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Panel positioning?

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juiced:
Should panels lie long facing the south sun (more hours of low input?), or stand tall all day?( Short, higher input?)
  Ideally, you have enough panels not to worry; but for starters....
 Also i know that there is a longitude caculation for angle; but i am curious if anyone knows of a chart to figure out effectiveness in variable situations, ie 90* , 0*, 60* etc...

jimovonz:
Check out this post for lots of information (including panel positioning/orientation) specific to your area:
http://www.fieldlines.com/story/2004/10/6/164945/703
Generally your panels should face as close as practical to due south (north in southern hemisphere) and should be more vertical in winter/more horizontal in summer. How much depends on your latitude. The orientation figures you get from the above link assume a flat surface that absorbs energy equally from any incident angle. Glass covered cells reflect much of the energy at low incident angles so I would mount my panels 5-10 degrees more vertical than is indicated from the data on this site.

You can also get an idea of your total daily output at different times of the year for different panel inclinations from the data on this site. The daily energy figures in kWh are per sq meter. So measure your panels and assume a panel efficiency of 10-15%.

Tyler883:
I've never tried this, but here's an idea:
If you've got a multimeter that will show you the output voltage of your solar cells while still showing you differences in voltages in the tenth or thousandth of a volt...You might try optimizing your inclination for maximum voltage on your volt meter.
I like this idea better than using a chart, because if you stick to real world results you aren't leaving yourself vulnerable to  unexpected error that the charts haven't calculated for.
cheers
Tyler

wpowokal:
Homepower published an artical on tracking sola panels in their last issue, this may help. Go to their site, register and read on line.

http://www.homepower.com

regards Allan

ghurd:
Lie long. Stand tall. ?

Are you asking short side up or long side up? The panel doesn't care.

The Junction box might, the instructions should say.

I mount them long side up. Makes for less material in the brackets. Maybe a little less leverage for the blowing wind.

I get asked that every week, like if its tipped the electric will pour out easier.
Mount them South facing, at about 10' steeper than your latitude.  This will give a little less in summer, but a little more in winter when you need a little more.
For adjustable brackets. Spring and fall at your latatude X, winter X+10, summer X-10. I read adustable brackets, done everyday, will only increase the output for the year about 15%. I never figured it was worth adjustable brackets, and just throw another $100 at the panel, so it won't need adjusted 4 times a year(idiot-proof).
I'm not big on trackers until you have a BIG PV system. Expensive and breakable. I mean, if you are putting up 200w and a tracker, its cheaper and easier and more output to put up 300w fixed.
What you want is the biggest shadow from the PV.  The bigger the shadow, the more sun it is catching. Close is good.

Hold you hand flat under a desk lamp, 12" up from the desk. Tip your hand both ways 15'. Not much change in the shadow. Now hold it verticial and tip it both ways 15'. Big change in the shadow. Thats degrees, not feet.
If it snows up there (lol), mount them where you can get the snow off with a broom.

A quarter inch of snow will shut them down. If they are on the roof of a 3 story house, nobody wants to go up in the snow to brush them off.
G-

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