Solar Weight-Lifter: an Activity That Demonstrates How Solar Panels Work in a Easy to Make, Hands-on Approach

Different light sources emit different amounts of radiant energy, but this isn’t always easy to see. Make this visible by creating a solar weight-lifter! This activity converts light energy into mechanical energy in order to lift weight, showing a concrete measurable difference between the light sources. Which light source can lift the most weight?

More in-depth instruction can be found in a free educational guide here.

• high torque motor (2mm driveshaft)
• different light sources (incandescent, fluorescent, LED, sun)
• 3V solar panel*
• string
• cup (with two holes drilled around the top, so string can be threaded through)
• screw hub*
• weight (washers)
• duct tape

*these parts can be found (the panel is $12 and the screw hubs are 5 for $5) at the REcharge Labs online store, but another solar panel or a DIY screw hub is also an option!

Tie the string onto the cup and tie the other end onto the screw hub, leaving about a foot of length in between.

Attach the screw hub to the motor. Connect the 3V solar panel to the motor.

Securely attach the motor to a table with duct tape, allowing the string to hang freely off the side.

At the first light source, place the solar panel directly facing the light, positioning it 1 cm from the light source. (If using the sun as the light source, distance will not be a factor.) Measure how much weight can be put into the cup, while still allowing the string to lift the cup all the way up to the motor.

Repeat with different light sources. Which light source can list the most weight?

For more ideas, see the free educational plan: http://www.rechargelabs.org/solar-lifter