The sun shines on our planet every day. This powerful light and warmth is what makes life on Earth possible, and clever science allows us to capture this energy to make electricity. Solar power is the process of using the light from the sun to power our homes, schools, and even cars without burning fuel or causing pollution. It is a clean, renewable way to get the energy we need to make things work.
The Sun’s Super Power
The Sun constantly radiates energy out into space. This energy travels to Earth in two main forms: light and heat. Solar power technology uses the light energy from the sun, which is made up of tiny packets called photons. Photons travel incredibly fast, covering the 93 million miles from the Sun to Earth in about eight minutes.
While the heat from the sun is used in other solar technologies, photovoltaic power specifically relies on capturing these light particles. The constant arrival of photons provides a reliable, ongoing supply of raw energy that will not run out.
Catching the Sunshine with Panels
To catch light particles, we use solar panels, which are specialized pieces of equipment designed to turn light into power. Each solar panel is made up of many smaller units called solar cells, also known as photovoltaic cells. These cells are mostly made from silicon, a material derived from sand and rocks.
The solar cells are protected by a glass sheet on top and held together by a sturdy aluminum frame. The frame keeps the structure safe and secure when mounted on a roof or in a large field. The silicon inside the cells is specially prepared to react when light hits it.
The light energy is absorbed by the silicon, and this is where the conversion process begins. This structural design ensures that the maximum amount of sunlight is collected and prepared for the next step.
Turning Light into Usable Electricity
The process of turning light into electricity is called the photovoltaic effect, and it relies on the behavior of electrons within the silicon cells. Silicon is treated with other elements, like phosphorus and boron, to create two different layers: one with extra electrons (a negative or n-type layer) and one with spaces for electrons (a positive or p-type layer). This structure creates an electric field at the junction between the layers.
When a photon from the sunlight strikes the silicon cell, it transfers its energy to an electron within the material. This energy boost is enough to “knock loose” the electron from its atom, making it free to move. Because of the electric field that exists between the two layers, the newly freed electrons are forced to move in a specific direction. This directed movement is what creates an electric current.
The current is the flow of these excited electrons, moving from the negative layer to the positive layer through an external circuit. All the individual solar cells are connected together to combine their small currents into one larger flow of electricity.
Sending the Power Where It Needs to Go
The electricity that comes directly out of the solar panels is called Direct Current (DC). DC electricity flows in only one direction, which is fine for charging a battery but not what most household appliances use. The electricity that powers the lights, televisions, and refrigerators in a home is called Alternating Current (AC).
This is where a device called an inverter comes into the system, acting as a translator for the electricity. The inverter takes the DC power produced by the panels and quickly converts it into usable AC power. Once the electricity has been converted, it flows through the home’s main electrical panel and out to the various outlets and appliances.
If the panels make more AC electricity than the house needs at that moment, the excess power can be sent out to the larger electrical network, often called the grid. Alternatively, the extra power can be stored in large battery systems for use at night or on cloudy days.