There are many parts of a solar system, and it's important to pick the right pieces so you can get the best quality and efficiency for your home. Inverters are a necessary staple in any solar installation. Afterall, you wouldn't be able to use any of the electricity your panels produce without going through an inverter first.
Solar panels turn the sun's energy into DC current, which needs to be converted into AC current to be used by your house. We use inverters to do just that. There are two common types of inverters—string inverters and microinverters.
At Polaron, we use microinverters for all our systems. Let's look into the differences between the two to better understand why we decided to go with microinverters instead of traditional string inverters.
How do They work?
String inverters are a single box installed near your main service panel and electric meter. String inverters link your panels in a series, usually connecting 6-12 panels together. Depending on the size of your solar system, you'll need 1 or 2 inverters installed.
Microinverters are much smaller and installed underneath each individual panel, linking them in parallel. You'll typically have as many microinverters as there are solar panels in the system, although some microinverters can be connected to 2-4 panels at once.
When it comes to safety, microinverters are the clear choice. Microinverters make sure DC never exceeds 60V on your roof, whereas string inverters can go up to 600-1000V. This is because microinverters convert raw power to safe energy at the micro-level, ensuring no high voltage is running on the roof at any time, significantly reducing the risk of fires. Rapid shutdown is also already implemented in every inverter, making it easy to shut off in case of emergency.
Because string inverters connect panels in a series, if one goes down or produces less energy, every other panel in the series is also affected. This is especially an issue if partial shading of your panels is happening throughout the day, as the entire system will only perform as well as the lowest producing panel.
On the other hand, microinverters connect in parallel, which ensures that all your panels are working independently and at the highest efficiency.
Microinverters also make it easy to monitor each panel's performance. Monitoring Apps and web clients allow customers to see individual panel production. It's easy to use and provides all the information you need about your system.
On the other hand, troubleshooting a string inverter is pretty straightforward since it is the only inverter. The installation location also makes it easier to repair if there's ever a problem.
On average, string inverters cost less than microinverters because there's usually only one, and therefore, less hardware needs to be purchased overall. However, it's important to note that if you live in an area that requires rapid shutdown in case of fire or other emergencies, there might be additional costs for a rapid shutdown box that will need to be installed near the electrical service entrance.
Why do we use Microinverters?
Looking at all the facts, why did we choose to install microinverters? We wanted to combine highly efficient power with user-friendly monitoring to bring you reliable, safe and sustainable energy. Our proprietary system architecture increases solar harvest and ensures maximum output for your PV arrays.
Comparing Solar Microinverters Vs. String Inverters | Enphase
Micro Inverter vs String Inverter: 13 Factors to Consider (greencoast.org)