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SMA Sunny Boy vs. Fronius Primo | Inverter Comparison 2023

Updated: Nov 23, 2023

The inverter is certainly one of, if not the most, critical components of the solar system.

When it comes to good quality, premium solar inverters, SMA and Fronius are both industry leaders. They have both been manufacturing inverters for more than 20 years and have a solid reputation in Australia for producing reliable, efficient and long-lasting products.

So, which one should you choose? While we install and recommend both the SMA Sunny Boy and Fronius Primo to our customers, there are a couple of important points of difference. This article compares their key features, important statistics and our tips to help you make a decision.


SMA Sunny Boy 5kW

​Fronius Primo 5kW


​Single-phase, string inverter

​​Single-phase, string inverter


​10 years parts & labour

​5 years labour/10 years parts



​98.1 %


​German engineered. Made in China



​435 x 470 x 176 mm

​645 x 431 x 204 mm





​5000 VA

​5000 VA


​17.5 kg

​21.5 kg


​IP 65

​IP 65


​‒25°C to +60°C

​-40°C to +55 °C


SMA Sunny Boy

Fronius Primo

Compact, distinctive design means minimum space requirements

Safety in Numbers – More than 500,000 Fronius inverters have been installed across Australia.

Quality German engineering and design SMA is the number one European PV inverter manufacturer brand.

Warranty Support – The Melbourne office of Fronius provides competent backup and support.

Extensive Testing Every SMA inverter is comprehensively tested before it leaves the factory.

Manufacture with Selective Focus – Fronius do not try to be “All things to all men”. The business has 3 main areas of focus–photovoltaics (including inverters), battery charging and welders. The Fronius name represents outstanding quality and reliability in all 3 divisions.

Impressive Track RecordSMA has been manufacturing inverters for 40 years, making SMA the world’s longest solar inverter manufacturer. With more than 750,000 SMA inverters installed across Australia alone, SMA inverters produce more than 35% of all solar electricity in our country.

Performance Beyond ReputeFronius inverters are globally recognised as amongst the industry’s highest-performing inverters. Their performance and reliability are undeniable with a failure rate of just 0.5% (source: Nexergy .solar) and 98.1% maximum efficiency. Impressive Track Record – Fronius was established in 1945 and has been

Higher Yield Thanks to Minimizing the Impact of ShadingSMA ShadeFix technology is built into the inverters at no additional cost. It increases the energy production of a solar power system under standard shading light to medium shading conditions.

Impressive Track Record – Fronius was established in 1945 and has been manufacturing solar inverters since 1994. A history spanning more than 2 decades with 28 subsidiaries across 4 continents.

Round the Clock Peace of Mind MonitoringSMA Smart Connected is a free and automatic inverter monitoring service performed automatically by SMA.

How to choose which one is best for you

Do you have reliable, permanent internet where the inverter will be installed? 
  • No We’d recommend a Fronius inverter.  Most Fronius residential inverters (apart from the new Gen24 models) have a screen on the front so you can see what the system is producing by looking at the inverter without having to rely on an internet connection.

  • Yes → We’d recommend an SMA inverter. SMA inverters do not have a screen on them, which means that to monitor the system, you need to use an app via the Internet. If you do not have a reliable internet connection with an SMA inverter, you won’t be able to see how your system is performing.

Do you want to/are you comfortable using a monitoring app?
  • If you’d like to use an app → We’d recommend an SMA inverter. SMA‘s free monitoring portal and app allows you to see how your system is performing quickly and easily even when you aren’t at home.

  • If you’d prefer to look at the inverter screen → We’d recommend a Fronius inverter. For people who aren’t as tech-savvy, or would just prefer to go out and look at the screen on the inverter, the Fronius Primo would be better. The screen can show the following data: output data, grid voltage, output current, grid frequency, solar module voltage, the solar module current plus more!

Do you have any potential shading? 
  • Yes → We’d highly recommend the SMA Sunny Boy. The SMA Sunny Boy has built-in ShadeFix Technology to optimise production in partially shaded conditions. If you have trees, buildings or structures nearby that could cast a shadow on the roof, we’d recommend taking advantage of SMA’s innovative ShadeFix Technology. 

  • No → The SMA Sunny Boy or Fronius Primo inverter would both be suitable.

Still can’t decide? Here are some other things to consider
  • Aesthetics. The SMA Sunny Boy has a distinctive red design. Some customers prefer the Fronius Primo because its grey design is more subtle which blends in better.

  • Cost. The SMA Sunny Boy is slightly cheaper. They usually work out to be around $150 less than the Fronius Primo for a 5kW.

  • Size. The Fronius Primo comes in a larger range of sizes (3.0 and 8.2kW) compared to the SMA Sunny Boy which comes in 3.0 to 6.0 kW. 

At the end of the day, it really comes down to personal preference – they are both good quality inverters that should perform well for a very long time. 

At Electrical Sensations, we are proud to have been servicing Toowoomba and the Darling Downs since 2004. We are 100% committed to designing energy-saving solutions and installing high-quality equipment that will best meet your needs, in a manner that we are proud to put our name to. No cutting corners or compromising on quality, reliability or safety. Please don’t hesitate to contact us, we would love to help you save money oGerman-engineeredn your electricity bills!


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