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Build Your Own Helio Tracker—a Self-powered Mechanical Sunflower that Turns with the Sun

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Areas of Science
Time Required
Very Long (1+ months)
Experience designing and building mechanical devices is preferred, or at least the willingness to invest many hours designing, testing, and re-designing.
Material Availability
You will need a photovoltaic panel, approximately 200 square cm.
Average ($50 - $100)
No issues

Jonathon T. Ota.

This science fair project was inspired by the following science fair project, presented at the 2009 California State Science Fair:

*Note: For this science project you will need to develop your own experimental procedure. Use the information in the summary tab as a starting place. If you would like to discuss your ideas or need help troubleshooting, use the Ask An Expert forum. Our Experts won't do the work for you, but they will make suggestions and offer guidance if you come to them with specific questions.

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The amount of energy produced by most photovoltaic (solar) panels is limited, due to their immobility. However, when photovoltaic panels track the movement of the Sun, their efficiency increases significantly. This can be done with computers and sophisticated electronics, but for rural or wilderness settings, a "low-tech" sun tracker would be beneficial. A solution exists in nature: the sunflower. The challenge in this science fair project is to design and build a device that imitates the sunflower's ability to continually turn its face toward the Sun. Like the sunflower, your device should not rely on any form of electronics. One way to approach this problem was described by Jonathan T. Ota in his project, Helio Tracker, presented at the 2009 California State Science Fair (CSSF). In Jonathan's design, a parabolic mirror focuses light on a central bottle, shown in Figure 1.

Large flower shaped devices with mirrored petals attach to an upright metal pole

Figure 1. Helio tracker.

Within the bottle, alcohol absorbs heat and undergoes a phase change to create pressure. The pressure moves through lengths of tubing to one or more pistons. The movement of the pistons causes the face of the "flower" to turn toward the light. You can read about Jonathon's results at the CSSF website. If you like to build things and find this challenging science fair project intriguing, get started building your own helio tracker.

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MLA Style

Science Buddies Staff. "Build Your Own Helio Tracker—a Self-powered Mechanical Sunflower that Turns with the Sun." Science Buddies, 28 Jan. 2022, https://www.sciencebuddies.org/science-fair-projects/project-ideas/ApMech_p045/mechanical-engineering/build-a-mechanical-sunflower-that-turns-with-the-sun. Accessed 28 May 2023.

APA Style

Science Buddies Staff. (2022, January 28). Build Your Own Helio Tracker—a Self-powered Mechanical Sunflower that Turns with the Sun. Retrieved from https://www.sciencebuddies.org/science-fair-projects/project-ideas/ApMech_p045/mechanical-engineering/build-a-mechanical-sunflower-that-turns-with-the-sun

Last edit date: 2022-01-28
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