Turning sunlight into clean energy sounds quite magical, especially here in Phoenix, Arizona where we experience nearly 300 days of sunshine annually. That's a lot of power available to any homeowner interested in saving money while providing security against an aging and outdated energy grid. And let's not forget the positive environmental impact.
But how, exactly, does a solar energy system turn sunshine into energy?
Whether you're just starting your research into solar, or have already done quite a bit of investigating, this is one of the most common questions we receive across the board. Most people know that solar panels turn sunlight into energy for your home, but what actually makes that happen and how does it offset what you purchase from the utility?
This is a fair question since a solar energy system is a robust and sometimes mysterious piece of technology. Indeed there is an intricate process happening in and around your solar panels. Let's take a deeper look at what it takes to become your own power utility.
What Makes Up a Solar Energy System
To begin answering the question of how a solar energy system works, we first need to take a look at the components that make up the system. There are three basic components that do the majority of the work.
These turn sunlight into direct current (DC) electricity. Solar panels are comprised of silicon solar cells, also referred to photovoltaic (PV) cells.
This converts the DC electricity into alternating current (AC) electricity for your home.
This is a special meter for solar that monitors energy consumed and energy produced. In other words, it runs in both directions, showing how much power you purchased from the utility, as well as how much you sent back. In that way, your solar meter is especially important for knowing exactly how much energy you're using from your own array versus what the power utility will charge you for on your next bill.
A battery will store any excess solar energy for use at night, or to further offset expensive on-peak rates. A battery also adds security to your home during power outages.
How The System Components Work Together
The whole process of turning sunlight into energy begins the moment sunlight hits your panels and is absorbed by the PV cells. Within the solar cell are semiconductor wafers, one positively charged and one negatively charged. When the sunlight enters the cell, it energizes the cell and results in the electrons separating from the silicon atoms in the cell. This results in an electric current - specifically direct or DC current.
The DC current is captured by special wires within the solar cells that also transfer the captured power to the solar inverter. Because most homes use alternating current or AC energy, the DC solar energy needs to first be converted before you can use it. This is what happens inside your solar inverter. The converted AC energy is the same kind you would get from the grid, so nothing in your home needs to be updated or changed in order to power your home with sunlight.
Producing solar energy happens during the day for obvious reasons, but if you have a battery installed, excess solar energy can also be stored for later use. Today's batteries can be programmed to discharge stored solar energy at specific times, such as during expensive on-peak hours or at night after the sun goes down. A qualified solar installation company can walk you through typical battery configurations to determine which one would be best for you.
The solar meter monitors the flow of energy to and from your home. This is important because on some days you might use more energy than your panels are producing. On cloudy days, for example, your solar array will still produce power, but not as much as a sunny day. This may require you to pull power from the grid, or from an attached battery. Alternatively, on super sunny days when your panels are producing at peak efficiency, you may wind up sending excess energy back to the grid. Some utilities offer a credit for excess solar energy. A solar meter will show you exactly which direction the power is flowing.
Below is a good illustration of how the whole system works together with your home and the utility.
If you're interested in learning if solar is right for your home, we invite you to download a copy of our free guide, "Are Solar & Batteries Right For You?" In it, you'll learn the various factors that make up a solar and energy storage purchase. Or if, you're ready for a free, no-obligation solar quote, simply click the button below to speak to one of our experienced solar integrators.