My objective was to be able to charge and use, cell phones, tablets, laptops, and other devices that use less than 100 watts. Also I wanted to have the power ready and available day or night.
The parts I used are:
$39 Solar Cells Untabbed 0.5 volt 2.8 amp 1.4 watt
$11 CMP12 10 amp Charge Controller
$22 Chrome Battery SLA 10.5 Amp
$5 Old Picture Frame to encase the solar Cells
$8 Wood to build the frame to hold the panel
$4 Wood to build the Charge Station
$4 12 Volt Socket
$1 9 volt Battery To power the LCD voltmeter
$5 LCD Voltmeter
Things I had around the house:
Exterior Grade Wire 2 Conductor
Wire and Panel Mount Connectors
Fuses and Fuse Holders
150 watt 12 volt car Inverter
15 amp Blocking Diode
Step 1: Panel Construction
Tab the Cells and check the output of each cell before you solder them to each other, If you need help or need more information on how to do this use Google search and Youtube Videos. I used the backing for the picture frame as a layout and soldered them accordingly. Then I reassembled the picture frame with the wires coming out of a hole at the back. As soon as put it together I checked the voltage and amperage output and made sure that everything was connected correctly. 2 of the 40 cells I was sent had a much lower output so I did not use them in the final panel. I added the blocking 15 amp diode to the outside because it would not fit inside the frame along with a terminal block on the back. After everything was checked I sealed the panel with caulking and painted it.
Step 2: Stand Construction
The stand is nice and simple and the panel is also easy to remove if needed. I used metal clips that grab the frame tightly and used some pavers to keep it off the ground. I also used some bricks to weigh it down. The wire goes down about 6 inches into the ground and comes up by the house. Remember you lose dc current when traveling long distances, so keep the wire as short as possible. I'am losing about 50ma with the wire I used. My panel makes a little over 3 amps @ 19 volts, So less than %1.7 is lost.
Step 3: Running the Wire to Inside the House
I wanted to run the solar panel power connection into the house for convenience so I could diagnose or try different setups from inside the house. Also the temperature extremes hot and cold outside would have shortened the life of the battery at the very least if not of the controller as well. I checked for studs and conduit in the wall the best I could and drilled a small pilot hole. once i was sure there was nothing in the way I drilled completely through. I used a dc panel mount connector and a blank outlet cover to finish it up
Step 4: The Controller Setup
I wanted something portable that could be used anywhere once charged up. So i built a little stand that also holds the battery,controller,12 volt socket, fuses and voltmeter. The controller prevents overcharging or draining and keeps the battery topped off as long as its plugged into the panel connection on the wall. I used a 8 amp fuse on the load side of the 10 amp controller so I don't have to worry about pulling too much through it. I also put a 8 amp fuse on the battery just in case. The 9 volt battery powers the LCD voltmeter and it measures the voltage on the battery. Its a really simple setup and so far its been great. I have used it with a 150 watt car inverter running a laptop with no battery in it for over 6 hours with no problems. I have also charged up multiple tablets at once using the same inverter. I have yet to see less than 11 volts on the meter, it seems like its always ready to go. I will be using this for all of my charging needs.
Grand Prize in the
Spring's Coming Contest