A Low-Tech Innovation Uses The Sun's Heat To Boost Solar Efficiency

Instead of installing an expensive motor, former Princeton student (and current Thiel Fellow) Eden Full is making a simple part that expands with heat, automatically moving a panel to its most electricty-generating position.

Think big, we tell aspiring scientists. Sometimes they should just think simple.

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.

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]

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  • Thecloudwalkingowl

    Is this real?  Or vapour ware?  Has the math been done?  Is there a working model that has been tested under real conditions?  This sounds great, but I've seen stuff like this being promoted that was not much more than a pipe dream.   I'd have really liked to see a picture and some math going on here.

  • Thecloudwalkingowl

    Since the site doesn't seem to allow me to respond directly to Mathew, I'll respond here.  

    Yes, bimetallic controls exist.  The question is whether or not they have been used to track the sun on solar reflectors.  Whether or not it is vapour ware is a significant issue.  People have to decide where we, as a society, are going to allocate our scarce resources.  There is a very vociferous industry devoted to "positive think" that is telling people that there is a technological solution to all of our problems---therefore we need never try to get people to change the way they live their lives. 

    If no math has been done, no prototype created, not testing in real-world conditions----IT IS BULLSHIT!!!!   I don't want the environment and human future at the mercy of crap artists.  All I'm asking for is some evidence that these things actually exist and some numbers that describe their real effectiveness.  


  • Mathew

    Awesome project!  Whether or not this product turns out to be vaporware, the concept of using differential thermal expansion for solar tracking is not new and is field proven.
    Steve Baer's Zomeworks has been selling the Track Rack since the mid-80's that works on a similar principle, only it uses a shifting refrigerant gas rather than a bimetallic structure. Bimetallic controls have been used in thermostats and thermostatically controlled water valves for decades (centuries?) and are proven reliable.