Micro Inverters Vs. String Inverters: What You Need To Know

As you’re shopping for solar panel systems that best suit your household’s needs, you’ll start to notice that you have a choice in the type of inverter to install with your panels. Most solar panel companies will give you a choice between the two main types of inverters we’re going to talk about today, which are micro inverters vs. string inverters.

What are solar inverters?

The inverter is a VIP of your solar system. A solar inverter is responsible for converting the electricity from your panels into power that can be used in your home – pretty important. Basically, you need an inverter to change the electrical current of your system from direct current (DC) to alternating current (AC). AC power moves in both directions along a wire, forward and backwards. This way, power can flow from your panels to the outlets in your home. Electric utilities are set up to use AC because it can easily be sent long distances can easily be changes between higher and lower voltage levels…fun fact.

String inverters

A string inverter can also be referred to as a central inverter; so don’t be confused if you see these terms used interchangeably. These are the most common inverter options chosen for solar systems, mainly because they cost the least. All of your panels are connected to this single inverter in this case, which is typically mounted on a wall by the main AC panel. This option is also favorable because it creates a centralized system with minimal labor required.

Something to keep in mind about string inverters, however, is that they use Maximum Point Power Tracking (MPPT) to deliver the most power available. This means that since your solar panels will be arranged into “strings” that feed the power into a single inverter circuit, power output from each panel affects the other. And since each panel can generate different levels of power due to shading, clouds, and such, this can be a disadvantage when it comes to drawing the full amount of power. If one panel is temporarily shaded, the system can lose up to 30 percent of its output potential. Because of this, the string inverter is best for a roof that is not shaded at any point during the day and faces only one direction.

String inverters typically last for around 12 – 15 years, while your panels will probably last about 25 years. Thus, you will need to replace the inverter at least once during the system’s lifetime. 

Micro inverters

Micro inverters are the new kid on the block in the solar power marketplace, and their popularity is growing quickly. The cost of a micro inverter is higher but is expected to decrease as they become more conventional. These solar inverters are so well liked because they convert electricity at the panel level without the need of central inverter, so you’ll have one at each panel. The advantage to this system is that micro inverters alleviate the issue of shading because it converts the energy at each panel individually. Micro inverters are also helpful in identifying your efficiency of solar panels since you can easily single out which panel may be underperforming by its dedicated inverter. Another bonus is that micro inverters last longer and typically come with a 25-year warranty.

Ready for the disadvantages? Cost is definitely something to consider. You’ll be paying more for the same-sized system that could be covered with a string inverter. And the more panels, the more inverters needed, so that cost can really add up. Luckily, prices are falling, so if you’re looking to invest in solar in the next few years, this may be a great option. These are also a little more labor intensive to install, which is something to think about if you’re buying them separate from your solar panels.

There are many solar energy advantages, and obviously, there are lots of pros and cons to consider when it comes to solar inverters. Depending on your budget, size of your system, and discussing with your solar panel company, you’ll be able to come to the best choice for your household. Reach out to solar companies in your area for a free consultation and quotes by filling out the short form below.