Project Guide

How Do Solar Panels Work?


Learn how solar panels work and determine if this eco-friendly energy option is a good fit for your home.

1. How Do Solar Panels Work?

A solar panel is made up of numerous photovoltaic cells linked together. The panel is encased in glass with an anti-reflective coating that ensures that the solar panels get the most sun exposure possible. Under the glass, there is insulation that protects the components from humidity and regulates the temperature inside the panel to keep it operating efficiently.

Photovoltaic cells are made of two layers of silicone. The top layer is treated with phosphorus to create a negative charge, while the bottom layer is treated with boron to create a positive charge. When the two layers are placed together, an electric field is created in the space between the positive and negative layers.

Light strikes the panel, causing energy to be transferred to the semi-conductor material which releases electrons.

The electric field in the cell forces the electrons to flow in one direction, creating an electrical current. Thin metal plates on the sides of each cell collect the energy and transfer it to wiring which feeds the DC current into a power inverter.

There are three types of solar cells: monocrystalline, polycrystalline or amorphous.

  • Monocrystalline cells are comprised of a uniform silicone crystal. These are higher-efficiency panels.
  • Polycrystalline cells are made up of different silicone fragments. They are less efficient than monocrystalline cells and work best in climates with a lot of sun but come at a significantly lower cost. Amorphous cells are made from thin, light flexible sheets of photovoltaic film. In a panel, these cells can be combined to increase their power output.
  • Amorphous solar panels are lighter and easier to work with and perform better in areas that get less direct sunlight. While the technology is advancing rapidly, currently they are more expensive than mono- and polycrystalline solar cells and are less durable than either.

2. How Do Solar Panels Work for Your Home?

A household power inverter is a necessary solar power accessory. The solar power inverter converts the DC current sent from the solar panels to AC current which can be used by the appliances in the home.

There are two types of inverters: pure sine wave and modified sine wave. Modified sine wave inverters are less expensive and will run most of the electrical appliances in your home, but some household items will run much less efficiently and some, such as medical equipment and laser printed, should not be used with a modified inverter at all. Pure sine wave inverters are more expensive, but the power they produce allows everything in your home to function just as it would if you were using grid power.

3. How Do Solar Panels Work at Night?

Many people question how solar panels work at night since they obviously no longer have light to generate power. The simple answer is that they utilize solar batteries to store energy.

The home electrical panel is fed by the energy converted by the inverter. However, neither the solar panels nor the inverter have an inherent means of storage. This is why it is necessary to utilize high-capacity, deep-cycle solar batteries as a part of an effective solar energy system.

Deep-cycle batteries are used to store power from the solar panels. During the day, any extra power produced is used to charge the solar battery. Most solar batteries have their own inverters and can store the DC power as AC. At night, the battery sends the stored energy back into your electrical system to power the home electrical panel while the solar panels are not generating energy.

4. How Do Solar Panels Work to Save Money?

solar-powered home is usually still connected to the municipal power grid. Net meters send any excess energy that your solar panels produce – after your solar batteries are fully charged – back into the municipal electrical system. The power company then issues you credit on your electric bill. In effect, they are paying you for the extra power your solar panels generate. In times of low production from your solar panels – night time or extended periods of inclement weather – you can use energy from the municipal grid; your credits offset your energy costs.

After learning how solar panels work, you may be much more interested in adopting the technology. When you are ready to embrace solar power as a means of providing energy to your home, visit The Home Depot and schedule a consultation for solar power installation. The experts at The Home Depot can provide you with everything you need from solar panel kits to solar power accessories.