How to Make a Solar House

In my intro to engineering class, we were assigned to design and wire a model solar house out of cardboard. This house uses 3 loads; a fan, LEDS, and a speaker, and two types of supplies; 3 solar panels and a portable charger battery. I wired these materials together to create a fully functioning model house.

This project requires:

• cardboard
• hot glue
• box cutter
• pencil
• ruler
• protractor
• 16 gauge wire
• wire stripper
• duct tape
• fan
• music speaker
• 12 volt solar panels
• LEDS
• switches
• USB car charger
• mini multimeters
• USB cable switch
• soldering iron + solder
• euro splicing blocks
• resistor

It's important to have an idea of what you want to build before you start building it. I first created a rough sketch of my house. When designing it, I kept in mind the roof angle that will be the most solar efficient. Since I live 38° latitude, that is the angle that I tilted my roof in order for the solar panels to get the most sunlight, which is called the max panel tilt. I also left the front open so that it's easier to build the wiring inside.

Next, I cut the cardboard into the shapes I wanted and used hot glue to connect the pieces together. It's important to use a ruler for this part so that the pieces can fit together better. Make sure everything is well connected and has supports so that it's sturdy.

To create the 38° roof, I used a protractor to measure out the angle and connected the two roof pieces together in the middle.

To make wiring easier, I laid out all of the materials on cardboard. Firstly, I made sure I knew what all the materials are and what they do. Then, I brainstormed how I could attach them in order to make everything work. In the beginning stages of wiring, it important to know that there has to be a load side and a supply side.

In my initial wire design, I have all of my panels connected in parallel to a car charger, which is used to step the power down to 5 volts so the loads don't short out. The battery is a supply itself, but the solar panels are also used to charge the battery so it doesn't die. It goes to a switch that is used to turn on and off the loads. The LED goes through a resistor so it doesn't burn out.

At this point in the project I didn't have the speaker yet which is why it's not shown, but once I had the speaker I attached it in parallel like all of the other loads.

To create more light in the house, I wired 3 LEDS together in parallel. Whenever you wire an LED you have to add a resistor so that the light doesn't burn out. All of the positives should go to the positive side (the long end of the LED), and all of the negatives should go together too. The resistor can be on either the negative or the positive side. Once I had these organized, I soldered them together to create a strong connection.

Next, I added switches to all of my loads. Since the switches don't need to go positive-positive and negative-negative, you can add them to either side of your loads. This is because the purpose of switches is to cut the current, so it doesn't matter which side it is on. Switches are really important because they allow you to have a lot more control over the systems inside your house.

A huge part of this project is troubleshooting. Throughout my wiring, I made a lot of discoveries that led me to my finished product. It's important to test all of your materials first so that you don't end up soldering a dead LED or using a solar panel that doesn't work. At one point I soldered my resistor to the wrong part of the LEDS which made one of them burn out.

In my initial design, I attached some loads in parallel and some in series. After talking with a solar expert, he explained that connecting all of my loads in parallel would work better for my house, so I changed my wiring, and added two euro splicers to organize my wires better and make good connections.

Throughout designing a solar house you may run into some obstacles, but it's important to be open to changing your design, or wiring something differently in order to make it work.

Once I had my wiring done, I began to add the wiring of the supply side to my cardboard house. I attached the solar panels to my roof by standing them on small pieces of cardboard, making them removable. I attached the wires and chargers using electrical tape, trying to keep them as organized as possible.

Make sure when you attached the wires to your house you make them removable in order to be able to change things while you are working.

After I finished with the supply side of my house, I moved to the load side and attached all of that. It's difficult trying to keep those wires organized, but as long as the on and off switches are easily accessed then that's what matters. With my LEDS, music box, and fan, I created holes in the walls and roof of my house to stick them through in order to not have the mess of wires inside my house. Again, I connected the wires with tape to the outside.

Now you're done! All that's left is to turn on all of your appliances to make sure everything works, and put it outside to test the solar power. You can use the mini multimeter to see how many volts and amps your different appliances and supplies produce.