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Building a homemade solar panel from scratch is a great way to take advantage of the free power you can generate from sunlight without spending a lot of money on expensive commercial solar panels.
Locating the parts you’ll need to assemble the panel is easy and many of them can actually be found locally at your neighborhood hardware store.
You actually may even have many of them around the house and can lower the cost of your homemade solar panels even more.
There are also a number of good assembly manuals available on the web that can help you understand the steps involved in building your own solar panel and most of them also include a list of dealers that can supply any of the parts you may still need to finish your project.
The basic assembly of a solar panel involves finding a set of solar cells (for sale) that can be used in your panel.
These solar cells are available from a variety of locations and vary in price depending on their quality and composition.
Two Types of Solar Cells
Basically there are two types of solar cells and which one you decide to build and use depends on what you are using the finished solar panel for, and your budget.
The most efficient type of solar cell is called a monocrystalline cell and is made from a single large silicon crystal. Because the crystal is grown as a single unit, it is purer than other cells and will deliver a larger amount of power when exposed to sunlight.
These monocrystalline solar cells are more expensive than other versions, but will deliver far more power when used in your project. These are the perfect solar cells to use if you intend on using the completed homemade solar panel for high demand applications like a home solar power system.
The other type of solar cell is called a polycrystalline cell and is comprised of several smaller cells that have been joined together to form a single cell.
This is a less expensive type of cell than the monocrystalline, but will generate less power as well.
The polycrystalline cell is the right type of cell to use if you are on a tighter budget, or the homemade solar panel you are building is being used for a less critical application like garden lighting or charging a battery.
Start building your Homemade Solar Panel
Once you have located the solar cells you are going to use to build your panel, you need to decide how to connect them together to provide the correct voltage and current required for your project. Most of these cells will come with a connection diagram to help you assemble them in the right fashion for a given specification.
These diagrams – you can also buy a more detailed manual -should give you clear instructions on how to connect the various solar cells together for a given voltage and current and make it easy to wire them.
In general if you wire them in series you will increase the voltage the solar cells generate as a group. If you connect them in parallel you will increase the current they generate.
Before you start your wiring of the solar cells, you need to mount them to a strong backing board for support. The solar cells are made of a rigid silicon and will be very fragile on their own.
So in order to resist damage from the elements, they need to be attached to a solid backing board, which also makes the wiring of the panels easier.
Plywood is a good choice for this as it’s both lightweight and weatherproof.
A quick way to find the best size for this backing board is to gently lay out your solar cells on the floor in the layout you will be wiring them together and then measure the width and height of the assembly.
Be sure to cut your backing board a little larger on each end to give you room to mount it into a cabinet. Once you have the backing board cut to size you can apply a coat or two of paint to help it resist the elements when it’s finally mounted on your roof.
When this is done, you can simply attach the solar cells to the backing board as they were laid out before and adhere them with a commercial glue to the wood. Give them plenty of time to settle before moving on to the task of wiring so they won’t work loose later.
Soldering and Mounting the Solar Cells
The wiring of the solar cells together is an easy process that will require a bit of skill with a soldering iron – especially if you bought wired cells already as suggested.
You’ll need to buy a soldering iron and some solder to finish this step, but these are inexpensive items that can be bought from a local hardware store and are also easy to use.
Each of the solar cells will be connected together with a small length of wring that is typically soldered to the tabs provided on each cell.
As you make these connections you can secure the loose wire to the backing board with a bit of caking to eliminate any movement that could lead to intermittent connections over time.
When you are finally finished with the wiring you should end up with a single set of wires from the last solar cell that are used to supply the power from the homemade solar panel to whatever it is you’re using it to power.
Our Solar Panel can be used for charging a battery
But remember that a solar panel gives you Direct Current (DC). For powering your normal home appliances you would need AC. For that we need a so called “inverter”.
Since this step is a bit more complicated, for the sake of this article we stick to the DC current, which is most effective for charging batteries.
At this point you should take the partially completed solar panel out in the sunlight to measure the power it’s providing to make sure you wired everything correctly.
If this checks out you can move on to the final stages of assembly. Once you know you have a working set of solar cells, the last step you need to complete is building a weatherproof enclosure that will house the backing board with the solar cells attached.
This can be built from simple plywood and a piece of Plexiglas used for the top surface that allows the sunlight to enter the enclosure so the solar cells can do their job of converting that sunlight to power that you can use for your project. Be sure that when this enclosure is finished that you have made it secure against the elements to prevent any damage to the solar cells over time.
All that’s left is to mount your homemade solar panel in the sunlight and enjoy the free power it provides.