roof with solar panel

What are micro inverters and are they worth it?

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Installing solar panels? Then it’s likely you’ll need to choose which type of inverter you want. In this Canstar Blue guide, we discuss one of your options – the micro inverter. We’ll explain what it is, how it differs from other inverters, and highlight the pros and cons.

Solar panels generate energy, but not in a form that can be directly used in a household. Hence, the need for an inverter. An inverter essentially takes the power generated by the panels and turns it into a useable form. Without this, your home solar system would be effectively useless.

There are a number of inverters to choose from when installing solar panels, such as battery inverters, hybrid inverters, grid-tie and off-grid inverters. Each type benefits the system in a unique way so it is important to understand your energy usage first before making a decision. Typically, however, most households will need to choose between these two options; string or micro inverters.

In this Canstar Blue guide, we will be focusing on the latter – micro inverters. We’ll outline what a micro inverter is, how it differs from a string inverter and whether it’s worth having installed.

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What is a micro inverter?

A micro inverter is an inverter that is installed on solar panels to convert the direct current energy (DC) generated by the panels into alternating current (AC) electricity for use in the home. They are about the size of an internet router and one is installed underneath each solar panel.

The main advantage of a micro inverter solar system is that it can measure the generation of each panel independently as opposed to managing all panels at once.

What is the difference between micro inverters and string inverters?

micro inverter under panel

The key difference between micro inverters and string inverters is that micro inverters are installed on each individual panel, whereas string inverters use just one system for all panels – typically installed away from the panels either outdoors or indoors (depending on the model).

Theoretically, micro inverters should yield more solar power. This is because when solar panels operate in a ‘string’ with string inverters, the current is reduced to that of the lowest-producing panel in the system. Micro inverters, on the other hand, produce energy independently of their neighbouring solar panels. This makes micro inverter solar systems the more attractive option when it comes to combatting shaded areas or the impacts of low light. This is because only the covered panels’ generation is compromised, as opposed to the entire system’s performance.

Micro inverters also tend to operate at a lower voltage than string inverters.

How is a micro inverter different to a power optimiser?

A power optimiser is similar to a micro inverter, in that it is a small box installed directly onto each solar panel. However, instead of being an inverter in its own right, it works alongside a string inverter to maximise the amount of energy collected from each panel. Essentially, a power optimiser is in between a string inverter and micro inverter.

Some panels have power optimisers built in, but others are sold and fitted separately. They work to lessen the impact of one panel underperforming. Unlike micro inverters, power optimisers do not convert DC to AC, but rather ‘optimise’ the DC energy before it is sent to the string inverter.

How much does it cost to install a micro inverter?

Micro inverters tend to be more expensive than string inverters to install, costing between $4,000 and $11,500 on average for an installation. This is because there is more wiring and equipment involved with micro inverters as there is one system per panel – or in some cases one system per every two to four panels. With a string inverter, only one system needs to be purchased and wired for all panels.

Power optimisers are also cheaper than micro inverters, but more expensive than a stand-alone string inverter.

What are some of the benefits of a micro inverter?

Micro inverters come with a hefty price tag so it is important to consider whether the benefits are worth it. Below we’ve listed some of the key advantages of using a micro inverter solar system:

  • Allows for a more flexible panel layout and expansion
  • Allows for panel-level monitoring and optimisation
  • No single point of failure, meaning that if one panel doesn’t work then it doesn’t stop the rest of the panels from performing and providing the household with power
  • Generally come with longer warranty periods than string inverters – usually 25 years as opposed to eight to 12 years

What to be cautious of with micro inverters

money on solar panel

While there are some benefits to installing a micro inverter, like anything, there are also a few things to be cautious of – namely the upfront cost and maintenance. Being on the roof directly instead of on the side of the house means that micro inverter systems run a slightly higher risk of weather damage. As such, it is important to ensure that these systems are installed properly and with the utmost care. Keeping the system regularly maintained will also be crucial, to ensure all parts are still running at maximum capacity.

The higher upfront costs are also something that will need to be considered. Being that multiple systems need to be purchased to fit out an entire solar panel system, the cost of installing micro inverters often ends up to be much larger than that of a regular string inverter.

Solar Plans & Prices

Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Ausgrid network in Sydney but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 3911kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.

Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Citipower network in Melbourne but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.

Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Energex network in Brisbane but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4613kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.

Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on SA Power network in Adelaide but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4011kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.

Are micro inverters worth it?

If you have solar panels, or are looking to get them, you’ll need an inverter. Whether you get a string inverter, micro inverter or one of the other kinds of inverters on offer completely depends on your preference and set up. If you have partial shading from trees or other obstructions, or are likely to expand your solar system in the future, a micro inverter system might be the way to go – granted you can foot the upfront costs.

Otherwise, a string inverter will effectively do the same job. At the end of the day, an inverter’s main purpose is to convert the energy produced by the solar panels into electricity that can be used in the home. Both a micro and string inverter can achieve this – just through different functions. It’s just a matter of assessing what your main energy needs are and picking an inverter that would best fit those needs.

Best Home Solar Inverters

Image credits: Horvath82/Shutterstock.com, Illumina Design_PR/Shutterstock.com, alphaspirit.it/Shutterstock.com

Kelseigh Wrigley
Energy Specialist
Kelseigh Wrigley covers Australia's retail energy market, growing her industry specific expertise over the last 2 years. She holds a Bachelor of Journalism at the Queensland University of Technology and has contributed her skills to online publications Hunter & Bligh and local radio station 4ZZZ.

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