Gain an understanding of how the vehicles work. Determine the advantages and disadvantages of each

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1 Title- Alternative Energy Races Subject/s and Grade Level/s- Overview- Earth Science or Physics, Grades 7-9. This lesson demonstrates the operation of alternative energy vehicles, namely hydrogen fuel cell and photovoltaic (solar) electric vehicles. Students will become familiar with how each works through hands-on experience. The advantages of each technology and challenges in their operation will be demonstrated. Objectives/ Students will be able to:- Gain an understanding of how the vehicles work Determine the advantages and disadvantages of each Develop basic data collection, reduction, and record keeping Work in groups Materials required- Hydrogen Kit Cars (1-5, ~$100 ea.) Solar Kit Cars (1-5 ~$40-80 ea.) Roofing Paper/ Similar material (~$30) (purpose is to create a smooth surface outside, typical pavement or concrete is too rough for the kit cars to operate effectively roofing paper is typically 3 feet wide and in long rolls.) Distilled Water (for H 2 generation) AA Batteries (for H 2 generation) Stopwatches

2 Tape Measures (NOT spring loaded if possible, or students should be instructed on how to properly retract a spring loaded tape measure without injuring other students) Example sources for the hydrogen and solar cars: or search for the K NEX solar kit (more expensive but works very well) Procedure- Notes: This activity requires full and direct sunlight for the solar cars to work properly. The activity should be flexibly scheduled to allow for a day of full sunshine. Preparation: Pre-Activity: The cars may require assembly and testing. They come with detailed instructions on how to assemble and operate, and how to troubleshoot any issues. It may take some time to become familiar with their operation and how to troubleshoot issues in advance of this activity. Typically, the hydrogen generating stations require batteries and distilled water. A runway or series of runways should be set up in a suitable area outside in direct sunlight. Note that areas near buildings may develop shadows late in the day that require moving the runways. The runways should be marked with a start and finish line, a distance of feet is appropriate. The hydrogen cars will need a flat surface such as a desk for refueling. Each car should be checked for wheel alignment. Some cars may go out of alignment causing the vehicle to veer off the runway during the races. Students should be given background information about the technology or principles behind the operation of each type of car. This could take the form of a formal reading activity, a presentation or a computer based discovery

3 Activity: lesson. In lieu of this, the principles of hydrogen generation and photovoltaic operation can be demonstrated in a few minutes before the race activity using the cars as props. In groups of 2 5, students will race each type of car by timing the cars individually as they travel the runway. Multiple trials of each car can be made. Typically, one student is needed to time, one to start the vehicle, and additional students can stop the car, record the data, and rotate through to other duties when repeating the activity. Before starting, each group should measure the length of the runway from the start to the finish lines and record the distance on their data sheets. To improve accuracy and repeatability during the trials, each car is started or turned on in the air or behind the start line and then released by the student at the start line, rather than attempting to turn on the car at the start line to begin the trial. Multiple trials by each group, or data collection of other groups trials by all can provide a set of data for later analysis. Post-Activity: This activity provides the opportunity to have students collect and analyze real data. In one example (see attached data collection sheet), the students have collected data for four trials of each car. They can then determine the average time for each car, and using the measured distance, the average velocity of each car. In addition, students can compare the velocities determined by each group in the class, or between different classes. This can be especially meaningful for the solar car data if the activity is performed by classes at different times of the day, as the sun angle will impact the speed of the solar car.

4 Worksheets- NAME: Run 1 Run 2 Run 3 Run 4 Hydrogen Car Solar Car Average: Distance: ( ) ( ) Velocity: NAME: Run 1 Run 2 Run 3 Run 4 Hydrogen Car Solar Car Average: Distance: ( ) ( ) Velocity:

5 NAME: Alternative Energy Vehicle Activity Questions 1.) Which car was the fastest, and what do you think made it faster? 2.) What was a source of error in your data measurement, and how could you reduce it? 3.) List one advantage and one disadvantage of each car compared to an internal combustion engine car. 4.) What is the main factor limiting each alternative energy technology from use in real cars? 5.) If you were to pick one of the cars to make into a real car, which would you pick and why? 6.) Where does the energy used in (a) an internal combustion engine, (b) a hydrogen fuel cell car, (c) a solar car, and (d) an electric (battery powered) car come from? For each, is the energy source renewable?