Before I go on to explain the different materials and components you need to build a solar panel, I must take some time to explain an important thought with you: you do not have to be an engineer of any sort to build a professional looking (and working) solar panel system.
You however need to know some basic soldering and this can be learned in a short span of 5 minutes…flat. You’ll also need to start your imagination engine so you’ll know how you’ll be using your solar panel to power your electrical devices.
In case you do not have any DIY skills at all, you can always buy ready-made solar panels complete with mounting brackets and connect the electrical wiring from there. This will be a little more expensive, of course.
Now, let’s look at the materials we need:
1. Solar Cells
3. Jones Plug
4. Silicone Caulk
5. Super glue and screws
Depending on your budget, you can either buy new cells or purchase slightly damaged ones. Yes, you can certainly put together broken solar cells. However if you’re not confident doing this, my best suggestion is to spend a little more money to buy new cells from eBay.
No matter how small your project is, unless you’re very skillful with woodworking, you’ll probably need 3/8” thick plywood. A very good idea that I came across is to use a sturdy photo frame (metallic or wooden one) and work from there. At least you don’t need to put in too much effort for the solar panel frame. You can get plywood easily from your local hardware store.
This is a two-pin plug that terminates the end of the wires that comes out from the solar panel so you can plug this into your electrical system. You can find these at Newark Electronics or sometimes at eBay.
This is a strong, waterproof seal that is used for fixing household items like our bathtubs and kitchen sink. Your local hardware shop sells silicone caulk.
Super glue and screws
Some super glue is useful to hold the pieces together before you screw them down firmly. Again, your local hardware shop probably sells super glue and screws.
It is best to get those wires that come in a twisted pair of red and black so that you can be very sure of the polarity as you solder up the wires.
Choose paint with UV protection so that it can protect against the continual UV radiation beating against the materials.
This component only allows electricity to flow in one direction of your choice. This is needed so that your battery will not be drained into the solar panel during the night or when the sky gets too cloudy.
This provides a protective cover over the solar cells. Plexiglass has various advantages over glass – it doesn’t break easily and is much easier to handle.
One of the most important parts of the solar energy system is the battery. It ensures that electricity is available to your electrical application when there isn’t enough power output from the solar panel (probably due to a cloudy day or during the night).
These are the components you’ll need to put together a complete solar power generator that can supply a small electrical application.
Connecting the Solar Cells
Each solar cell produces 0.5V. To get 18V, we can join 36 solar cells in series. Assuming the solar cells are of the same quality, a larger solar cell will produce more current and thus more power.
You should always ensure that the power generated by the solar panel is sufficient to charge your battery. Otherwise you may have to join more cells in parallel.
If you want to connect the solar panel directly to your appliance, you can simply make-do with 12V output from the solar panel. This is however not advisable for most applications…unless you need your appliance to work only when the sun is out.
Constructing the Solar Panel Frame
Next, we have to create a shallow box (as solar panel frame) for the solar cells to sit in. The borders of the box should be about ¾” wide by ¾” high. If this too high, it will cast a shadow on the cells as the sun comes in from the side. If it is too low, it doesn’t allow sufficient clearance for the solar cells.
Before you screw the pieces of plywood together, you can first hold them together by super glue so they’ll stay in place as you turn in the screws.
Putting the Array of Solar Cells Into The Solar Panel Frame
To get the solar cells into the solar panel frame, glue the array of solar cells onto a thin, rigid backing before placing it into the “box”. An example of this thin, rigid backing is a Masonite board.
We should give the rigid backing a few coats of paint before pasting the cells on. We must also apply a few coats of paint to the panel frame and dry it thoroughly before putting in the array of solar cells.
Connecting the Diode
Connect the diode at the power output of the solar panel. You should locate this inside the solar panel and hold it down using some silicone caulk so it won’t move about.
Placing the Plexiglass Cover
Before covering the solar panel with the plexiglass cover, test again to see that you’ve got the correct voltage and power output. Then carefully drill the holes (for the screws) at the border of the plexiglass.
Take care to apply moderate, consistent pressure while drilling so that the plexiglass won’t crack. Also remember to countersink the hole so that you can flush the screws with the surface, if necessary.
Attaching the Jones Plug and Battery
At the end of the wire that dangles out of the solar panel, attach the (male) Jones plug by soldering them on. Also solder the female Jones plug to the battery terminals according to their polarity.
Using a connector like a Jones plug makes it convenient for you to disconnect the solar panel from the battery if you need to.
And after hooking up the parts in the above manner, you’ve made for yourself a complete solar power generator that can power up your electrical gadgets — anything that runs on 12V.
The Solar Panel Frame
The best material to use for the solar panel frame is aluminum. This is a material that will not rust easily and it’s able to carry away additional heat that may be trapped inside the solar panel. This is particularly important since heat can diminish the efficiency of the photovoltaic cells.
The diodes you should be using are the Schottky types. These diodes have a much lower forward voltage drop so less power is wasted. And when the temperature gets higher the forward voltage drops further.
Solar Panel Cover
If budget allows and there is no hail at your area, the best cover that your solar panel can have is made of non-reflective glass. Solar panels covered with non-reflective glass can enjoy significantly higher efficiency because greater proportions of sunlight reach the solar cells.
If you intend to power outdoor equipment like sprinklers and gate openers, your battery will need to be sheltered from the rain and dew. Unfortunately it may be impractical to house these indoors as we’ll then need very long wires that may also be a safety hazard if it’s left lying around.
You can put the battery (or batteries) into a waterproofed electronics housing and seal up the opening (for the wires). In this way rain or dew will not cause short circuit to the battery.
By implementing all of the above tips to your solar panel project, you can surely make for yourself a world-class DIY solar panel project.