Solar Panels

Solar Module (Panel) can be defined as  number of individual solar cells connected together in an environmentally
protected housing / casing  and produces  a standard output voltage and power.


 Hence Multiple modules/panels can be assembled into an array
 for increased power and/or voltage.
See Image below:

That means, a Solar Cell is The basic unit of a photo-voltaic solar panel.

A 12 volt solar panel typically has 36 individual cells, a 24 volt solar panel uses 72 cells.

  In summary, Solar panels are made up of solar cells that are connected together to form a module.

The cell   is primarily made up of silicon, and when placed under the sun they produce dc voltage. (D.C)


 Solar panels can last up to 20 years and even more. They can be Fixed, Adjustable or the
Tracking  Type.

Roof Mount

Ground Mount

Pole Mount

You can decide to go for a complete panel from manufacturers (already made) or build panels by yourself using solar cells.
 Solar panel is rated In watts e.g. you can have a panel rated 50 w, 100 watts, 200 watts etc.

Basically, There are three types of solar panels and they are:

a.Mono-crystalline Solar Panels

b.Poly-crystalline Solar panels

c.Amorphous Solar panels

a. Monocrystalline Panels: These are the most efficient and most expensive solar panels but i assure you that they are worth every penny you spend on them. these panels are made from monocrystalline cells, and are made from very pure silicon cells. this cells are sliced in from pure silicon rods into wafers that form the individual cells that make up the Solar panel (Module)

b. Poly Crystalline Solar Panels:
These panels are made from polychrystaline cells and are popularly called multicrystalline cells. they are much cheaper than the monocrystalline panels and this is because

The cells are grown in a block of many crystals and not in slices of wafer like the mono crystalline cells, and that is what give them the shattered glass appearance.

c.Amorphous Solar Panels: These are not really crystals, but a thin layer of silicon deposited on a base material such as metal or glass to create the solar panel.
They are are much cheaper, but their energy efficiency is also much less and because of this, more square footage is required to produce the same amount of power as the Monocrystalline or Polycrystalline type of solar panel.


When ever you want to purchase any solar panel, please pay close attention to the information written behind the panel. its very important.

Based On the screenshots above, there are some parameters you need to pay close attention to, they are:

 i   Maximum power rating  (Pmax)
 ii  Voltage at maximum power, (Vmp)
 iii Current at maximum power (Imp)
 iv Nominal operating temperature
 v  Cell technology.

This particular solar panel is meant for a 24 volts system, and because of that the actual voltage produced by the panels need to be high enough to prevent the backward flow of current from damaging you solar panels.

the product of the voltage produced  Vmp  and the current Imp produced at maximum power must be up to at least 85% of the panels rated power output

for instance the above panel has a power out put of 200watts. but if u multiply Vmp x Imp = 36.0 x 4.96

= 175 watts its not up to 200 Watts and the reason for this is stated in my previous post, in that post, i said that due to energy losses that occur, no system is capable of being 100 % efficient and so we assume an efficiency of 85% and then  factor it into whatever calculation we would be making.

 In this case the efficiency of our panel can be calculated as thus:

175Watts/200watts X  100= 87.5 Percent. this is very OK.

if you were using a poly-crystalline or amorphous panel, your efficiency would be considerably lower than the above.

Nominal operating temperature: This  refers to the maximum temperature the panels can withstand without having considerable effect on the power output.

Cell Technology is also very important too. as you can see, this particular panel is made of mono crystalline  and based on the comparison i made above i hope you now agree realize that mono-crystalline panels are the best most efficient solar panels your money can buy.

Points to Take Note of Regarding Solar Panels

1.Your solar panels should be far away from any shady area, if possible, cut any tree that may inter fare with  your panels from receiving direct sunlight, to prevent current from flowing backwards from your battery and destroying your solar panel.

2.Make sure your circuit breaker is switched of before you decide to carry out any routine maintenance or upgrade on your panels.

3.wipe your panels clean  at-least twice a year, to remove accumulated dust particles that may have settled on it.
Dust particles can reduced the efficiency of your solar panels, but if you live in an area that isn't that dusty, you could rely on rain Rain fall to wash your panels for you.

4.As previously stated in point 1, your solar panels should the installed far away from any nearby shade capable of casting it shadow on your panels, in other words your panels need to be installed where they can receive the maximum amount of sunlight  But, another problem you have to deal with is heat build-up because this can also become a problem. and the reason is Because the efficiency of solar panels decreases as temperature increases, putting that point into consideration, your solar panel  mounting system should have allowance between  the individual solar panels for air circulation. that way that way, your panels can easily be cooled despite being under the hot sun which would subsequently reduce the temperature of your panels.

this will also reduce wind resistance around your solar array since a path has now been created for the air to pass through.