Why do solar panels produce electricity?

In Australia, for example, people use 20,000 times more solar than energy from oil, gas and coal. As long as the sun is alive, we can still use this source of energy, which is about 5 billion years from now.

To obtain solar energy, people use solar panels (photovoltaic panels). Each plate consists of many photovoltaic cells, which convert solar energy into light into electricity.

Photovoltaic cells generate electricity directly from sunlight. This is the safest energy technology ever used for space satellites and remote areas on Earth, where repair conditions are difficult when a failure occurs.

How do photovoltaic cells work?

Photovoltaic cells are made up of silicon atoms . Silicon atoms are tiny and it takes billions of atoms to make a photoelectric cell.

Each photocell contains a round silicon foil , about 30 cm in diameter, and very thin, only 1/3 of the thickness of a hair. Very high temperatures, up to 1,000 ℃ are used to modify this silicon foil. Then, a metal plate is placed under the silicon foil and above the silicon is a metal mesh. This metal mesh face will face the sun.

60 photovoltaic cells are put together under a glass plate to form a photovoltaic panel.

A home solar power system will use 10 to 50 photovoltaic panels placed on the roof. And power plants will have millions.

Each silicon atom contains an extremely small number of subatomic particles (electrons). Each electron carrying a charger is also very small.

Sunlight on photovoltaic panels releases an electron of a silicon atom.

These free electrons can move but because the photovoltaic cell is specially made, the electrons can only move in one direction in terms of contact with the sun, but not back.

So every time the sun shines on a photovoltaic cell, countless electrons run upwards to form an electrical current that we use for indoor appliances such as lights, TVs and other electrical appliances. .

Each silicon atom has a nucleus in the middle made up of 14 tiny protons and 14 extremely small neutrons.14 electrons run around the nucleus.In fact, a silicon atom does not look exactly like this, but this is a simulation for you to visualize.

If the sky is clear, the more sunlight there is, the more electrons are released and the stronger the current is, the more the sky is dark, the less electrons are released and the current weakens, sometimes only ¼ even less. with a big sunny day.

At night, photovoltaic panels do not produce electricity and we need batteries or other power sources to use.

How are photovoltaic cells being used?

Using photovoltaic cells is the cheapest way to produce electricity , cheaper than new types of coal or nuclear power. Therefore, solar power is being developed all over the world at a rate of 5 times higher than coal power and 20 times higher than that of atomic electricity.

Along with wind energy, solar energy helps us to reduce emissions of greenhouse gases into the atmosphere (gases that cause climate change, adversely affecting the Earth). The cost of using wind and solar energy is very cheap and increasingly cheaper and the more we use these types of energy, the sooner we can stop using other sources of energy from coal, oil, gas, Thanks to that without hurting the Earth.

Moreover, silicon is the second most common material in the world, after only oxygen. In fact, the main component of sand and stone is silicon and oxygen. So we are never afraid of running out of silicon to make photovoltaic cells.

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