When you make any sort of major investment you are going to want to know how it works. The same goes for solar-powered systems when investing in solar panels, most homeowners are going to want to know how solar panels work.

When it comes to how solar-powered systems there are three key parts that everyone interested in solar power should learn how they work: solar panels, solar power inverters, and solar energy batteries.

In the first part of this three-part series of how solar-powered systems work we are going to answer the question of how do solar panels work?

How Solar Panels Work

In 1839, Edmond Becquerel was the first person to discover the effect of photovoltaic cells. He noticed that certain materials would give off sparks of solar electricity when they are struck with sunlight. Researchers soon discovered this as well and coined the term, the photovoltaic effect. The first photovoltaic cells were made of selenium, and were created in the late 1800s. In the 1950s, scientists at Bell Labs began to revisit the technology, and using silicon, they began to produce photovoltaic cells that we're able to convert 4% of the solar energy coming from the sun directly into solar electricity.

How the Photovoltaic Effect Works:

- The silicon photovoltaic cells absorb solar energy radiation.

- When the sun’s rays interact with the silicon cell, electrons start to move, creating a flow of electric current.

- Wires capture and feed this direct current solar electricity to a solar power inverter to be converted into usable alternating current solar electricity.

A Deep Dive into How Solar Panels Work

When it comes to learning how solar panels work, it is very important to know how photovoltaic cells work. The most important components of photovoltaic cells are two layers of semiconductor material that are commonly composed of silicon crystals. The crystallized silicon, on its own, isn’t a very good conductor of solar electricity, however when impurities are intentionally added, the process that is called doping, it sets the stage for creating the electric current.

The bottom layer of the photovoltaic cells us typically doped with boron, which then bonds with the silicon to facilitate a positive charge (P), while the top layer is then doped with phosphorus, which then bonds with the silicon to facilitate a negative charge (N).

When the sunlight enters the cell, the solar energy that is coming from the sunlight knocks electrons loose in both layers. Because of the opposite charges of the layers, the electrons want to flow from the n-type layer to the p-type layer. But the electric field at the P-N junction prevents this from happening.

The external circuit provides the necessary path for electrons the n-type layer to travel to the p-type layer. The electrons flowing through this circuit, typically think wires that are running along the top of the n-type layer, provide the owner of the solar panels with a supply of solar electricity.

Most solar-powered systems are based on individual square photovoltaic cells a few inches on aside. Alone, each cell generates a very little amount of solar power (a few watts), therefore they are grouped as solar panels. The solar panels are either going to be used individually or grouped into a larger array.

Three Basic Types of Photovoltaic Cells:

- Single-Crystal Cells are made in long cylinders and then sliced into thin wafers. This process is energy-intensive and uses more materials, it produces the highest-efficiency of solar energy for photovoltaic cells, meaning that they can convert the most incoming sunlight into solar electricity. The solar panels that are made from single-crystal photovoltaic cells have an efficiency of solar energy of up to 23 percent in some laboratory tests. Single-crystal accounts for a little over one-third of the global market for photovoltaic cells.

- Polycrystalline photovoltaic cells are made from molten silicon that is cast into ingots that are then sliced into squares. While production costs are lower, the efficiency of solar energy in these photovoltaic cells is lower as well, with the top module efficiency of solar energy being close to 20 percent. Polycrystalline photovoltaic cells make up around half of the global photovoltaic cells market.

- Thin Film photovoltaic cells involve spraying or depositing materials, amorphous silicon, cadmium telluride, or others, onto glass or metal surfaces in thin films, making the whole module at one time instead of assembling individual photovoltaic cells. This approach results in lower efficiency of solar energy, but it can be a lower cost as well. Thin-film cells are around ten percent of the global market for photovoltaic cells.

Additional Parts of Solar Panels

Aside from the photovoltaic cells being a key part of the solar panels, the typical solar panels include a glass casing that is going to offer durability and protection for the photovoltaic cells. Under the glass exterior, the solar panels have a layer for insulation and a protective back sheet, that is going to protect against the heat dissipation and the humidity inside the solar panels. The insulation is quite important because the increase in temperature is going to lead to a decrease in the efficiency of solar energy, resulting in lower performance for the solar panels.