Updated on August 19, 2025
Are you shopping for a solar system? Probably, right? I mean, you found this article, so you must be at least interested. There’s a lot of information out there that you’ll need to sort through to figure out your specific needs.
A big decision you’ll have to make early on is whether you want to install a microinverter solar system or a string inverter solar system. The inverter debate is always a heated topic of conversation when shopping for solar.
There are advantages and disadvantages to each type of technology. However, the price of each type of system is generally what people look at when making this decision, and what we’re focusing on in this article.
At PSC Energy, we install microinverter and string energy systems. We’re going to give you the honest truth about our products, but please keep in mind that we are a little biased. And we’re going to do it exclusively from a cost/pricing point of view.
In this article, you will learn:
- Microinverters vs. String Inverters: What’s the Difference in Upfront Cost?
- Do Microinverters or String Inverters Last Longer?
- What Costs More to Maintain: Microinverters or String Inverters?
- FAQ: Solar System Cost Differences
By the end of this article, you’ll understand why and how microinverters and string inverters are priced differently from each other.
Microinverters vs. String Inverters: What’s the Difference in Upfront Cost?
When pricing a solar system, the math around calculating the cost is a little different from pricing anything else. There’s the upfront cost of installing the system, which is one price, but there’s also the price of your return on investment. That second price will fluctuate (sometimes significantly) depending on how much energy you use and what type of system you choose to install.
Upfront Cost of Microinverters:
The cost of a microinverter solar system with PSC Energy is based on the size of the system you want.
- A 5 kW system costs about $2.00 per watt.
- A 10 kW system costs about $1.30 per watt.
- A 16 kW system costs about $1.10 per watt.
Because we are an in-house solar installation company, our installation fees are fixed at a day rate.
Any solar system above 36 panels (approximately 16kW) will require a second day to install the system due to its size.
There’s a price jump for installations that are larger than 36 panels, and it’s that second installation day that drives up the upfront cost.
There’s a sweet spot in our pricing that’s a fantastic opportunity to save some money. A string system installed by subcontractors will be cheaper up to a certain point (about 8 or 9kW). But because a subcontractor charges by the panel rather than charging a fixed day rate, as the size of the system increases, so does their installation cost.
Less than 8kW will most likely be cheaper with a string inverter system, but when you go above 8 or 9kW, you get into some intriguing math.
The string system will still be cheaper upfront, but by a much narrower margin. The prices are competitive from 9kW upwards, and better at 16kW.
If your solar system is bigger than 8kW, but will only take one day to install, you’ll be getting a favourable rate for your solar regardless of whether it’s a microinverter system or a string system.
Upfront Cost of String Inverters:
String inverter solar systems have a lower upfront cost. How much lower depends on which solar company you’re getting quotes from. Some solar sales companies are slightly less expensive than ours, and some are considerably lower upfront.
A string inverter solar system that’s of good quality will cost approximately $1.00 per watt, making it easy to calculate the price. String inverter installers usually charge per panel to calculate the installation costs.
- A 5kW system costs about $1.00 per watt, totalling around $5,000.
- A 10kW system costs $1.00 per watt, totalling around $10,000.
- A 16 kW system costs about $1.00 per watt, for a total of around $16,000.
As you can see, a 5kW string inverter system is about half the cost of a microinverter solar system of the same size, but as the size of the system increases, the cost of the installation increases.
Brief Note About Payback Period and Return on Investment: It is a challenge to estimate the payback period and return on investment for either solar system (the second price that fluctuates, which we mentioned above). There are so many variables that will affect this figure.
- What size is your solar system?
- What’s the cost of electricity per kWh from your energy retailer?
- Did you include a solar battery in your system?
- What are the feed-in rates with your DNSP or VPP?
Calculating these figures is best done with the help of a solar consultant, and you should talk to consultants who install both microinverters and string inverter systems to get clear numbers that are useful to you.
At PSC Energy, we consider several things as we figure out what system will save you the most money over time. For a well-designed residential microinverter solar system, the payback period is around 4-5 years. It might be longer if there are any unforeseen expenses in the installation process (additional days = bigger upfront price) or if you add on any additional components (like an AC-coupled battery).
A string inverter solar system may or may not have that short of a payback period. It depends on how well the system performs. We expect it to pay itself off in less time because it costs less to install; however, the efficiency and performance of string inverter systems will often extend this payback period (sometimes significantly).
And remember, as you calculate the cost of electricity over time, the price per kWh from energy retailers is rising quickly. In the past year, we experienced two significant increases in the cost of electricity.
If you’re not self-consuming most of the electricity your solar produces, it will be challenging to keep up with the rising cost of energy from your energy retailer due to inflation.
