to measure voltage. Connect multimeter test leads to the fuel cell terminals. Record the load voltage value (drive gear should be engaged). Load Voltage with motor 19. Set your multimeter to measure current. Connect multimeter test leads so that current to the motor passes through the meter. (Disconnect one alligator jumper cable and connect one meter test lead to the fuel cell in its place, and connect the other test lead to the jumper cable.) Record the load current value. Load Current with motor 20. Calculate the power produced by the fuel cell when it is loaded by the motor with the wheels in contact with the ground. Fuel cell power with motor 21. Which system had a higher power value? 22. Compare and relate the fuel cell and solar cell power values to travel speed. POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 5
Conclusion 23. Based on your observations, what are the advantages and disadvantages of a car utilizing solar power? 24. Based on your observations, what are the advantages and disadvantages of a car utilizing hydrogen fuel cell power? 25. Describe and defend a system that you believe would best utilize a solar hydrogen system to meet the needs for an average driver. 26. How does a photovoltaic cell work? Record the source of your information. 27. Detail how electrolysis separates hydrogen and oxygen. How is electricity produced by the bonding of hydrogen and oxygen? Record the source of your information. POE Unit 1 Lesson 1.3 Activity 1.3.1 Solar Hydrogen System VEX Page 6