Solar 101: How Do Solar Panels Work?

12 Jun Solar 101: How Do Solar Panels Work?

Solar energy is one of the most abundant sources of energy in the world and is among the cheapest options for powering your home or business. The sun emits 173,000 terawatts of solar energy, which equates to 10,000 times more than the entire world’s electricity demand. Thankfully, there are a few ways to harness the sun’s rays and turn them into usable energy. The most common, and the one ACE Solar specializes in, is solar photovoltaics (PV) which is the process of converting light into electricity. For those interested in learning more about how it all works, we created this quick explanation of what’s really going on inside your solar panels.

What’s in a solar panel?

A full solar panel is comprised of many smaller units called solar cells, which are made of two layers of crystalline silicon. One layer is mixed with boron to make a positive (P-type) semiconductor and the other layer is mixed with phosphorus to create a negative (N-type) semiconductor. The silicon cells are enclosed in a glass case with a metal frame, most commonly made of aluminum, and electrical wiring is used to transport the energy generated. All of these materials are non-hazardous and are completely recyclable.

How does it work?

The P-type and N-type silicon layers create an electric field that separates electrons from the incoming sunlight, making it possible to mobilize those electrons into a flow of electricity. That flow is then conducted by the metal parts of the panel to be carried through wiring and distributed as electricity. Barring any physical damage, solar panels can last for decades because the only moving parts are the electrons themselves.

What about the other components?

Inverters: Solar energy creates DC (direct current, like a battery) that must be converted into AC (alternating current, what’s typically used in homes) in order to be connected to the electric grid. This is where the inverter comes into play. The inverter will not only convert DC to AC, but it also maximizes the output of power, interfaces with the electric grid, allows for monitoring of system production, and ensures the solar system is functioning safely.

Utility Meter: A utility meter will measure how much electricity the house draws from the grid when the solar panels are not producing electricity. The meter will also measure how much excess energy from the solar array is produced by the home and distributed back to the grid. In states that utilize net metering (such as Massachusetts), the utility company will purchase excess energy that the solar panels produce throughout the day and will charge for the energy they take from the grid. This makes it so electric bills are extremely low or, in some cases, no cost at all to a solar system owner.

Batteries: Storage is an optional component that can be installed and paired with a solar array. There are several ways to store energy such as flywheels, pumped hydroelectric storage, and batteries- to name a few. The most common form of storage is lithium ion batteries. Battery storage undeniably compliments renewable energy. Solar panels gather excess energy during the day. Without storage, that excess energy is sold back to the grid and lowers the electric bill. With storage, the energy is saved and can be utilized at night. In power outages, storage kicks in and can be used when the house would otherwise be out of power.

We hope this gives you an understanding of how a solar system works to provide energy for your home or business. If you have any questions about how it works or are considering solar for yourself, we’re happy to help. You can request a free estimate or schedule time for a call to discuss your options, and we’ll get you the answers you need.

Keep on shining,

Colby Lawless
ACE Solar Intern