The need to (or not) carefully track the sun for solar

time2roll wrote:
Last I read you can about double the harvest with tracking.

Doubling? A 100% increase over doing nothing?

MEXICOWANDERER wrote:
Huge solar farms ignore tracking for a reason...

What reason?

Or there is the low-tech version -- I have a portable panel. In the early morning I point it to the east. As we leave the trailer for the day, I point it south. When we come home in the afternoon, I point it west. Not perfect, but better than nothing.

A good thing with a twirler (that is also tilting) is you can aim it at the sun in the morning and get your batteries done before it gets cloudy that afternoon. Or if it is misty all morning until it "burns off" and you get sun all afternoon you can aim it around to NW and get max AH haul instead of having it pointing South and missing a lot of afternoon sunshine.

Of course if you have the panels flat on the roof and enough panels to do your batts daily most days, you don't care.

A contraption for an RVer's panels to twirl and tilt is for when you don't have enough panels flat on the roof to get the needed AH haul.

Huge solar farms ignore tracking for a reason...

You have two things to track for.
1. the daily up and down and going around of the sun, and
2. the annual change in declination (angle of sun above/below Equator)

You also have an RV, so your latitude can change, which affects things. It is all here for how it works.

http://forums.trailerlife.com/index.cfm/fuseaction/thread/tid/25549683/srt/pa/pging/1/page/1.cfm

Last I read you can about double the harvest with tracking.

Do you have a place to store the energy? Typical lead-acid has such a long absorption time... maximizing the afternoon may not matter.

Moved to Tech Issues forum from DIY.

Thanks.

This was the kind of detail and guidance I was seeking. Obviously the roof-mount case is unworkable as I doubt any rig owners move their RVs to track the sun.

I may build a tracker just for the fun of it and ignore the costs since I had so much fun on my last DIY project.

unless it is very efficient, continual tracking may take more energy and work than it saves.

However, my idea of tracking is to find the optimal angle at near noon, set the panels for that, and let it go during the day. A quick and easy way to set for optimal angle is to take a empty TP tube, place it on the panel perpendicular and move the panel till there is no shadow.

Now this works fine for portable panels. roof mount another story.

And depending on season and location, even this may be overkill. closer to the equater you are the less angle from horizontal is needed and less loss vs. horizontal. Move above 50 degrees latitude, in the fall the drop from optimal angle to a horizontal panel is pretty noticeable. can be on the order of 30% loss or more.