panel angle

Novaz

Finally have my off grid land in Arizona at approx coords -109.21 / 34.837
I know there is a thread about panel angle but have been unable to find it
in Solar Energy Hand Book the author quoted several settings based on 90*-Latitude for a fixed setting or +/- 90* and 15.6* for winter and summer settings
then later in the book he has a month by month recommendation for angle
and finally he mentions using due south as opposed to just south is this correct
as a newbie still I want to start with an optimum array and then go by results
for my particular spot
Thanks
Roy

Mountain Don

Re: panel angle

This is just my opinion... I built our pole top mount to be very adjustable. Figured out all the best angles for each month of the year. Drilled holes for all the calculated angles. Stamped the months by the respective holes. That was 5 years ago. For the last couple of years, or maybe that is now three years, I make two adjustments per year. Once in the late spring or early summer to switch it to the summer setting and then once in late fall or early winter to move it back to the winter position. And I am beginning to think that is too much fiddling around for theoretical differences I can not really see. With the longer hours of summer sun I think I could leave it at the winter angle all year and still reach float every day.

gww1

Re: panel angle

Sorta like mounten don, I think my best winter tilt is about sixty degrees and I believe I ended up just a tiny bit west of south at 45 degree tilt. I used the satilite dish on my house to get close to south. I borrowed my dads tractor to dig the holes and was in a hurry and didn't have a compus. It is a fixed array . If it wasn't so hard to mess with I do wish I could tilt the panels to about 25 degree tilt in summer as the sun seems almost behind the aray. Over all while sitting on the couch and searching the computer I did stress some. I used pv watts and put all kind of angles and checked the expected prodution, but when it came time to do it, that all went away and I just wanted to get it done. I am not unhappy with the results and am pretty sure if I could move them I wouldn't unless it was as simple as pulling a switch and it happened for me. I only have one regret, I wish I would have added 2000 watts more while I was doing the spending and building cause it is working just good enough that I can't get enthused enough to take that one last step that would make it perfect. Before I spent any time or money on fancy tiltable racking, I would just build more fixed racking and get a few more panels. I am sure when solar was $5 per watt I might have wanted a tracker.

I am not saying I am correct in my veiw, just that it is my view. I get that view cause I am very lazy and it is nice just to see stuff work without me having to help it.
Good luck
gww

Ethan Brush

Re: panel angle

You may find this site useful:
http://www.solarpaneltilt.com

ramloui

Re: panel angle

It may be useful for you to noodle around with PVWatts (http://pvwatts.nrel.gov/index.php). Try different angles and compare the scenarios. Of course, for me, since I'm only using my cabin 5 months per year, I quickly abandoned the project of making the array angle adjustable. And my guess is that, as Mountain Don said, you will find out that you do not gain a whole lot, even in the perfect world of the PVWatts tool. Transposing that to real life, with all of the other stuff that cannot be controlled, It probably will not be worth the effort.

Plus, depending on how your array is set up (roof, top of pole...) it may save you an opportunity to get hurt.

Cheers!

Organic Farmer

Re: panel angle

http://solarelectricityhandbook.com/solar-angle-calculator.html

http://www.solarpoweristhefuture.com/how-to-figure-correct-angle-for-solar-panels.shtml

http://www.mysolarpannels.com/optimum-angle-for-solar-panels/




I did mine to use three angles. One for summer, one for winter and one for both spring and autumn.


Angles:
Summer - 21.7 degrees from horizontal
Spring / Autumn - 46.7 degrees from horizontal
Winter - 68.5 degrees from horizontal

littleharbor2

I found an app for my smart phone simply called "Solar Tilt" It uses GPS to give you the exact tilt for your array. It automatically gives you this info inc. your location. The cool thing is you can input any latitude and any day of the year and it gives you the exact tilt for that day. It also has a built in inclinometer so you just hold the phone on edge on the face of your panel(s) and it gives you the tilt angle and tells you when you are perfectly angled. Very easy to use. If you want a good average tilt for say mid spring/fall just input Oct. 7 or April 7 and you will know what is optimum tilt. Gotta love this technology.

Dave Angelini

Novaz wrote: »

Finally have my off grid land in Arizona at approx coords -109.21 / 34.837
I know there is a thread about panel angle but have been unable to find it
in Solar Energy Hand Book the author quoted several settings based on 90*-Latitude for a fixed setting or +/- 90* and 15.6* for winter and summer settings
then later in the book he has a month by month recommendation for angle
and finally he mentions using due south as opposed to just south is this correct
as a newbie still I want to start with an optimum array and then go by results
for my particular spot
Thanks
Roy

You may fine that you need cooling on your new land. Having 2 arrays that can adjust both altitude and azimuth will give you long hours off the battery. Good Luck!