Updated: Jan 14, 2022
Every solar array requires an inverter to con"vert" the DC energy produced by the array into AC, which your home needs to operate safely. DC, or direct current, has its uses, but AC or alternating current is what most home appliances, computers, and other electrical gadgets use. It is the job of an inverter to change the current of electricity from DC to AC, and microinverters or string inverters do an excellent job of making solar energy usable for homes or businesses.
What Is The Difference Between a Microinverter and a String Inverter?
Micro means small, and a microinverter is small. A string inverter controls the energy conversion from a "string" of solar panels. The microinverter handles the energy conversion of just one solar panel, while some options bundle a microinverter to a few panels. Usually, in a solar installation, you have a string inverter for each line of solar panels in the array or a single microinverter for each solar panel. The good news is that technology continues to improve the capabilities of inverters - both micro inverters and string inverters.
The Positives of String Inverters vs. Microinverters
1. Your array may need only one string inverter but will generally need a microinverter for each panel. It can be less expensive to go with string inverters, but generally, that is just the surface cost. Keep reading as we talk more about why microinverters may be a better deal.
2. String inverters generally are less expensive than microinverters since there are few of them, but they also limit power production if there is a problem with the inverter.
3. One or Two connections depending on the number of inverters needed for your system. That means less wiring when you opt for a string
The Negatives of String Inverters vs. Microinverters
If there is an issue with a string inverter, it impacts the power capabilities of the entire grid. If you have two inverters and one of them malfunctions, you lose all the energy from the panels connected to that inverter. Further, because a string inverter handles the power from a string of panels, energy production from one panel drops, the energy production from all panels in the string drops. With a microinverter, if the energy production of one panel drops, it only impacts the energy production for that one panel. If there is a microinverter failure, you will lose the power generated from just one panel. Another negative of string inverters is that it becomes more challenging to expand your solar array. You need to install another string of panels, anew inverter, and then tie both to the existing system. With a microinverter, you can add a single panel or many panels and connect them to the
String inverter warranties last from 8-12 years. A microinverter has a 25-year warranty. Expected replacement is a crucial term for solar array and installation. Microinverters have a much more extended warranty, and that should match the warranty for the solar panel it services. There may
be more cost savings when comparing the expected replacement of string inverters to the initial cost of string inverters over microinverters.
Energy Production Monitoring and Efficiency
With string inverters, you can monitor the production from the inverter but not specifically from each panel. With microinverters, you can obtain efficiency data from each panel; with string inverters, you can get a general idea of the array's efficiency or a string of panels. With microinverters, you can evaluate the energy production of each panel and make adjustments to improve panel performance. With string inverters, the string of panels is limited in energy production by the panel in that string that produces the lowest amount of energy. If one panel in a string produces only 50% energy, all panels will produce only 50% energy. With microinverters, if a single panel drops energy production from 100% to 50%, then it impacts the energy production of just that one panel. The other panels would continue to produce 100 % of the energy.
Which type of inverter is best for your solar array? The answer is dependent upon a few factors, such as shade and direction. Give us a call for more property-specific information!