# 100 watts lights all night with a junk car battery



## budgetprepp-n (Jul 8, 2015)

I took a security light and switched it over to a 12 volt LED light bulb. For power I used an old car battery
and to charge the battery I used a 100 watt panel. I used a 12 volt photocell switch to turn it on and off.
The battery is the same one I have been using for experments for years It sat out all winter and showed about 10 volts
it charged and seems to keep up. The bulb pulls less than 1 amp
so it doesn't take a lot of power to operate.

So the same bulb could be in your house for light when the electric is out

I put aluminum foil on the back side so it doesn't blind you at night if you are on the back porch.
Also you can see the photocell (little white box) 


I can't believe this battery still will hold any kind of charge it's been completely drained many times in the last
three years doing experiments. That voltage was with the panel charging it drops quick when the sun goes down


I unhook this 100 watt panel from my system and use it for experiments when I need solar power.
If you look close you can see the controller I use it's one of those $14 ones 


So for less than $150 and a junk battery you could have what you need for emergency lights
It will run all night and recharge during the day no problem. 
this battery drops to about 12.3 over night but I'm sure a good battery would do much better

I'm going to let this run for a few weeks and if no problem arise I'll wire it into my battery bank


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## cowboyhermit (Nov 10, 2012)

Current solar and led tech makes "off-grid" or emergency lighting something that anybody can do and afford. One full-sized panel and a good deep cycle battery coupled with some efficient leds can provide a remarkable amount of light, realistically more than anyone _needs_.

Old batteries coupled with a solar panel can be useful for a ridiculous amount of time. The solar panels are very good for them and as long as they are not actually shorted even really bad batteries can provide some reserve. I have some batteries that were written off years ago for starting anything, but coupled with a small panel have been running 12V fencers, electronics, pumps, etc for years.

Lately I have found a lot of reasonably priced components that run on DC and particularly 12V that can help with projects like this. Dead simple motion sensors;

















Motion sensors with a few more options;









Complete motion sensor lights at reasonable prices like these;









All available through Amazon, Ebay, etc. Many fun and useful projects to work on...


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## ZoomZoom (Dec 18, 2009)

I like the way you think and your creativity.

Call me lazy but why not just go buy a set of solar powered accent lights (like you put in the ground next to a walkway)? A set of 8 lights can be bought for $20-50. I have some and would just pull out of the ground and put them where needed for light if the power is out.


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## cowboyhermit (Nov 10, 2012)

ZoomZoom said:


> I like the way you think and your creativity.
> 
> Call me lazy but why not just go buy a set of solar powered accent lights (like you put in the ground next to a walkway)? A set of 8 lights can be bought for $20-50. I have some and would just pull out of the ground and put them where needed for light if the power is out.


The fact that solar powered "accent" type lights are cheap and easily available is great, they have already been used in emergencies. However, they do not produce a ton of light, they are not especially convenient, and they don't typically last for that many hours. So, it is a comparison of dim illumination that has to be moved around versus excellent lighting for reading, heart surgery, whatever. 

For a barebones setup, any old batteries that aren't shorted can be parked on a small solar panel that ($15-100) without a charge controller and hooked up to some 12V LEDs. Even for $100 a person could have some excellent lighting for a few hours per day, or minimal illumination for many. Without having to move things around all the time.

For an in between solution, I would go with something like a multi-purpose battery/booster pack with an inverter and even usb, that can be charged with a solar panel. Some have lights that come with, but I would pick up some really good LED lamps. So, for a couple hundred bucks a person could have excellent lighting for a room or two for many hours, essentially indefinitely. They would also have a way to charge anything they already owned, etc.


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