Sun Position Apps

2/5/15

Before I decided which vendor to use,  I wanted to get better information on the position of the sun throughout the year.  Both reps assured me that the roof location would be adequate, but I wanted to double check.  This site has some good information on figuring out the position of the sun throughout the year, but it was all manual.  I figured there had to be an app that could do what I wanted. Google’s app store had 2 free apps, Sun Surveyor Lite and Sun Position Demo.  I wanted an app with augmented reality. Augmented reality takes advantage of your phone (or tablet’s) camera, magnetometer, and GPS.  You point the camera at the sky and the app shows you the sun's path and where it will be during the day. You can see where the sun will be on any day, at any time.

Sun Surveyor’s Lite version does not have augmented reality.  You pay $6.49 for that feature.  Sun Position Demo had augmented reality, but only for the current date and time.  I loaded both apps on my old Acer tablet.

Sun Position gave me a hint of what augmented reality could do.   I could get it to work for about 5 seconds and then a message popped up telling me I needed to recalibrate.  To recalibrate a tablet’s magnetometer you wave it around in figure 8 patterns.  With Sun Position, I was doing this way too often for it to be of any use.

Sun Surveyor Lite has a dynamic map that shows you where the sun is for any date.  I didn't have any calibration issues and decided to make a leap of faith (based on reviews) and purchase the full app with the augmented reality.  I figured it was only $6.49 and if it didn't work, that wasn't much money lost especially if it gave me good information about the utility of the $5000 system I was planning to buy.  To make things even better, the app was also on the Amazon Appstore and I still had a bit of money left over from a gift card so I could get it for free.  I downloaded Sun Surveyor and went to work.  The app worked fine. I can see where the sun will be in the sky for any date and time.

I decided to climb up on the roof and make a table of sun position for the first of each month.  The table would show when the sunlight hit the roof and when the sunlight was no longer on the roof.

The readings taken from Sun Surveyor are very encouraging.  From March until October we should get 6 to 8 hours of sun.  December is the worst with only 4 - 5 hours.  It will be interesting to see how accurate my projections are.