Doug...

http://batterytender.com/products/solar.html

Oh, Man! Guess I've been living in the dark ages. Didn't know that was available.

Would it be possible to put the solar panel on the dash of the car, or elsewhere on the interior? Our street gets direct sunlight for most of the day.

I'm also assuming that a 5 amp panel would be enough to maintain a battery?

Yes on the dash, just needs to be in direct sunlight. I would go with at least the 10 watt panel Doug for a couple of reasons:

That one will put out 1/2 an amp whereas the other one id half of that, the standard tender junior is 3/4 amp.

As the panel heats up, which it will do inside a vehicle, it will output less power...a function of all solar panels.



You could also wire it directly into your cigarette lighter for less hassle.

Thank you, Duncan. I am electronically challenged. I said 5 amp, but I meant 5 watt.

I figured that

taxreliever said:

Duncan, I was jealous of home made lead and did this with the one that came with my tender temporarily so I can start not having to open my hood just to plug it in.

Click to expand...

Photobucket...dangit!

DNFXDLI said:

Doug...

http://batterytender.com/products/solar.html

Click to expand...

That's cool....I had no idea!

so you would not recommend something like this ?

http://www.harborfreight.com/15-watt-solar-battery-charger-68692.html



heck for $145.99 with coupon,, I may just get this...use it for camping....
solar panel sale

rambler said:

so you would not recommend something like this ?

http://www.harborfreight.com/15-watt-solar-battery-charger-68692.html



heck for $145.99 with coupon,, I may just get this...use it for camping....
solar panel sale

Click to expand...

Quite a difference in price, but there usually is with HF stuff.

rambler said:

so you would not recommend something like this ?

http://www.harborfreight.com/15-watt-solar-battery-charger-68692.html



heck for $145.99 with coupon,, I may just get this...use it for camping....
solar panel sale

Click to expand...

I wouldn't suggest that. There doesn't appear to be a charge controller on that small panel and 1.5 watts really won't do much at all.

The second one.....
OK...so 3 15 watt panels...45 watts total. No charge controller....so what that means is you will possibly be forcing a higher voltage through your batteries that what they can take....bulk charging is typically done at 14.4 volts....those panels will probably have an open circuit voltage of 20 or better volts which will drop off when loaded.
That is fine until your batteries are near a full charge...then the voltage will ramp up as the charge load drops...you can boil your batteries.

Real solar setups have the panels connected in a much higher voltage than what is required....reason for that?....panels output there maximum in unobstructed sun...as soon as that goes away the voltage drops off.

So....you take 3 panels rated at 24volts...tie them in series to yield 72 volts...then that goes through a bucking (reducing) converter that drops the voltage down to the proper level of charge voltage.

So when you have cloud (for example) the 3 panels still might be outputting 10 volts each...but when added up gives 30 volts and you are still able to charge your batteries.