I had a solar panel laying around along with a charge regulator and a fairly large 12 Volt battery for a home security system... So, I decided that since its all just sitting in my room and I can't tie the Solar panel into my home's breaker box (too expensive), I would build something that I could transport around to give me a charge for anything with a USB or Car Charger. I used it outside, inside, camping and even took it to work.
This is how I did it....
Step 1: Gather Tools and Materials
Materials you will need:
1. Briefcase (bought mine from Goodwill for $5.00 and mine was very tough plastic with big metal hinges)
2. Solar panel or a group of cells that will fit nicely on your briefcase
3. 12 Volt solar charge regulator (Amazon.com sells them for around $25.00, you could most likely build one using a capacitor and a diode)
4. 12 Volt battery (I got mine from an unused security system)
5. 1x6 piece of wood long enough to fit in your case
6. Small piece of cloth or some paint to coat your piece of wood
7. Multiple socket car charger (I bought mine at Walmart for $15.00 but now I see they are only $5.00 on Amazon.com)
8. Some extra wire to connect the regulator to your battery (I just trimmed some off of my solar panel)
9. Screws and
10. Bolts with washers and nuts
11. Electrical Tape
12. Zip Tie or Velcro Strap
Tools you will need:
1. Power Drill
3. Screw drivers (phillips and flat head)
4. Wire strippers
5. Saw (Jig and Table)
Step 2: Attach the Solar Panel
1. Place your solar panel on the outside of your case and mark 4 spots so that they hold down the panel from underneath it.
2. Drill your holes for the bolts and wait until you lightly tighten it down to mark your hole for the wire to go through.
3. Remove the solar panel, drill your wire hole and then tighten down your solar panel tight. I was able to put the bolts in and then slide my panel onto them because it acted as if it were on tracks.
4. Pull your wire through and lay it out in the case making sure to give yourself enough room to open and close the case (make sure you don't cut or pinch the wire).
Step 3: Cut and Install the Wood Brace
1. Measure then cut the 1x6 piece of wood so that it fits snug inside the case.
2. Trace out and then cut holes for the battery and the multiple socket car charger (leave space for the voltage regulator).
3. Wrap the wood in cloth.
4. Place the components inside the brace and then adjust to where you would like it.
5. Screw it down from the outside, I used 4 black screws (2 on either side).
Step 4: Wire the Components
1. Strip your multiple socket car charger wires and either solder or tape it to your battery also add the wire for the voltage regulator (leave any fuses if possible).
2. Place your multiple car charger and battery in the wood brace, strap the battery down.
3. Install and screw down your voltage regulator, tighten down your wires from the battery to the "To Battery" markings on the regulator.
4. Finally attach your solar panel to the voltage regulator.
Step 5: Take Your Briefcase Outside!
The entire set up gives you a very nice view of how things are working. When your solar panel is making power, your voltage regulator's LED will light up telling you that it's working. Then, your car charger's LED will light up telling you that its receiving power. Finally, after you plug your phone in, and it beeps, it tells you that it is getting free wonderful power from the sun!
The entire set up with battery, giant briefcase, and large solar panel weights about 10 lbs so it's surprising light for an entire system. I am not sure how long it takes to fully charge the battery but I am sure someone would be able to calculate how much power the battery could give off.
I also brought along a hand generator (from a kids kit) and actually if you spin it fast enough was able to charge my battery as well! Just make sure to screw it into the voltage regulator.
Now make your own, take a trip, go camping, or just enjoy a nice time at a park with your laptop soaking up the sun while charging your electronics!
"If it ain't broke, make it better!" - Chris W.