Thirteen-year-old Maanasa Mendu was watching tree branches sway in the wind when she noticed that the movement looked like piezoelectric materials – tiny devices that generate power through vibration. The insight helped inspire her design for a new type of renewable energy gadget. A prototype of the device, with three “leaves” made of recycled materials, cost $5 to produce. In an earlier version of the design, she focused on wind energy; but the later thought made her design adaptable to many other untapped nature resources: “Whereas if it relies on multiple environmental conditions – like sunlight intensity, wind speed, precipitation – all of these factors could create a more stable power source with a higher power output.”

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This Ninth Grader Invented A Cheap Device That Harvests Power From Wind, Sun, And Rain