Taking a Look at How Solar Panels Operate
The basic principle of solar panels is pretty well known: Sunlight hits the panel and electricity comes out. However, the process in between remains a mystery to many people, who often wonder, “How does it work?” “How do you go from a ray of sun to powering a hot stove top?” To answer these questions, perhaps the best place to start is with the most elemental components of solar panels.
Sunlight falls on the solar panels, even on cloudy days.
- SOLAR PANELS
The PV cells on the panels convert the suns energy into Direct Current (DC) electricity which is sent to the inverter.
The DC current flows into the inverter, which converts it to Alternating Current (AC) electricity ready to use.
The AC current is fed through a meter and then into the home.
- POWERING THE HOME
The system will automatically use the free electricity you've generated and switch back to the grid as needed.
- THE GRID
When the solar energy system produces more electricity than is needed, excess electricity is automatically sent to the utility company. This will cause the electric meter to run backwards.
The excess electricity produced by a solar energy system is sold back to the utility company.
The Basic Construction of a Solar Panel
The true base of any panel, silicon, is not only Earth’s most prevalent semiconductor, but it is also one of the most common elements of any kind on our planet, second only to oxygen. Extracted as sand from the earth, chunks of silicon are crystallized and shaped into rectangular columns. These columns are then cut into extremely thin slices known as wafers. The highly pure silicon wafers are converted into solar cells, which are the main building blocks of any solar system and are strung together to form the panels themselves.
A solar (or photovoltaic) cell has two main silicon layers — a top, phosphorus-diffused layer that carries electrons and is negatively charged, and a thicker, boron-doped bottom layer that contains holes, or absences of electrons, and is positively charged. The electrical imbalance between these two layers is essentially what makes solar power possible. Light radiation causes each layer’s positive and negative charge carriers to be released in the cells and in turn causes electrical current (direct current) to flow.
In more detail, the process is as follows:
- Solar radiation in the form of photons hits and penetrates the solar panel cells.
- These photons activate electrons in both the top and bottom silicon layers of a solar cell.
- Some of these activated electrons slingshot from the bottom to the top of the cell.
- As they move, the electrons flow into metal contacts as electricity and move into a circuit that runs throughout the 60-cell solar panel.
- The electrons flow through this closed circuit and eventually come back to the cell via a solid contact layer at its bottom.