If you’re interested in learning a bit more about how microinverters compare to string inverters, you might want to check out the following article titled, Microinverters vs. String Inverters: An Honest Comparison.
Do Microinverters or String Inverters Last Longer?
Like everything in life, you get what you pay for, and it will last longer if you care for it. How long your system is expected to last will contribute significantly to the value of your system over time. The longer it lasts, the better bang for your buck.
When it comes to calculating the payback period and return on investment, you must look at the protected and projected lifespan of the solar components.
Microinverter Lifespan:
This is a very important factor to look at when you’re estimating long-term savings from your solar system.
A microinverter solar system installed in Australia has a 25 year warranty on the microinverters themselves.
String Inverter Lifespan:
The warrantied lifespan for most string inverters is considerably shorter than the lifespan of a microinverter.
A Fronius string inverter (the leading brand) will have a warranty of 5 years with an option to purchase an additional 5 years.
Without adding the warranty extension, the string inverter is only certified by the manufacturer to last a fifth of the time a microinverter will (5 years vs 25 years). This means you will replace it multiple times before you reach the lifespan of a microinverter.
If you want your string inverter solar system to last as long as your microinverter solar system, well, I don’t know what to tell you. It doesn’t.
According to the manufacturer, you’ll need to replace it to get it to last as long as a microinverter.
We haven’t mentioned the solar panels’ warranty period. It’s pretty standard for mid-range panels to have a 25 year product warranty and a 30 year performance warranty.
You want an inverter that will last. Your solar panels will.
If you’re interested in learning more about warranties for solar equipment and installation services, you might want to check out the following article titled, A Complete Guide to Solar Warranties.
What Costs More to Maintain: Microinverters or String Inverters?
Microinverter Maintenance Costs:
At PSC Energy, we have a workmanship warranty for service in addition to the manufacturer’s warranty.
If your microinverter solar system stops working or if you have equipment and components that need replacing, PSC Energy takes care of that for you.
String Inverter Maintenance Costs:
We mentioned the lifespan of a string inverter in the previous section, but the timeline for repairs and the cost of getting that inverter repaired varies, sometimes significantly.
Let’s go on a journey together. Here’s a hypothetical situation to consider: a year or two after you installed a string inverter solar system, the inverter stops working.
Did you even notice that your system stopped working?
Time is expensive in the solar industry. If your system stops working, you’re spending money on expensive, grid electricity at over $0.38 per kilowatt hour while it’s offline.
Microinverter solar systems offer energy use monitoring through an app on your phone called Enlighten. At the press of a button, you can know how your system is performing down to each panel.
Enphase microinverters come with this software for free. It’s helpful if anything goes wrong with your solar system.
Of course, some string inverter solar systems also offer consumption monitoring, but because of how string inverter systems work, you don’t get panel-level monitoring without DC optimisers.
For a string inverter solar system without DC optimisers, you’ll probably want to invest in purchasing a third-party monitoring system because most string inverter monitoring apps are limited and can’t report on solar efficiency at the panel level.
Solar Analytics is a popular third-party option for many who invest in a string inverter system. It adds about $800 to your system, and you’ll also have to subscribe to the software (which runs $5.99 per month).
Okay, I know that was a bit of a walk just to let you know that you’ll want to spend an additional $800 on components and software for Solar Analytics to make it closer to the capabilities of Enphase microinverters, but that little investment could save you a lot of money and heartache down the road.
Let’s say you only have the included string inverter system monitoring software and didn’t invest in third-party software because you wanted to save $800. Because of this cost-saving choice, you don’t know when your string inverter is busted. How could you? There are no alerts from an app to let you know when the system is underperforming.
You get a quarterly energy bill. It’s a little high, but it’s summer, and you’ve been running the air conditioning a lot, so you don’t think about it. You don’t know that your solar system is broken.
Then the next bill comes, and it’s enormous. You’ve gone an entire quarter (possibly more) without your solar system working. How big is your electricity bill? Is it over $1,000 per quarter?
Something’s not working. You call the company that sold you the solar system, but they only cover the sales component of the installation process. They tell you that you need to contact the subcontractor they hired to install your string solar system.
Let’s pretend the solar sales company has the contact information for you instead of cutting you loose and letting you track that electrician down on your own (which happens more often than you’d imagine).
You call that subcontractor immediately, but they’re a little busy with other installations. They can’t fit you in for another week at the earliest. And time is expensive in the solar industry.
The subcontractor finds some time in their schedule and goes to your home to look at the system. As we mentioned above, a monitoring app helps diagnose issues with your solar system rapidly and efficiently. If you don’t have that tool, it will be difficult to diagnose the problem.
