String inverters are one of the most common types of solar inverters used in residential solar applications. Given their popularity, you might assume that they’re the best choice. However, they’re not the best choice for everyone. Based on your system design and your personal preferences, you might prefer a different type of solar inverter. This article will discuss the primary pros and cons of using a string inverter so that you can decide if it’s the best option for you.
What Is a String Inverter?
First, it’s important to understand exactly what a string inverter is. This type of solar inverter requires all of the solar panels in your solar array to be connected in series, much like a string of Christmas lights. The string inverter combines all the direct current it receives from the solar panels and converts it all into alternating current at the same time.
Pros of String Inverters
So what are the advantages of converting the power in this way? Here are the main ones:
- Easy maintenance – String inverters are usually installed on a wall of your home, making them easy to get to when you need to perform maintenance or troubleshoot any problems in your system. Other types of inverters may require you to climb onto the roof, which is hardly convenient.
- Proven technology – One reason these inverters are popular is that they’ve been around for decades, so people trust them. String inverters are reliable, and electricians understand them fairly well.
- Lower costs – String inverters are often cheaper than other types, like microinverters, since you only need one string inverter for your entire array.
Cons of String Inverters
Of course, every choice has its disadvantages as well. Here are a few of the drawbacks to string inverters:
- Single point of failure – As mentioned, string inverters require the panels to be connected like Christmas lights. So, like a strand of Christmas lights, if one of them goes out, it affects the entire string of solar panels. With some other types of inverters, loss of productivity or even a total breakdown in one panel only impacts that panel. But with a string inverter, even shading on one panel can drag down the rest of the array.
- Ability to expand – Many people who install solar want to get the bare minimum now, then expand their system later when they have additional funds for it. This can be difficult to do with a string inverter. String inverters are rated for a certain input voltage, which determines the number of panels that can be connected to them. Unless you buy a very oversized inverter from the beginning, adding panels to it will be very difficult in the future; you’ll likely have to buy a new one.
If you decide that a string inverter is the right choice for you, the Fronius Primo is a top option to consider.