Homebrew solar panels, half way there.

[Volvo farmer]

I got my frame welded up and my pads poured. I used 1x2" box and 2" angle to make the frame. My welding and my welder really suck but the steel is mostly stuck together and doesn't seem to be coming apart. I attached the frame to the pads yeaterday and hauled the first two panels out there today. Decided to mount the panels for optimum winter exposure, about 62 degrees from horizontal. I'd love to track these but they're just too dang big and heavy. From what I've read, They will put out 15% less in the summer at this angle, but I've got more power than I need then anyway.

So at about solar noon, I was getting almost 3A wired for 48V. Voc was about 68V, which worries me a little. I'm planning on sistering these to my BP SX170s and their VOC is more like 88V. I may end up just buying a C40 for this homebrew array and wiring it for 24V, but I think it will be interesting to see what happens connecting a fixed and a tracking array, through an MX60, with radically different Vocs.

Exciting things happen at 68V and 3A when you try and connect meter leads. Little arc-welding was going on between the wires and the leads.

Here's a shot of the front with the my homebrew tracker in the background.

Here's a shot from the rear. A couple cells on one of my 36 cell strings broke about 1/3 off the edge. The difference in power is noticeable, both in current and voltage. I ain't breaking these open again to fix it though.

Hoping to get another 400W or so out of these panels this winter. I'm not out of power yet but these days ain't getting any longer for a few months and I'm about even on production vs. consumption as it is.

[pepa]

hi valvofarmer, just a thought while looking at your nice panels, the commercial big boys rotate their panels on a floating platform in a round pond. with a little modification to your setup you could mount four wheelboro wheels and a central pivot to your unit and make a tracker out of it by driving one of the wheels with a dc motor and tracking system. just thinking about something to handle the heavy panels. anyway, looks good, pepa.

[stephent]

Lot of angle iron and glass there--now I see the 12" sonotube requirement.

Puts it in perspective to see it on them.

How much does each panel weight? Looks like a back killer.

[scottsAI]

How deep does the snow get?

Not sure the panels are up high enough from the ground. If snow on the bottom edge of the panel the output of the panel will drop or stop. Depends on internal diodes and voltage. IF none, then ONE cell shaded will cause entire panel output to zero.

When cold use a mirror to double the sun to panel, to get that extra boost when needed. DO NOT do this when it's warm out. Panel overheating will be the result.

Watch the panel temp if you chose to try this out.

A Large mirror cost much less than a solar panel.

Let us know how it works out.

Have fun,

Scott.

[commanda]

If you made a couple of those joints with nuts and bolts (hinged) and put a few extra holes down the back on the support arms, you could easily change the angle to suit the seasons. A small job once every 6 months.

Amanda