Central Inverter vs. Microinverter PV Systems: Advantages and Disadvantages

While discussing solar systems, both central inverter and microinverter PV systems are a great way to harness solar energy to power your home or business, but it’s always good to know the advantages and disadvantages of each before making your final decision on which system to go with. This article will cover the pros and cons of both systems, so you can figure out which one works best for you.

What are Central Inverters?

A central inverter is an electronic device that converts DC (direct current) electricity from solar panels into AC (alternating current) electricity, which is then fed into your electrical panel for distribution throughout your home. They are typically floor or ground-mounted, as opposed to string inverters, which are usually installed on wall mounts. These devices are generally more expensive than their micro-sized counterparts, but they also offer a few key advantages over micros. They are in the range of a few kilowatts to megawatts.

Advantages of Central Inverters

  • Central inverters require less wiring complexity than multiple smaller inverters, making installation easier.
  • Central inverters can handle more power than microinverters.
  • Central inverters are more efficient at converting DC to AC than microinverters.
  • They are installed inside the home hence protected by weather conditions.
  • They have fewer harmonic contents, fewer dc components, and deliver higher power quality.
  • Less expensive with respect to $/W, when compared to microinverters for similar power ratings.
  • They have fewer installation issues when compared to micro inverters due to straight and simple wiring involved in the installation process.
  • Ability to produce much higher power, ideal for larger installations (10kW+).
  • Old Technology so maintenance is not complex.

Disadvantages of Central Inverters

  • A central inverter can only handle a certain amount of solar panels before it becomes overloaded, which means that you may have to install more than one inverter if you have a large array.
  • There is a potential for a single point of failure, which means that if one panel goes out, you may lose power to all of your panels. Hence there are chances of a sudden power failure.
  • A central inverter can be more expensive than a microinverter so there is a higher replacement cost in case of a major failure.
  • Operates on high rating so more safe practices are required.

What are Microinverters?

Microinverters are small but high-tech inverter modules that are installed on each panel separately. Each microinverter works independently to convert DC power from solar panels into AC power, so they are not connected in series or parallel with other microinverters. All microinverters perform independent monitoring and control functions.

Advantages of Microinverters

  • Malfunctioning of a single panel won’t affect other panels in that string, making maintenance easier.
  • They are safer to operate due to low voltage ratings.
  • Microinverters enable better control over voltage at each panel, allowing for more consistent power output from your solar array.
  • Panel level monitoring is easy with microinverters, making it easier to pinpoint issues with specific panels.
  • Microinverters can be installed on existing systems, making them a great option for retrofitting older installations that use central inverters.
  • Simple to design because it is a modular system. Strings calculations are not required in this case.

Disadvantages of Microinverters

  • Cost of microinverters is higher as they are counted as premium products, especially when using high-efficiency modules such as SunPower, and Panasonic.
  • Microinverters require more maintenance costs as they are multiple devices, each with its own monitoring system.
  • This Technology is not as mature as central inverters, so it is difficult to find skilled technicians to repair microinverters.
  • Advanced features require an internet connection, which is not always available in remote locations.