I really like the idea of using an inexpensive micro-controller for this project. There are commercial solar tracking devices, but those are a lot more expensive and aren't nearly as satisfying as making your own. Check out the web site for a lot more information.
This is just the first part of my overall project idea which I will keep posting about as I progress further. I was able to power up my 65″ HD TV, cable box and Wii with the solar panel I am using by adding my scooter battery and an invertor. So I want to pursue some of this idea but make something that is more effecient. I am going to start keeping a better track of our energy bill each month, and see if I can bring it down. I wont be able to go of the grid just yet, but I think it will be interesting to experiment with.
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