A $5,000 is now costing $6,000 because of that extra quarter of electricity bills. Every three months, the cost of all of this is extending the length of your payback period.
The subcontractor will probably figure out very quickly that the string inverter is the problem. He’s good at his job and knows it’s a mechanical failure. The panels and the equipment connecting everything to the inverter are all warranted.
The subcontractor reckons it’s the string inverter malfunctioning and directs you to take your claim up with the company that sold you the system. They are responsible for fulfilling warranties.
But the sales company automatically questions if it’s the equipment. They want to verify that it wasn’t an installation error that the subcontractor they hired made instead. Investigating this takes time.
The back and forth between the sales company and the subcontractor is eating up another quarter of electricity bills. You’ve spent another $1,000 on another quarterly bill. How much did that inexpensive string inverter system cost you in total? Now you need to add that $2,000 you just paid in electricity bills to your payback period.
You’re starting to get frustrated with the whole process and decide to file a fair-trade claim, but that takes time to process as well. And you’re going to see another quarterly electricity bill soon. How long does it take the government to resolve claims? If it takes a long time, you’ll be paying for your energy again.
Do you see what’s starting to happen with the cost of the system over the string inverter’s lifetime? Remember when we mentioned that the lifespan of the string inverter is less than the lifespan of a microinverter?
You still have to replace the string inverter to match the lifespan of the microinverter solar system.
And you might go through this cycle again if your next inverter stops working.
The upfront cost for a string inverter solar system is lower. And it’s often significantly lower than the upfront cost of a microinverter solar system.
You will pay more for a string inverter solar system over time.
This can all be avoided by working with an in-house installer like PSC Energy. We hire everyone from solar consultants to electricians to sales, marketing, and installers.
The in-house model prevents our customers from dealing with the warranty run-around. We maintain a service department that exclusively manages problems our customers have with their systems. We respond quickly and resolve issues.
If you’re interested in learning a bit more about solar panels and energy systems, you might want to check out the following article titled, Are Solar Panels Worth It in NSW, Australia? A Price Breakdown for 2025.
Strings or Micros: Connecting the Watts
Now you have a much better idea of what to consider when comparing the overall cost of a microinverter solar system to a string inverter solar system. The price will vary depending on the many factors you need to consider when installing a solar system.
You’ll need to evaluate the upfront costs against the payback period for each type of system. As you collect quotes from string inverter solar systems, be sure to confirm the costs of installation and what kind of warranties a solar installer fulfils.
At PSC Energy, we believe in customer satisfaction, which is why we install the products we install. Microinverters are a part of your solar system that costs more upfront but saves you money long term. A string inverter solar system will save you money upfront, but you risk quite a bit more money long term. The choice is entirely yours; we’re just here to make sure you make the right one for your needs. It’s what we do.
If you’re interested in learning a bit more about solar and battery rebates in NSW, Australia, you might want to check out the following article titled, Ultimate Guide to Australia’s 2025 Solar Rebate and Battery Rebate: Federal and NSW Rebate for Solar.
FAQ: Solar System Cost Differences
What is the difference in upfront cost between microinverters and string inverters?
Microinverters cost more upfront, ranging from $1.10 to $2.00 per watt, while string inverters cost can range from $0.60 to $1.00 per watt.
Are microinverters more expensive than string inverters?
Yes. A 5kW microinverter system can cost nearly twice as much as a string inverter system of the same size. However, as your system increases in size, microinverter costs go down due to economies of scale.
When do microinverter systems become more cost-competitive?
Above 8–9kW, the cost gap narrows. At around 16kW, microinverter and string inverter prices are more competitive.
Do microinverters or string inverters last longer?
Microinverters last longer, with 25-year warranties. Most string inverters only carry 5–10 year warranties.
How many times will a string inverter need replacing?
Over 25 years, you may need to replace a string inverter multiple times, while microinverters usually last the whole system lifespan.
What are the maintenance costs of a microinverter solar system?
Microinverters require little maintenance, and monitoring software alerts you to issues quickly at the panel level.
What are the maintenance costs of a string inverter solar system?
String inverters often cost more to maintain, may fail sooner, and without advanced monitoring, problems can go unnoticed.
Do string inverters need extra monitoring software?
Yes. Panel-level monitoring usually requires third-party software like Solar Analytics, which costs about $800 plus a subscription.
Which solar inverter system has better monitoring features?
Microinverters include free panel-level monitoring. String inverters without DC optimisers only monitor whole-system performance.
Which solar inverter system has a faster payback period?
Microinverters often pay back in 4–5 years. String inverters have a lower cost but reduced efficiency over time.
