How to Build a Solar Powered Car for School

Solar panels convert sun energy into electricity, which runs your car's motor.

Renewable energy sources, such as solar power, cut down the reliance on fossil fuels, which endanger people's health and destroy an environmental legacy of clean air and water, according to the Union of Concerned Scientists. Building a solar-powered car for school can spark dialogue among the younger generation that exposes them to the energy alternatives of their future. The design process lets students experience dynamic problem solving as they test and troubleshoot their solar-powered car.

Things You'll Need

• 1 DC hobby motor
• 1 plastic gear set
• 1 hobby tire and axle set
• 4 screw eyes
• 1 hobby solar panel
• 1 sheet of rigid insulation foam, 1/2-inch thick
• Hot glue or instant glue
• Scissors
• Craft knife
• Screws
• Screwdriver
• Rubber bands
• Alligator clip wires
• Electrical tape

Instructions

1. Cut a piece of insulation foam about the size of your solar panel. Cut four 1/4-inch-thick strips, two the length of the base and two the width. Glue the strips around the edge of the base to form a rim, trimming ends as needed to make a secure, unbroken fit all the way around.

2. Insert the larger of your chosen gears onto one axle and slide it to the center. Slide the smaller gear onto the motor arm. Twist the screw eyes on the underside, exactly opposite each other near the vehicle's front and back. Thread axles through the screw eyes and make certain they lie square with the frame and parallel to each other. Adjust placement as necessary and secure with hot glue or instant glue. Slide a wheel on both ends of each axle.

3. Take note of the location of the axle gear and cut an insertion space out of the base that allows you to mount the motor on the top side such that the gear teeth can fit together firmly to turn one another and the axle.

4. Connect the wires on the motor to the wires on the solar panel by twisting the ends together or using alligator clips. Set in the sunlight to collect energy for a few hours and then give it a test run.

Tips & Warnings

• Use a DC motor model that operates efficiently at low voltage. Check the rpm-to-voltage specs and get one that runs between 1,400 and 4,500 RPM at 0.5 to 1.5 volts, or more depending on the requirements of your solar panel. Check at stores and websites specializing in hobbies, electronics, robots and scientific supplies. A scrap recycling store is another option.

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• Experiment with different gear sizes and ratios to see which one produces the best speed results with your design.

• If the frame is not supporting the weight of the solar panel, add crossbeam supports.

• Try other materials such as a lightweight wood, corrugated cardboard, milk cartons or cardboard tubes. Experiment to find the sweet spot between a good weight and weight distribution for speed, stability and aerodynamics.

• You can paint your insulation foam vehicle but test the paint on a scrap first as National Renewable Energy Laboratory warns that some paints melt foam.

References

• National Renewable Energy Laboratory: An Introduction to Building a Model Solar Car
• California Solar Center: Solar Race Car Model
• Texas State Energy Conservation Office: Solar and Electric Cars
• Union of Concerned Scientists: Why Is Renewable Energy Important

Resources

• Winston Solar: How to Build a Solar Car
• The Green Optimistic: How to Build a Solar Powered Car for Your Kids