Warm air intake

[Magician]

Well, if I see too much drop, I may just open the back and let the sun in while parked at work in our private lot. That hatchback is ideal for this with the tailgate that drops down. I'll just make sure I have a cable and lock to secure it just in case someone feels they need it more than I do.

[oil pan 4]

Also all manufacturers tens to use very optimistic ratings and that panels wattage rated based on voltage at 17 to 19 volts.
12v panels actually make 20 to 22 open current volts and their watts are rated based on production voltage which is usually around 17 volts for a 12v panel.
All those extra volts making up those watts you thought you had are actually just waste heat.
That's why you need a charge controler.
See http://ecomodder.com/wiki/index.php/Solar_12v_assist

[stovie]

Originally Posted by Stubby79

float voltage (13.8v) can be maintained indefinitely. That's what they keep SLA's at in backup lights/power supplies. It's what your alternator and plug-in chargers drop down to after the initial ~14.4v bump.

Awesome!! I was thinking of taking my white s10 and putting some deep blue racing strips down the hood and aero bed cover I plan on making and put strips of solar cells over that!!(so the cells don't look like **** by themselves!!) I figured I could get about 25-30 amps that way!!

[oil pan 4]

When solar cells lay flat you get about half their rated out put.

[Magician]

Well... my mpguino shows my battery typically is at 12.6 to 12.8 volts most of the time. I checked with 2 of my test meters and they show the same readings. I even checked 2 other cars in my household that tested at 12.6 volts. So, I will assume 12.7 volts give or take a tenth is a fully charged battery. Now we can do some testing over the next few weeks.
BTW..these readings are when the car is off.

[Magician]

Well, max charge certainly is affected by the weather... I've seen it as high as 13V on warmer days. The Solar Panel certainly charges at a higher rate in direct sunlight, so I simply open the hatch up in the back and park the car so the panel faces the sun throughout most of the day. I have a cable and lock running thru it, so fairly safe in my driveway during the day and my work has security in our parking lot.

I also put in a few switches to turn off my alternator... testing phase right now. I'll keep you posted, but I suspect the 13 Watt Panel will keep everything topped of since most of my commutes are under 10 miles. Panel charges all day when I'm at work. In a pinch, I can always turn it back on

I wonder if the switch is okay to turn back on while the car is on...?

Also got my LED headlights installed today... 36W combined... way lower than the 110W combined stock bulbs.

[teoman]

Its not really about the miles but the time. My commute is 15 miles which takes an hour by car.

[Magician]

Well, I drove about 15 miles with my alternator switched off and my battery voltage hardly changed at all... I then pulled off the belt and drove another 25 with not much more change... my little VX must not use much power when running. Overall dropped from 13 v to about 12.7 from quite a bit of driving. Promising results so far and will have to see if it gets charged back up to 13v while I'm at work tomorrow.

[teoman]

Nice to hear.

[Stubby79]

If it's anything like a Metro, you're only using about 5 amps to keep the car running. Depending on the size of your battery, that can take quite a while to drain it.