Have you ever wondered about the different parts that make up a home solar system, and how they work together to make it all possible? If so, you’re not alone.
A home solar system is much more than the solar panels on a roof – there are many parts of a home solar system that must all work together to produce solar energy.
If you’re considering joining the hundreds of thousands of other homeowners who have already gone solar, an important first step is understanding all the different components that will make up your home solar system.
The good news is, you’ve come to the right place. Below, you’ll learn about the different home solar components and the role each one plays in helping you harness the power of the sun.
We’ll start with the most obvious piece of the puzzle: the solar panels. Also known as photovoltaic (PV) panels, this is where the solar process begins the conversion of light into electricity.
Solar panels are made of silicon cells covered in glass. There are two main types, and the difference between them comes down to how the silicon is applied to form the cells within each panel.
- With monocrystalline panels, solar cells are made using silicon that is formed into bars and then cut into wafers. The name “monocrystalline” comes from the fact that single-crystal silicon is used in this type of panel construction.
- With polycrystalline panels, rather than use a single crystal of silicon, multiple fragments of silicon are melted together to form the wafers of the panel. Hence, the prefix “poly” – although polycrystalline panels are also sometimes referred to as “multicrystalline.”
Monocrystalline and polycrystalline solar panels both serve the same purpose: converting the sun’s power into energy. However, since the cells in monocrystalline panels are composed of only a single silicon crystal, the electrons that generate the electricity have more room to flow. As a result, they tend to be more efficient than polycrystalline panels.
The higher efficiency of monocrystalline panels usually makes them the more expensive choice for solar panels, but both options have an expected lifespan of 25 years or more. Your installer can help you determine which type of solar panel is right for your home.
A solar array is the name for multiple solar panels arranged together. So, all the solar panels on your roof make up a solar array.
The size of a solar array will depend on many factors, such as geographical location, roof pitch and your energy needs.
Solar Panel Mounting System
Although the solar panels are arguably the MVP (most valuable part) of any home solar energy system, the mounting system is what attaches your panels to your roof. There are primarily two configurations, and the one your installer uses will depend on the type of roof you have.
Roof-penetrating solar racking has been used since the inception of solar. This type of mounting requires installers to drill holes in your roof to secure the racking system in place.
- Roof-penetrating solar racking is better suited to traditional or composite asphalt rooftops.
- Reputable installers will take great care in sealing the area around your racking equipment to prevent leaks; they should also provide you with a warranty that covers leakage.
- Some installers may offer mounting options that attach directly to your roof, which are usually faster to install and more aesthetic.
Specialized solar mounting systems provide an alternative to roof-penetrating racking.
- This is ideal if your home’s roof is made of a more unique, less traditional material that could be compromised if holes were drilled into it.
- Spanish or clay tiles and metal are among the roof types that are better suited to a specialized mounting solution.
- Clamps and metal mounts are strategically fitted to certain sections of the roof where they blend in with the roof material so that the solar system can be installed while preserving the beauty of the roof.
The inverter converts the direct current (DC) electricity from your panels into alternating current (AC) electricity that your home’s appliances can use. There are three main types of inverters available, and the best one for your home depends on how your solar array is configured:
- String inverters have been around the longest and are usually the most inexpensive option. This type of inverter is installed at ground level and may be a good choice if your solar panels aren’t subject to shading or don’t face in multiple directions.
- Microinverters offer the latest technology and are ideal for complex solar installations, such as those with solar panels that experience some degree of shading or face in different directions. Unlike string inverters and power optimizers (below), microinverters are installed behind each solar panel or as part of the panel site.
- Power optimizers are also better suited to more complicated solar projects; however, they are more cost-effective than microinverters. Often considered a “happy medium” between string inverters and microinverters, power optimizers are installed at ground level.
Your installer will help you choose the right type of inverter and install it properly according to local building and electrical codes. And sometimes, a combination of inverters may be recommended for your solar system.
For even greater energy control and the added security of a backup power source during grid outages, you should consider adding a battery to your home solar system. The way your battery is linked, or “coupled,” to your solar system will largely be determined by the age of the system.
- DC coupling: Newer solar systems typically come with a battery-ready inverter, also known as a hybrid inverter. What makes it a hybrid is that it’s shared by both your solar panels and your battery. Since both components operate in DC power (your panels produce it and your battery stores it as such), your solar array can be directly connected to a DC-to-DC converter, eliminating the need for a second inverter specifically for the battery.
- AC coupling: Older solar systems generally require an additional inverter to connect to the battery since the original inverter installed with the system likely won’t have hybrid functionality. This simply means your solar panels and your battery are both connected to AC-to-DC converters, which feed into the two inverters to produce usable AC power.
So, regardless of when your system was installed, you can make the most of the energy it produces by adding the storage capabilities of a battery.
Utility and Solar Meters
You’re probably familiar with a traditional electricity meter, which is what your utility company uses to measure your energy usage each month. But when you go solar, you will either need to replace your traditional meter or add a second one to measure how much solar energy you produce and send to the grid.
There are three main types of solar meters:
- Net meters display your home’s net energy consumption but won’t show you how much energy you send back to the grid. This type meter will replace your traditional meter and is an option in utility markets that allow for net metering.
- Bi-directional meters feature three different display screens. The first one is a test screen; the second one shows the amount of power you’re receiving from the grid; and the third screen tells you how much power you’re sending to the grid from your solar system. Similar to net meters, bi-directional meters also replace the traditional utility meter and are used in net-metering utility markets.
- Dual meters are what they sound like: two separate meters that don’t communicate with each other. This means you keep your traditional meter, but a second “production meter” is added to measure the amount of solar energy you send to the grid.
For safety reasons, your solar system should include a disconnect switch that allows it to be turned off for repairs or maintenance, or during other rare occasions that would warrant an absence of power.
Some grid-tied solar systems have two disconnect switches: one that disconnects the DC current that flows between the panels and the inverter, and another one that disconnects the inverter from the grid.
Putting It All Together
Six years and nearly 60,000 customers later, we have making the switch to solar down to a science. With Sunnova, we make going solar easy with a variety of products and financing options to fit your needs. Our teams of local installation partners and service experts will have a strong understanding of your local solar needs.