Let me first say I have very limited solar power experience. I need a light for my goat barn and a light for a similar sized cabin.What is the cheapest simplest possibly expandable solution using battery, solar panel and a dc light.....what could I get from salvage? I do have a battery charger already (one with clamps). Anyone rotate car batteries on commute to work? 40 mile drive for us in the near future..... Your wisdom is appreciated!
You can use a 12volt car battery and a 12volt incandecent lamp (they look just like the lightbulbs you use in your house). They 12volt lamps will fit in an existing lamp socket if you have one in your barn. You can periodically charge the car battery or use a solar panel to keep it charged.
Look into boating or recreational vehicle lighting. There is LED lighting that uses very little power that might work for your application. Do a google search with a few key words and see what comes up.
If all you need is one light at the cabin and one at the barn, I think if it were me I'd just get a couple of camping lanterns. Cheap solar DC lighting, solar panels, systems are not too great, from what I've found. Car batteries don't usually hold up too well unless your needs are extremely limited. Deep cycle 12v batteries can be good though. A decent system to suppy bare bones electrical needs for a small cabin using strictly DC will start out around $500-600 including a battery. And 2 or 3 days without sun, you're SOL. Lots of info. out there on the net if you look around. Here's a link to a site selling some low-cost systems that might work: http://www.partsonsale.com/cabins.html
I think any solar panel you can get and LED's for lights. You might even find that doing the car battery switch out, the LED's would not draw enough to even bother with the solar. Kirk
I used a system of rotating batteries that I charged while farming with my small tractor. I powered my computer and printer via a rather inexpensive invertor. If you just need some lights, use compact 7 watt and or 13 watt compact florescents in task lighting situations. A battery would power a 7 watt one a long time. The cold will affect them some at start up, but even in my yard light the florescent compact works very well. Saves me a bundle over incandescent.
Why not just use a gas pressure lantern? You can probably find an old Coleman camping lantern at any yard sale or on ebay for next to nothing. A brand new dual fuel lantern at wally world is about $40. A single mantle lantern will put out about 150 cp (candle power) a double will go about 350cp. Once you have learned to use them, they are very easy to light and maintain. A gallon of unleaded regular gas cost about $1.50 and coleman white fuel (unadulterated gasoline) is about $2.25. As long as your goat barn and cabin are not airtight you should be fine. Check out http://www.oldtownyucca.com/coleman/collecting.htm for a whole bunch of information on Coleman lanterns. If you really want some light purchase a petromax lantern. A large petromax can belt out 500cp (400W). It is a dazzling amount of light but they prefer kerosene as a fuel source. I run both coleman and pertomax lanterns around my place. I run one every night when walking the dogs. I prefer them to flashlights as they produce much more light and are cheaper to run if you are using them every night.
Anytime your working with solar power, you need to know how much power you need and how much you can generate with the available sunlight. A simple solar light system would be a 12v solar panel feeding a simple battery charger connected to a good deep cycle battery. The battery is connect to the light. Depending on how much light (in watts) you need. A small system would run about $10/watt so for a 60 watt light, figure $600. A bit pricey for a single light. As your wattage goes up the price/watt comes down a little. If you just need a night light for the barn and dont need a real quality light then you might consider some of the solar patio light systems. Doesnt generate much more than anti-trip light but its pretty cheap. If you want to get serious about solar power, check out www.homepower.com
Bass Pro Shops shows a 12 volt solar battery charger for $29.95. That and a 12 volt lamp screwed into a brooder lamp and a deep cycle marine battery would get you started for around $100.00 Might just use a car battery depending on how much you plan to use it. Some of the clamp on style reflector lights have a switch built into the fixture so you can turn it on when you need it. 12-Volt Solar Battery Charger [http://www.basspro-shops.com/servle...d=5196&hvarTarget=search&cmCat=SearchResults]
You can get the panel at harbor freight for 39.99 on sale or 49.99 reg price and the inverter will cost another $70 or less. Deep cycle batteries are about $40 each. Two batteries, panel and inverter - - not the light - - $160. I did it.
