Human Power to Electrical Power to Solar Power

Students love seeing the power they create when you are able to show it on an overhead projector

  This picture  shows 5th Grade Students in Olympia Washington on two bike generators converting their lunch to ENERGY!! And having a fantastic time!  Click on the image to see a full size shot of the classroom competition.

The discussion centers around how food in your stomach is converted to mechanical energy in the bike, which then goes to electrical energy which then goes to solar energy, which is then converted back to electrical energy, which then powers a small fan which is mechanical energy.    There is many avenues of discussion for this fun activity.  Some include graphing the different power output of each student, checking heart rate before and after and recording it, The kids LOVE IT!!

 The laptop computer in the picture is using the USB LabJACK U12 USB data acquisition box and a LabVIEW program that reads the data from the LabJACK and graphs / charts the voltage, current, and power real time as the students are pedaling the bike.   You can see more information about the LabVIEW power monitoring / graphing program by clicking here.

The computer is optional.  If you don't have one, you can just use each exercise bike connected to 3 spot lights in series.   Each spotlight is 34 Watts at 12 Volts.   Each bike puts out about 36 volts DC.  The 5th graders shine the spotlights onto a solar panel which drives a small fan.   The solar panel was provided by http://www.jatsgreenpower.com  The bikes also power fans that are mounted onto a box with a big tube.  When the fans turn on, the ball goes to the top of the tube.  They LOVE watching the ball go up and down while they pedal!  This was done with a 1st grade class, 5th grade class, and 7th grade class.

Below is a shot of two exercise bike pedal power bicycle generators at a middle school in Steilacoom Washington.   The top graph you see in red is voltage from a bike, the middle graph with blue data is current (Amps), and the 3rd graph in yellow is power.