How Solar Panels Work

“How Solar Panels/Cells Work” Solar panels are made of thousands of solar cells and are used to use light and heat energy from the sun. These solar cells/panels can use the energy they have absorbed from the sun’s rays and use it to power most of the machines we use that use fossil fuels to power them. The purpose of the solar panels/cells is that we can get as much energy as we need to power our machines, homes, and tools we use in are everyday life, it is also a way to get free energy we don’t have to compete with other nations for, and we could have on energy source that wouldn’t hurt our own atmosphere and destroy our environment. The only problem with solar panels is that they can’t pick up a lot of the solar energy that shines though earth.

How Solar Panels/Cells are made. Solar panels are nothing more than modules of solar cells or photovoltaic cells. These cells are made of different layers of material that help the cells perform their function. There are six different layers on the Photovoltaic Cell. They are the N-type (negative) silicon, P-type (positive) silicon, the back contact, the front contact grid, the anti-reflective covering, and the glass cover.

The silicon is in its crystalline form which is created when a silicon atom links with other silicon atoms. This is important for the PV Cell. The silicon has to be modified a bit to work as a solar cell because silicon is a poor conductor. The silicon in the solar cells is doped (adding impurities on purpose) with phosphorous atoms so it has impurities in it that change the way the silicon works and cause the silicon to help the PV cell. The phosphorous atoms in the silicon give the silicon a negative charge because the phosphorous atom has one extra electron with is released when the phosphorous atom links with the silicon atoms. The extra electrons take less energy to knock the electrons from their

atoms since they aren’t linked with any neighbors which causes the electrons to freely move around the silicon. This is how the N-type silicon is created. The P-type silicon follows the same process as the N-type silicon, but instead of being doped with phosphorous atoms the silicon is doped with boron atoms which only have one less electron than the silicon atoms. This causes the silicon to have free holes with instead of having a negative charge they have a positive charge. This shows how the P-type silicon is created. The N-type and P-type silicones are merged or placed together. When this occurs an electric field forms in between the two silicones without this electric field the solar cell is useless. The electric field happens because the free electrons in the N-type silicon will try to find the free holes which are in the Ptype silicon. The electrons will jump from the N-type silicon to the P-type silicon which creates a spark of electricity and the electric field. The front and back contacts of the solar cell keep the two silicones together so the electric field will keep on working. The anti-reflective coating allows the sunlight to be absorbed by the solar cell which helps the electric field by causing

the silicon’s electrons to move faster which will create more energy instead of being reflected off which will cause the PV Cell to lose power. The glass on the Solar cell is used to protect the Solar Cell from being destroyed from the elements.

How Solar Panels/Cells create energy. The electrons don’t fill all the free holes when they meet at the middle of the junction of the two silicones. They create a barrier that makes it harder for the electrons to go to the P-side from the N-side. Finally, when equilibrium is reached, the electric field will completely separate the two sides. The electric field becomes a diode which allows the electrons to go from the P-side to the N-side, but not the other way around. Sunlight in the form of photons will hit the solar cell which will free one electron and a free hole as well. If this happens close enough to the electric field The free hole and the electron will jump to their original sides which causes the

electric field to be disrupted and all the free holes and electrons will try to go back to their original sides. If there is an external current path at the time this occurs the electron flow will cause the current, and the PV cells electric field will create the voltage. When those two factors combine it creates power with is the product of the two.