solar panel array Background

 

 

What is a Solar Panel and How Does it Work?

Solar panel internalsSolar panels, also known as Photo Voltaic Cells, are made from composite materials. The power producing component inside of a solar panel (solar cell), is made of mainly silicon; the stuff under your feet at the beach! When a solar cell is exposed to sunlight, photons (also known as light energy) move electrons (also known as electrical energy), is created, moving only whenever a load is connected. In layman terms, light energy is converted to electrical energy and that energy works, dissipating power, whenever a load is connected to the output.


Solar panels contain several individual solar cells which is connected in series to produce either 12 or 24 volts DC. A 12 volt solar panel contains 36 solar cells, while a 24 volt one contains 72. Each cell is capable of producing approximately .5 volts. The power output (watts) of the cell depends on the surface area mass. So the bigger the solar cell, the higher the power rating.


If a solar cell was broken into several pieces, each piece would still produce around .5 volts, although each piece will have varying power ratings, as each piece would have varying masses. So you could technically make a 12 volt solar panel from a single cell, if that cell was cut into 36 equal size pieces and then connected in series.


A 12 volt solar panel technically should generate more than 18 volts. 18 volts is the MINIMUM charging voltage for 12 volt SLA (Sealed Lead Acid) batteries. When a 12 volt rated solar panel is exposed to full sunlight though, it can produce more than 20 volts, which is why a solar charge controller is usually a necessity for any off grid system.


Building Solar Panels


Applying flux for soldering...

Applying flux to solar cell

Solar panels are usually assembled with the most stringent of procedures. All passive component inside the panel must be free from all external conditions, such as moisture and impurities which could create internal short circuits or arcing. The solar cells inside the panel can last for more than 30 years when protected against external eliments! Understandably, the cells will need protection from the elements for at least more than 25 years. That’s why the most stringent of processes must be carried out during the manufacture of solar panels...

 


Can I Build My Own Solar Panels? Course you can!


Soldering on the solar tabs...

Tabbing a solar cell

But in most cases though, the solar panels will most likely not be as good or as long lasting as a solar panel that’s been industrially manufactured. Technically though, you could build a solar panel from home, but without the right type of protection, your solar panel may not see past 5 years! Solar cells are super cheap, so if you already had access to materials such as glass, encapsulant, aluminium C-Channel and all the materials needed for assembling it, then you can make a solar panel for as low as just a few dollar over the price of solar cells! Some of the best known home made solar panels CAN, last up to more than 10 years! We have one we built more than 15 years ago and it is now producing 88% of its full capacity! So yeh, it can be done; although, with some hard work!

 

So What Makes a Solar Panel Last for a Long Time?


EVA Encapsulant...

EVA encapsulant

Encapsulation is the process of permanently sealing the solar cells inside the panel - The better this process, the longer the panel life, or, the longer the life of the cells inside the panel plus the wiring integrity as well.

If you can picture the windshield of an automobile; that, uses EVA between 2 sheets of glass - that's why your car windscreen is so strong! That's exactly the same way a solar panel is sealed and it is permenant!

 

Before a solar panel can be encapsulated, all impurities, especially where there are residues at the soldered connections, must be cleaned thoroughly with a solvent, such as isopropyl alcohol. If the panel were to last for a long time, then the electrical integrity of the panel must not be compromised by external elements or impurities on the soldered joins of the cells...


Testing a solar cell String...

solar cell being tested

Building your own solar panels is a great way to learn about solar energy; and in regards to small systems, it can be a great way to save money. Small solar panels can be used for a number of power requiring tasks, but when you’re talking going big though, building the solar panels yourself is not a very good idea, or at least, not in my opinion.
Building solar panels involves many details and sweat! Soldering the connections for the cells involves a fair bit of skill; there are 36 of those for a 12 volt panel and 72 for a 24 volt one. Plus, solar cells are very easy to break as they are very fragile, kinda like egg shells!


As for myself, building a single solar panel was quite a tedious task; and I’m an experienced techy! One time was enough though. Will I build my own solar panels in the future? I don’t think so! Besides, solar panels are much cheaper now!


My past project...

If you still choose to build your own solar panels, I recommend that you start small. If you find you enjoy it, then you may wish to go larger! Building your own solar panels can be fun and is certainly educational, but with cheap solar panels now available, it’s probably a better idea to just buy one. On the other hand, being equipped with knowledge can really get you out of trouble, should a disaster happen. If you happen to go ahead and build your own solar panels, then I recommend that you read this page first...


 

 

 

Super Cheap Solar Panel?


I call this, “the disposable solar power”. Technically, you could just wire solar cells together and then simply give them sun. But you would probably want to throw them out after a few months of usage though!

 


Untabbed solar cell... 60 cents each!

untabbed solar cell

Solar cells are very cheap, so setting up a 1000 watt array is no problem. The only work required for that array would be just tabbing the cells together. This could take just a few hours as opposed to a few days building the whole panel! What you end up with is a bunch of solar cells on a table, producing power…  But it’s only short lived before the elements totally devour it!


At the end of the day, nobody wants to worry about any energy issues for at least a few years; the longer the better! Solar panels that are manufactured are reliable, offering many years of power production; take note of this before you decide what to do; if you want reliability for years to come.

 

Final notes:

 

At the end of the day, how much you spend on a solar power system will in most cases weigh up between reliability versus costs - The higher the risks; the lower the costs!

 

Building your own solar panels is risky business as far as reliability is concerned, although the higher the technical understanding; the lower the risks!

 

If you intend on building your own solar panels for your energy system, but lack the know how to make it happen, then we recommend you get expert help. There are many specialised guides out there, that can help non-technical people build their own solar panels; that's covered here...

 

 

 

 

 

 

 

 

 

"Make It Solar Powered! "

 

 

 

 

 


Free eBook!

Learn about solar cells and how to make your own solar panels...

Free eBook on how to build a solar panel

Enter your NAME & EMAIL in the form below and we'll deliver your copy directly to your inbox...


Solar Panels Info

 


Downloads