String Inverters: Advantages and Disadvantages Explained

Solar string inverters are electrical devices that convert the direct current (DC) generated by solar panels into alternating current (AC) that businesses can use. They are usually installed in a string formation where multiple solar panels are connected in series to form a single circuit.

 

A string inverter is connected to a series of solar panels, collectively referred to as a solar array. A typical solar array consists of approximately 15 solar panels, each with a capacity of 250Wp.  

 

String Inverters and Microinverters  

 

Inverters play a crucial role in any solar power system. They convert the Direct Current (DC) electricity generated by solar panels into Alternating Current (AC), which powers most household appliances. A high-quality inverter enhances the reliability and efficiency of your solar power system, ensuring optimal performance.  

 

There are two main types of inverters available:  

1. String Inverter  

2. Microinverter  

 

 

String Inverters Explained  

 

A string inverter connects to a series of solar panels, collectively referred to as a solar array. There are multiple configurations for connecting a string of solar panels, but a typical solar array often includes about 15 solar panels, each with a capacity of 250Wp.  

 

In this setup, the solar panels are connected in series to the string inverter. The inverter aggregates the Direct Current (DC) electricity generated by each panel and converts it into Alternating Current (AC) in a single operation.  

 

The number of solar panels that can be connected to a string inverter depends on the inverter's input voltage rating, which determines its capacity to handle the combined output of the solar array.  

 

Advantages of Using String Inverters  

 

String inverters are the most widely used type of solar inverter, known for their robustness, durability, and decades of proven performance. Their popularity stems from their reliability and the fact that, until recently, few alternatives were available on the market.  

 

Ease of Maintenance and Troubleshooting  

 

String inverters are typically installed in a central location, such as a utility room or mounted on a wall. This centralized setup makes maintenance and troubleshooting much easier, as there’s no need to visit the solar panels in the field. This convenience is especially valuable in areas with extreme weather conditions, whether cold or hot.  

 

Trusted Technology  

 

Having been in use for decades, string inverters are a trusted and well-understood technology. Their reliability is widely recognized, and electricians are generally familiar with their design and operation, ensuring seamless installation and servicing.  

 

Lower Costs  

 

String inverters are more cost-effective compared to microinverters. A single string inverter can manage the output of an entire solar array, whereas microinverters require one unit for each individual panel, significantly increasing overall costs.  

 

Disadvantages of String Inverters  

 

Single Point of Failure  

 

One major drawback of string inverters is their single point of failure. If the inverter malfunctions or breaks down, the entire solar array becomes inoperable, resulting in a significant loss of electricity production until the issue is resolved.  

 

Limited Expandability  

 

String inverters offer limited flexibility for future system expansion. Unless an oversized inverter is initially purchased, upgrading the solar array requires adding a separate inverter, as the capacity of an existing string inverter cannot be adjusted to accommodate additional panels.