I have 20 solar panels on the roof, I’ve been wanting to do some experiments with tracking and temperature so I got 1 more solar panel to play with.
I’ve been way to busy to get far on that project, but in a few spare moments my dad and I slapped together this rig to hold the solar panel.
It has a hinge to adjust the angle for seasonal variation, and the panel is on an axle that lets it point at the sky for whatever time of day.
Of course, after we finished it, we realized what we did wrong and how to do it better – eventually I want to build an active tracking system and the geometry of this rig makes that hard.
But I had the wheels and lumber lying around so this is what we came up with:
I haven’t even had a chance to hook it up electrically yet, if I get a few spare moments I’ll try to do that this week.
Do you plan to track with astronomy software or sensors to determine the sun’s position? I can help with astronomy software if you want to go that route.
Passive tracking (movement driven by a liquid which expands and contracts with the sun’s heat) seems to be cheaper and more foolproof, but I’ve only seen designs for it offered from Australia…
My approach to the problem of single-axis PV panel tracking is a hybrid of polar axis (North-South orientation) with a seasonal elevation adjustment for each panel on the polar axis array. This has structural advantages when designing for wind loading because the horizontal cross-section is smaller and also in combating wind lift loading on the panels, which is too often underestimated by designers in my opinion and direct experience.
As a cost effective engineering problem this is becoming more of a challenge as raw PV panel prices have dropped below $0.95 on the Civic Solar Inc website recently (Aug 2012). There is less margin for the mechanical cost overhead to move panels thru the sun’s arc and gain only 30 – 35 % more harvested energy. Seasonal tilt can help as well as cooling the panels as documented on this fine website.
— mark early, Seattle