Solar Roof

[Christ]

Any chance that you could just place the acrylic panel in a clear vacuum bag, then lay out your cells face down on it, and vacuum laminate them to the acrylic? That way, there would be no way for the capillary effect to take place, since there wouldn't be a gap between the cells and the acrylic.

Another option might be to slather petroleum jelly on the cells before placing the acrylic back on top (after drying it all out). No idea what reactions might occur, though.

[gascort]

Update - I replaced the acrylic (plexiglass) with 0.093 (inches??) thick Lexan polycarbonate. I sealed it with Lexel brand clear sealant that is designed to adhere to plastics, etc., and installed some 1/8" bar stock aluminum around the edges of the panel. I now have to lift my Kammback to meet the aluminum bar at the top of the rear and it's not quite as aero as it was, but no leaks after 3 weeks and several rains and long trips!!
I'll get off my butt and get photos soon. Going to a vehicle and transportation fair for little kids this weekend - hope the kids enjoy my car as much as the fire/trash trucks!

[Christ]

I was walking about the local Wally World tonite, and noticed that they now sell drip pans for working under cars.... Thinking about it, the drip pan is about the right size for a roof-replacement... it's also got a 1/4" depth or so to it, and a rolled edge that would allow it to sit not quite flush... too bad it's galvanized steel, best I could tell.

[Intrigued]

It's good to see you have gone with the good stuff (Lexan) The 1/8th inch thick Lexan that I used for my air dam extensions has been curbed/scraped/etc. a hundred times, and amazingly, hasn't even ripped out one of the screw holes yet!

...knock on wood...

[basslover911]

Have you hooked it up to the actual batteries to replenish them?

I want to do this so bad as I only drive my car 1-2 times per week and its ALWAYS sitting in the sun (college parking lot) so if I could possibly drive 20 miles a week on sun power alone... that would be GREAT... i would never have to buy gas again...

until I leave college lol.

[micondie]

The problem with polycarbonate is that is soft and scratches easily. I suspect that a continuous exposure to air flow will cause it to frost from the dust in the air. That would reduce the efficiency of your panels. Keep an eye on it and let us know.

[Christ]

Lexan scratches easily? Hm... never experienced that with my SpeedGlas windows. I was told those were Lexan as well.

[gascort]

Haven't noticed anything yet regarding the scratching, but will keep an eye out. Nothing compared to the 1+ liter of water that the plexiglas and silicone let in though! Whomever has ever claimed solar cells are fragile was full of it. I had those things baking in the sun and underwater for almost 2 weeks, cracked several in half due to driving to the store to buy the new sheet of lexan while they were uncovered and flapping around (found out neither my wife's car nor my mustang would hold a large enough piece AFTER I took the plexi piece off!!) and they still work pretty well. Not as well as they did, but took a pretty awful beating and I'm still at 85+% of their original performance.

I do have it connected to the car now; I have schotky diodes inline with the panels and have them connected via a cigarette lighter plug.
Still haven't worked out the alternatorless stuff for gains, but did have some nice benefit - I noticed yesterday that I left my power on to my wipers/blower motor for 2-3 days. Usually this would drain the battery pretty badly, and I'm sure the continuous (in daytime) 14.5V from the panels helped save my $160 battery.

[miket]

How many watts of solar panel are needed to run the blower to keep the car from getting hot?

[Daox]

The blower on my car takes ~60W at max speed.