Sun Tracking for Solar Panel

[freedom]

Hi I am about to embark on a Solar panel Tracking system so that I can track the Suns position (Azimuth and Altitude) using GPS and positional Data.

I know I will need a GPS Unit, I will need to also obtain exact Time + also obtain data on how off level the unit will be (it's on top of a mobile home) as well as absolute direction.

I have the basics of an algorithm for determining the Azimuth and altitude of the sun from GPS data fro here…
http://www.saao.ac.za/public-info/sun-m ... ate-altaz/

Then I need to work out my direction, and how off level the unit is.

Then I will power two stepper motors to position the panel, these may be attached to gearing to turn a turntable and also to raise and lower the panel.

This way the Solar Panel will track the sun when it is cloudy or what ever the weather.

Any suggestions most welcome.

[adafruit_support_bill]

Sounds like a great project!

The GPS will give you an accurate time. A compass module will get you the orientation and a multi-axis accelerometer will get you the leveling data.

[smindinvern]

I'm actually working on a similar project myself, though for a parabolic solar collector rather than a panel. If you have the budget to get a GPS module, you might want to consider just making it internet enabled, and grab time data over NTP and solar position data from a place like the US Naval Observatory. The compass is a good idea, depending on whether your mobile home will actually be mobile or not, but if not, you might just consider fixing the base in a known orientation to begin with so that it always knows in what direction the panel is orientated. Also, I can't imagine that it would be so off-level that it would affect the angle of incidence of the light hitting it too terribly much, so you might just consider taking that concern out of the equation. One thing that I've considered doing is just firmly fixing my contraption in a known position and then adding momentary switches in specific places to provide a sort of zero point, so that if the power goes out or something goes wrong, you have a zero index that the device can reset itself to. I'm not sure if your situation would permit something like that, but it would certainly be cheaper than a compass and accelerometer.

[CharlieD]

Have you considered just using an array of suitably shielded photo-sensors, and an algorithm which will 'search' for light-intensity peaks in both Az and Alt ? - This may be the simplest solution