Steve, how many panels can you afford to run the fans ?? Why not use Radiator fans that are heat sensor controlled ?? Junkyards or "Auto Salvage yards"
should have a bunch. They run off of 12 v DC, so, a few batteries, and the panels to help offset the batteries, and, you are good to go.
I am about to embark on a system to make my own Solar Panels. I bought 500 watts of 6" X 6" Solar CELLS off Ebay, for $250.00, including everything needed to solder them together. Prices are cheaper, now, than what I paid. I will build 3 panels using 35 cells per panel, and get , on a GOOD day, 24 Amps of output at 12V, (actually 17.5volts output), but, able to put 24Amps into batteries.
I will use regular window glass, 1/8" thick, and I bought Solar Panel EVA to use to seal up the whole thing. Got it shipped into Fl. for free shipping.
Will pick all my stuff up in 3 weeks and bring back enough stuff for 5 projects.
There is a 3 part thread, over on
http://www.fieldlines.com, where a guy shows the whole deal from start to finish. He built a small oven to put the panels in, so he could melt the EVA and seal the panels. This is what the Pro's use to build panels. I think the average chimp can build these, so, I'm all over it. My panels will measure approx., 33" wide X 45" high. I will encase the glass into an Aluminum frame, and, hopefully, build a tracker to follow the sun.
My current Solar Kiln, gets plenty warm even on partly cloudy days here. I also put a 30 Pint Home Dehumidifier in there, and run it occasionally, to see how much water it will pull. I can dry lumber to 12% here, which is fine, in about 120 days. that's 3 loads a year, and, I don't do anything after I put the wood in there. I also do not use fans. The top of the kiln is not sealed up, so, I have heat losses, but, it also moves the moist air up and out. I really need to finish up the kiln, but, I don't NEED it, so, I just put nice stuff in there after air drying for 30 days, and forget about it, until I check with the dehumidifier.
When I built the kiln, I put down boards on the bottom of my 2 X 6 X 5' long joists, that made a boxed floor at 12' long X 5' wide. I then put sheet plastic into each "box" and piled in dry sawdust. Covered all that with a sheet of plastic and floored it with 1X lumber. (Nice to have a sawmill, ain't it),
, and covered THAT floor with a folded over sheet of plastic. Then, built 2 X 4 walls, and 2 X 4 roof, and filled plastic feed sacks with dry sawdust. Put them in the stud walls, and nailed up 6" X 6" concrete reinforcing screen, to hold the sacks in place. Same with the doors. You would be AMAZED at how hot it gets in there, so, I never finished the openings between the roof beams.
No one around my area dries wood, so, it settles in at around 14-16 percent, according to my Pin Moisture Tester. That's what all the houses are built with, other than cement blocks.
I bought a wireless thermometer system, and, it reads 100°+ any sunny day, with dry lumber in there, and the reading is transmitted through a stack of lumber I have inside the shop, on stickers for over a year. Humidity stays around 30% or so, but, I KNOW that reading is off, because of the open rafters and the lumber pile that blocks the accuracy of the sensors.
DaaAAAMMMMMMMMMM. This is a long post. BYE.