Building a solar panel happens to be an extremely technical process, which explains the reason why there were almost no major advances in the field of solar energy until the final quarter of the previous century, when increased developments in the design of photovoltaic cells and semiconductors helped in the formation of more efficient and cost-effective solar cells.
In recent times, it has been made possible for almost any handyman possessing the proper knowledge and tools to build a working solar panel. Such a panel, when built from scratch, happens to be a whole lot cheaper compared to a commercially manufactured solar panel and if well-assembled, it tends to last almost as long.
In order to construct a solar panel from scratch, it is necessary to first be aware of the important materials and components required to piece it together. A basic knowledge of the mechanism of solar energy is preferable — attempting to build such a panel without any prior technical expertise or information poses the danger of failure or, even worse, electrocution. Ignorance can result in a heavy price.
Since the formation of a solar panel is an elaborate process, a number of different materials are involved, most of which are easily available:
- Tile spacers
- Staple gun
- Deck and siding paint
- Tabbing wire
- Bus wire
- Gauge wires
- Deep cycle battery
- Charge controller
- Blocking diode
All these materials and components will be used at some point in the procedure so not much wastage is likely to occur.
The primary step in setting up the intended panel is to form a template for the cells, which is possible using a spare bit of ordinary plywood, a normal cardboard piece about the same size as a solar cell and a staple gun, along with several tile spacers to help hold the solar cells in an even position.
Everything needs to be kept perfectly aligned with the help of a ruler. The plywood piece can be cut easily with a jigsaw. However, a normal hand saw will do just fine.
Once the template is finished, the frame needs to be attached together using another plywood piece measuring 1x2x8 that has been cut in order to fit the outer plywood frame comfortably. It is necessary to ensure that the outer frame is not too large in height so as to prevent it from losing any amount of sunlight. The next step is to place the plywood pieces on top of the plywood which has been subjected to pressure, measuring 2×4, and screw those down firmly, followed by the sanding of the whole frame. After the whole structure has been properly sanded and any additional dust particles left over have been cleaned up, it is time to apply the deck and siding paint directly onto the constructed frame. It is better to apply two coats to make it resistant to water and protect it against UV rays. The piece of pegboard, measuring 2×4, also needs to be given two coasts of the paint.
While the first coat continues to dry, work should be started on putting together the solar cells. When assembling the solar cells correctly, it should be kept in mind that the bottom of the cell represents the positive side while the top part of the solar cell is negative. The solar cells need to be connected together in series, with 36 solar cells in total, which will produce 63 watts, using tabbing wire along with a soldering iron. Three different strings of solar cells will be required for the panel, which need to be connected using bus wire. The bus wire needs to go at the end of the strings to compose one long strip of string, which remains somewhat curled up.
By this time, both the plywood and the pegboard have two coats of paint. It is time to screw the pegboard down within the structure of the plywood frame. Placing the solar cells within the frame first will provide a clear idea on where exactly the screws need to be placed. Once the marks have been made, the solar cells need to be taken back out and the pegboard needs to be screwed down. Next, two distinct holes need to be drilled at the end of the frame for the positive and negative connections to have an opening to run out.
Handling the Solar Cells
The solar cell strings need to be glued down with silicon to the pegboard. At this point, since there are two completed strings, it is better to solder the bus wire on one end in order to bond the two solar cell strings together. It is better to check the current/voltage immediately after soldering any string together or forming new connections, instead of waiting till all the solar strings/cells are connected together.
As soon as all 3 solar cells/strings are hooked in series, it is time to ready the 22 red and black gauge wires for soldering. In order to make the procedure of soldering the gauge wires down to the bus wires much easier, a few connectors need to be connected to the ends of the leads emerging from the gauge wires.
Running the wires inside two wire mold strips makes the inside of the panel look much nicer. The panel is now ready to be taken outside in direct sunlight to check the current/voltage of the entire panel to make sure that there are 18 volts in a circuit which is open and 3.5 amps in a short circuit.
Dealing with Electricity
The electrical side of the solar panel can be demonstrated using an inverter, a charge controller and a deep cycle battery. Hooking these components up is a rather simple process. The connections of the panel first need to be hooked up to the solar part of the charge controller. On the other hand, the deep cycle battery is hooked up to the side of the battery connection present on the charge controller. The inverter is finally hooked up to the battery and the whole setup is ready to go.
To secure the plexiglass piece, measuring 2×4, even pressure needs to be applied around every edge. To make this possible, a separate set of the same outer plywood frame pieces present at the bottom of the plexiglass need to be used to mount on top of it to produce the even amount of pressure needed. The plexiglass needs to be drilled in slowly to avoid producing any cracks. Screws present should be made for pressure-treated lumber.
The back plywood pieces that will be used to support the entire panel should be properly connected. After this step, a junction box is attached to the back of the solar device since the majority of solar gadgets comprise of a junction box. The junction box should have a block diode present to prevent any current from flowing back when the solar panel is connected to the battery. Most of the charge controllers do not allow current backflow, but in case this does not happen, a blocking diode needs to be installed into the back of your device. The blocking diode should ideally be installed on the exterior of the panel so that it could be easily replaced in case anything happens to it.
Lastly, the silicon needs to go all around the sides of the solar panel together with the junction box installed on the back. A final current/voltage check should be carried out prior to mounting the panel.