I'd like to get into solar power on a very small scale. My chicken coop is not electrified, so to add light for better winter production, we have to run an extension cord out there. It's a less than ideal solution. I was thinking that being able to run one of the new LED bulbs for a couple of hours in the winter would be a low-draw way to get this done. I've seen 7w/40w equivalent LED's in a few places, and I was thinking about using something that bright or a little brighter.
The coop is in a semi-shady area even with the leaves off the trees, so power production would be less than ideal on a panel surface area basis.
I figure that if I can capture 75 to 100 watt/hours of electricity, I can get through normal days using 25 or so watt/hours (accounting for inefficiency losses, etc.) and have a little extra in case of rain/clouds. I would have this on a light timer so I could set it and forget it, to a great extent.
Being able to buy a system to do this out-of-the-box would be great for me, because I am just getting a knowledge base in the area of inverters, batteries, and the like.
Do they sell low-capacity complete setups on Amazon? ;)
Any advice, especially from folks who have done something like this before, would be welcome. I appreciate it.

Christmas lights



garden walk way lights..

For your application I'd skip the inverter all together and run 12VDC lights. LED 1141s in RV-type fixtures draw minimal power. Random bulb I got on eBay draws 0.13 amps @ 12V nominal. That's about 1.6W. Not quite as bright as a 7W LED bulb in a 120VAC lamp, but plenty bright for a chicken coop. Two or three of these would be far more efficient than a 120V system.

Inverters draw power all the time. I keep my 400W inverter on all day, everyday. It draws an average 16.4 Ah/day @ 12V. That's about 8 to 9W just for the inverter.

AC timers also draw power. I just tested mine, draws about 2W on its own. That would also be a 24/7/365 load.

So we're talking a continuous load of >10W just to run the inverter and timer before you even start powering that 7W light for a few hours a day.

If you ran two 1141 LEDs for 12 hours per day, they'd draw around 3.1 Ah @ 12V. You'd need a 12V timer like this. I use one of these to power a 12V fan in a cargo trailer, nice little unit. It draws about 0.09 amps @ 12V.

So say a total of 5.3 Ah/day @ 12V to run a couple RV lights and a timer.

A little 18 Ah wheelchair battery like this would be fine for this application. To charge a 18 Ah battery at a 10% rate, you'd need about 33 Watts of solar panel with no shade. How shady is your location? Is it constant dappled shade or are there hours of full sun?

I'd consider a Renogy 50W panel and one of Morningstar's small charge controllers (like this one).

This would be a pretty easy system to build by yourself if you have some electrical experience. If not, it would be a great beginner's project.

Or you could skip the solar all together and just swap out wheelchair batteries as needed. Be a lot easier and cheaper, but not as fun :)

Cathan91-
Thanks for the awesome reply.
I had not even thought of a 12 volt system, did not know that inverters draw power constantly, and am an electrical beginner.
The area would probably be between 50 and 30 % sunlight during daylight depending on the time of the year. Looks like I have some research to do....

I don't have any chicken raising experience so I don't know how much light is needed
I recently put one of these in my 7x7 shed and it is fairly bright, one of the reviews says they use it for a chicken coop
http://www.amazon.com/Gold-Stars-F3528001-Fixture-Natural/dp/B00CZCY5SE/ref=cm_rdp_product
review mentioning chickens http://www.amazon.com/gp/review/RD2TI8ACZHE7V/ref=cm_cr_pr_rvw_ttl?ASIN=B00CZCY5SE

I have it hooked to a 10AH 12v battery with a 7W solar panel to charge it. My first solar set up and limited research so that charging set up might not be proper. I'm not planning on using the light that much so I figure it should work though. I just got the panel hooked up yesterday so I don't have enough usage to say one way or the other on if it's going to work long term. The battery already had a charge when I got it so I've run the light for a bit already and am happy with the brightness for lighting the shed

LED Lights
http://www.amazon.com/SUPERNIGHT-Waterproof-Flexible-Strip-Ribbon/dp/B00BH91W9G/ref=sr_1_2?ie=UTF8&qid=1413755844&sr=8-2&keywords=white+led+reel

Charge controller
http://www.amazon.com/dp/B00NZJX5L4/ref=twister_B00LGIYMLI

Solar Panel
http://www.amazon.com/ALEKO%C2%AE-LM109-20-Watt-Polycrystalline-Solar/dp/B00KM94ADC/ref=sr_1_2?ie=UTF8&qid=1413756175&sr=8-2&keywords=20w+solar+panel

Battery
http://www.amazon.com/UPG-Battery-12V-20AH-Battery/dp/B005J50SRG/ref=sr_1_1?ie=UTF8&qid=1413756266&sr=8-1&keywords=20ah+battery

Switch w/ dimmer (Or just use an automotive switch)
http://www.amazon.com/Vktech-Modulator-Brightness-Adjustable-Control/dp/B00BX9GEP2/ref=sr_1_4?ie=UTF8&qid=1413756364&sr=8-4&keywords=Led+Light+Lamp+Strip+Dimmer+Switch+Brightness+Adjustable+Control+12-24V+8A

That panel-battery combo will result in about a 5% charge rate in full sun conditions. Too little for daily use, and far too little for partially shaded conditions. You want a charge rate in the 10-13% range for daily use.

Not sure what role the dimmer would play, the OP wants a timer, presumably to stimulate the chickens into laying more eggs by increasing their "day" length. I don't think a lot of light is needed for this, those 12V Christmas lights you linked to might work. Draw is 0.6 A, which is a fair bit compared to 1141 LEDs.

12V is what you want. You can add a small inverter (say 150W or less) to run other loads and keep it turned off when not in use. But considering your shade conditions, I doubt there'd be much extra power available.

If I were you, I'd get a couple wheelchair batteries and a smart charger like this. Get the lights and battery set up, then add solar later. Chances are you'll need a plug-in charger anyways, especially in winter.

This is not a difficult project, I'm sure you can figure it out :)

50W panel on a simple 2x4 mount + charge controller + battery + timer + 12V lights. Could probably use #14 wire for everything depending on the length of your runs. Add a couple in-line blade fuses for circuit protection on the wires between the CC and battery, and between the battery and lights. Maybe a cheapo voltmeter from eBay so you can keep track of battery state of charge.

If you know how to use a stripper/crimper, you have the skills to build this system. If not, 5 minutes on Youtube should teach you how.

Here is how I did it:



http://www.ar15.com/forums/t_10_19/671269_Solar_Battery_Coop_light_build.html



Ironically, I just turned it back on yesterday