Battery / Charge Controller / LED selection.

Controller and battery will cost you more than a $20, 120V 3watt LED porch light.

Thanks for the info Mike. Can I use a 20W 12V LED instead? Can you please explain the math involved? Also what AH battery to go for.

10 watts minimum at 16.24 volts means 10w/16.24V=.61 amps minimum at 16.24V. Where did you get the 1.23A from?

Sorry, that was an arithmetic error.

No you cannot use 20 watt 12 volt LED and expect to power it with a 10 watt panel. Under the best conditions with the panel exposed to full sun light from sun up to sun set will only generate around 20 watt hours in winter and up around 40-50 watt hours in July. So if you want to burn a LED for 8 hours means the largest LED is going to be 20 wh / 8 hours = 2.5 watts. You would come out way ahead to go to Agent Orange (Home Depot) and buy a single 9.5 Watt LED bulb for $10 and use 120 volts socket. Would be a lot less expensive to buy and operate without any time limitations.

About all a 10 watt panel is good for is charging up a cell phone and would do a poor job of it as it could take a couple of days to do that.

here's a very bright, 12V 2watt LED

LED's for different projects (also in Warm white) They are VERY bright, only 2.2 watts and
have a integral driver module that powers them from 8-30V AC or DC.

But to use it with a 10w panel, you need a 12V motion sensor to reduce the ON time to something the PV & battery can handle.

Battery - since you barely have half an amp to charge with, a 5 Ah AGM would be about the only thing you can use reasonably. And then you need a charge controller, which would be another $50. The controller needs to be compatible with the battery chemistry (AGM).

So here is how it breaks down. With a 10 watt panel Free
12 volt 5 to 7 AH battery = $12
Two watt LED with driver = $8 with shipping
Charge controller = $30
Total = $50

A 12 volt 5 AH AGM (60 watt hours) used with this LED that consumes 3 watts burned 8 hours per night = 24 watt hours. LED emits 160 Lumens. Battery might last 2 years if you are lucky. Factor in the life of the product you will use it for 6 years, Operating cost = $12.30/year

Or

Order a Cree 60 watt equivalent here for $10 that emits 800 Lumens and burns 10 watt on 120 VAC. With a Electric rate of 12-cents per Kwh over the same 6 years brings yearly operating cost down to $5.20/year

So which is better?

A dim 160 Lumen light operating off solar that cost $12.30 per year to operate and will have several nights with no light due to cloudy days and regular maintenance, or a trouble free light 5 times brighter for $5.20/year.

I call that a No Brainer.

I'm going against the grain here...

digsolar found a panel and wants to use it.

Search "2 pcs - SOLAR - BATTERY CHARGE CONTROL 12 VOLT 1 AMP LED LIGHTING DUSK - DAWN" on ebay.
that charge controller is perfect for your needs, with dusk-to-dawn light control... it will turn the light on at night and off during the day.

So that reduces the projected cost from $60... and equips you to accomplish your goal.
Make absolute sure the panel is facing south.

Also, purchase a
"New LED Tube Light Bar 7W 12V 36LED 580LM Pure White Light Energy Saving" from ebay.

It is a 36 LED strip.
Cut it down to just 6LED.
It will burn only 1.5watts and put out about 95lumens.

I've done that on a few occasions.

Custom 6LED Housing.jpg 0125041606.jpg

You don't need to make a housing, just 2way tape the strip to the ceiling of your porch.

Using that 6LED strip 13hour nights, along with your 10w panel, for good health you will need an 8ah battery and 4 hour minimum insloation....