How Does A Solar Module Harness Solar Energy?

Understanding Monocrystalline and Polycrystalline Solar Cells

In the year 1839, French physicist Edmond Becquerel discovered the photovoltaic (PV) effect. It was during his experiments with wet cells when he noticed that the silver electrode could produce more electricity upon exposure to sunlight. 50 years later, William Grylls Adams and Richard Evans Day conduct thermal experiments with Selenium, and stated that  “it was clear that a current could be started in selenium by the action of the light alone.” (Sic)

However, it was the year 1905, when Sir Albert Einstein published a paper on the photoelectric effect of light which helped generate more attention for solar power on a broader scale. The paper states that the sunlight is made up of small packets of energy called quanta or photons.

Later in the year 1945, Bell Labs created the first silicon solar cells with the help of three scientists: Daryl Chapin, Calvin Fuller, and Gerald Pearson.

The making of a solar cell

The modern-day Solar panels that you know are made up of strings of solar cells connected in series.

Although there are different kinds of solar cells available, there we will focus on the manufacturing of monocrystalline and polycrystalline solar cells.

Monocrystalline Solar cells

Monocrystalline solar cells are made from a single rod (cylindrical ingot) of monocrystalline silicon.

In general, these solar cells come in the form of thin wafers of silicon. The wafers are cut from a rod of silicon which is made using industrial processes like the Czochralski Method.

Polycrystalline Solar Cells

Polycrystalline Solar Cells are made from a molten mix of silicon. This mix contains many different silicon Crystals that bind together to form a sheet of silicon as the mix cools down.

This means that a single solar cell made from this molten mix will contain many different crystals of silicon. Hence, they are known as polycrystalline solar cells.

Major differences between Monocrystalline Solar cellsand Polycrystalline Solar Cells

• The first difference you'll notice between the two solar cells their color. Monocrystalline Solar cellsappear black whereas Polycrystalline Solar Cellsappear blue in color.
• Monocrystalline Solar cellsare more efficient in comparison with Polycrystalline Solar Cellsrated at the same voltage output.
• Polycrystalline Solar Cellsare more cost-effective than Monocrystalline Solar cells.

The working of a solar cell?

A solar cell works on the principle of the photovoltaic effect. Direct sunlight hits the surface of a solar cell resulting in the generation of DC voltage.

Solar cells are semiconductors of electricity. This means that upon receiving a stimulus (sunlight) of energy, the electrons in the cells start moving rapidly.

A semiconductor material is made up of three layers: p-type, n-type, and p-n junction; the electrons (after receiving ample energy from the sunlight.) flow through the n-type, creating a hole, which moves to the p-type. The p-n junction serves as a barrier for the electrons and holes. Both electrons and holes move at the same time but in the opposite direction. This leads to the generation on DC voltage.

What is the typical size of a solar panel?

A typical 12-volt solar panel (25 inches by 54 inches) contains 36 cells wired in a series to generate 17 volts of peak output. Each cell in this solar panel produces ½ (.5)  of a volt.

Let's follow the sun

To generate steady energy outputs from a solar power module, one has to keep in mind that the amount of light falling on the solar panel has a direct impact on the amount of DC voltage generated.

Hence when installing a solar power module, look for the areas of your property with direct exposure to sunlight. Also, using devices that increase the efficiency of a solar panel (charge controllers, and optimizers) can be a good idea that will help you make the most of your solar power module.

It will be beneficial for you to consult with a solar power installer before deciding on a solar power module. Having the knowledge of efficiency rates of various solar modules and solar module accessories will come in handy!