One teenager recently made a discovery that could help make solar energy far more efficient and affordable for the developing world with little more than two strips of different metals, some clever mechanical engineering, and a few years of persistence. Her $10 device will allow solar panels to track the sun almost anywhere in the world, without the use of electric motors

Eden Full, a student at Princeton, was frustrated that much of the sun’s potential to generate electricity was lost as the sun moved across the sky and away from panels. Electric motors could fix that problem by moving the panels along with the sun–but at a cost of hundreds of dollars each, if electricity was available. That means many poor and remote areas weren’t going to have sun-tracking panels any time soon.

The panels naturally move to maximize efficiency by following the sun.

Instead, Full developed an inexpensive device from everyday materials to move solar panels with the sun, and no electric motors. Her SunSaluter, constructed of cheap and recyclable materials, fits aluminum and steel strips to brackets holding the solar arrays. As the metal heats up, differential expansion rate means the panels naturally move to maximize efficiency by following the sun. The innovation can boost energy output by about 40%, according to Full.

Although young, Full was not an overnight success; she’s been thinking about these problems for some time. “Since I was nine years old, I have been doing solar panel-related research projects that gradually developed my interest and knowledge of renewable energy technologies,” Full said in an interview with GEnV campaigns.

Now Full is one of the 20-under-20 Fellows, sponsored by Facebook investor Peter Thiel’s foundation, which awards $100,000 to 24 young innovators provided they drop out of school for at least two years. Full is running Roseicollis Technologies, a solar energy startup, that will market her technology in developed and emerging markets. It’s currently deployed in two 1,000-person Kenyan villages. When it comes to the future of SunSaluter, Full–and her panels–will be following the sun.

[Hat tip: CleanTechnica.com]