How to Build a Solar-Powered Cardboard House W/ Loads

This is a solar-powered cardboard house. It has three LED lights, a fan, and a speaker inside. The LEDs are wired in parallel and so are the fan and speaker. All the loads are connected to the three solar panels. This Instructable teaches you how to wire a cardboard house and provides tips on how to build it in the first place.

Supplies

Materials:

(1) Small Fan

(6) Euro Splicing blocks

(1) Music Speaker

(1) USB Car Charger

(2) USB Cable switches - modify one to expose wiring on one side as seen in photo

(3) LEDs

(3) Switches (if wanted)

(1) Battery

Lots of Cardboard

Tools:

Hot Glue Gun

Soldering Iron + Helping Hands

Heat Shrink Gun

Scissors

Razor Blade

Painters Tape

Step 1: Begin Constructing Your Cardboard House

First things first, once you've acquired the materials detailed previously, you need to start making your house. This house is beach house inspired, but you can go in any direction with your design. I used hot glue to keep everything sturdy. A few other tips for house-building are..

Make sure you have a solid foundation. You don't want to be limited later in your design by a weak building.
Don't overuse hot glue + clean up the "strings" of glue left behind. This is more of a neatness thing than anything, but big globs of hot glue can get in the way later.
Secure your roof! A strong roof is a necessity because you'll be mounting heavy solar panels on it later. Also, don't make it overly pitched, it'll be harder to mount the panels.
Make it look good and add detailing! If you have spare time it never hurts to make your project more unique.

MOST IMPORTANTLY: Leave a side of the house open. (i.e. only three walls) The inside needs to be accessible for your future wiring. Think "Barbie Dreamhouse."

Step 2: Once You've Completed the House, Plan Where You'd Like Your Loads

Now that you've finished your house, you need to start planning out what components you want, and where they should go.

First, decide where you want your solar panels. You'll need to position them at the best solar azimuth and solar altitude.

The solar azimuth in the position of the sun in the sky with relation to a compass (i.e. North, South). The sun goes east to west, and depending on where you are in the world can be in the northern part of the sky or the southern part. The best positioning for a stationary solar panel is toward the side the sun's path is on.
The solar altitude is the position of the sun in the sky measured by an angle. Your solar altitude corresponds to the latitude of your location.

Then, choose the places to put your LEDs, fan, and speaker. Remember, these don't have to be your final decision, but they will help you get started.

Step 3: Wire Your Circuit Outside the House

Wire your circuit outside of your house to ensure that it works. Connect your solar panels to your battery input in a parallel circuit. Then, connect your LEDs, speaker, and fan to the battery, also in parallel.

A parallel circuit is pretty simple: Connect all of your negatively charged wires to the batteries' negative output wire, and connect all your positively charged wires to the batteries' positive wire. I recommend using a power splicing block, which isn't shown in the supplies photo, to organize everything and keep it contained better.

Remember to label everything clearly, and ideally do it somewhere you can leave it.

MAKE SURE to solder a resistor to your LEDs before you start using them. I made that mistake in this project and had to rewire things when I thought I was done. Even if your lights seem like they're working fine, they could burn out after extended use.

Step 4: Begin Wiring Your House

Now that you have everything laid out, it's time to begin installation. First install your battery and switches. This will allow you to test everything as you go. I suggest only using tape to install things right now, you'll probably want to move things around later on.

Step 5: Continue Wiring

Next, you'll want to place your loads in the preplanned spots and connect everything the way you had it on your circuit. Use alligator clips and don't solder anything yet. Again, you never know if you'll want to change things. Don't worry if things are messy, you can clean things and cover things up later.

Step 6: Ensure Your Loads Are Functioning Properly

Start testing! Flip some switches and check how things are looking. If your lights are coming on, your fan is running, and your speaker is blaring, you're looking good! If things aren't coming on, don't panic. Some easy ways to troubleshoot are:

Check all your connections. If the two prongs of an LED are touching each other, it won't work. Also, if you mixed up the positive and negative and the LED, it won't function either.
Make sure the switches are on. It might seem silly, but sometimes you just forget to switch things on!
See if your battery is all charged up. If you've been testing things for a while, your battery could be dead.

Step 7: Make Things Permanent (if You Want)

Now that you have everything tested and in place, consider soldering it all together. By soldering and customizing your wire length, you can keep everything neater and ensure greater strength and reliability.

For my personal project, I'd planned on just using the alligator clips and leaving it all as it was. However, due to later issues and constraints, I ended up soldering the LEDs.

Step 8: Start Cleaning Up

Clean up everything and try to keep wires organized and against the wall. If you're pretty happy with where things are, you can use hot glue. If not, use tape. You can also cover things up with cardboard boxes and such if that works better.

Of course, if the messiness isn't an issue to you, you don't have to worry about it.

Step 9: Cover Things Up

Finally, once you've cleaned up the inside you can start covering up your open wall. Secure your last wall with painters tape so in case you need to access the inside later, you can do so.