The solar inverter is vital for your solar power system, converting the sun's energy into usable electricity. Its lifespan often mirrors its warranty, typically ranging between 5-10 years, though some premium brands like SMA and Fronius have inverters that have lasted over a decade.
Cheaper solar inverters may fail earlier; for instance, many bought between 2010 and 2012 needed replacements by 2014. If repair is necessary, a technician might take the solar inverter, leaving your solar system non-operational. Quality microinverters and optimisers, like those from Enphase, can last over 10 years in hot climates.
Solar inverters usually fail from prolonged exposure to heat; installation in cooler locations can extend their life. Upgrading is sometimes more cost-effective than repairing old models.
How long should you expect your inverter solution to last?
At the heart of any solar system lies the inverter. This key device transforms the direct current (DC) generated by the solar panels into an alternating current (AC). AC power is usable by the majority of appliances in your home. Therefore, you want a high-quality solar inverter that lasts a long time. But just how long do solar inverters last, and what about optimiser or Enphase microinverters?
How long do solar inverters last?
Looking at the warranty of a product can be one indication of how long you should expect it to last. Typically, most quality solar inverters are engineered to work between 10 and 15 years. However, certain premium models, installed in a shady location might exceed this.
With technological advancements, we can expect even longer lifespans from newer solar inverter models. Some solar inverters have warranties of up to 15 years. For these products, you will be paying more of a premium.
The saying you get what you pay for definitely applies to solar inverters. When searching for a solar system with an inverter, you might find some at enticingly low prices. Yet, many individuals who bought and installed these inexpensive solar inverters had poor experiences. When these came onto the market the 1st time between 2010 and 2013 many purchasers found themselves needing replacements only 1 or 2 years later.
And despite long warranties, the original manufacturers were nowhere to be found. They had run away from their warranty obligations. All the cheap solar offers on the market right now also use cheap inverters. Do not expect the same lifespan and after-sales service from those as you would for the top-of-the-range solutions. You will be purchasing a headache.
The problem with replacing them
If you are to purchase a cheap solar inverter and come across an issue with its performance, often the unit is a write-off. While you wait for a replacement unit to arrive (if one arrives) you’re left with a solar power system that doesn’t deliver any power.
As the customer, you should push to insist that if the solar inverter needs to be repaired off-site, you receive a swap-in unit. This means your solar system is still operational, while your original solar inverter gets fixed. This is something you should go over before committing to an off-site repair of your inverter. If you wait for the professional to come out to collect your inverter and then ask for a swap-in, and they do not have one there and then, you may come unstuck and could wait for months to get your repaired unit back. So keep it simple and do not buy a cheap solar inverter.
Microinverters and optimisers sit on roofs under the panel and are engineered to endure hot climates. In fact, high-quality manufacturers like Enphase and Solaredge have tested their microinverters and optimisers in Australia for many years in real-life installations, and they have operated trouble-free on hot roofs for a decade plus.
To reflect this, in Australia Enphase have put a 10-year warranty on their microinverters installed since April 20, 2020. For optimisers, SolarEdge provides a product warranty of 25 years on their power optimisers in Australia.
What causes an inverter to stop working?
No solar inverter is immortal. There is a whole range of reasons an inverter, microinverter or optimiser solution will stop operating. Here are the top reasons, and again a cheap inverter is much more likely to die an early death for one of these reasons.
Water enters the electronics
Most installers place solar inverters outside, and typically, these devices come with an IP54 rating or higher, indicating their weatherproof nature. However, electronics and moisture form a bad combination. When water enters the inverter, it can cause short circuits or corrosion. This infiltration can result from damaged seals, direct water exposure, cracks in the housing, or placement in areas vulnerable to floods or heavy water flow, like from an overflowing gutter.
Overheating damages components
Solar inverters inherently produce significant heat. If continuously exposed to sunlight and lacking proper ventilation, an inverter can overheat. This overheating reduces efficiency and can lead to early failure. Some main causes include objects obstructing the solar inverter’s ventilation slots, preventing adequate airflow; relentless exposure to direct midday sunlight, when the inverter works hardest, or elevated ambient temperatures, such as those reflected from nearby walls or surfaces.
All electronic components, from capacitors and resistors to transformers, experience wear over time. Therefore as with all electronic devices, there’s a natural end to a solar inverter’s lifecycle where components degrade and become less efficient. Constant exposure to the elements over the years will inevitably wear down some components, even if they were top-notch at the outset.
Early component failures can arise from the use of cheaper subpar components or even voltage spikes and lightning strikes.
Contemporary inverters boast advanced software to enhance efficiency. However, like all software, it’s not immune to bugs. Such glitches can lead to firmware issues due to incompatibilities, failure of software updates or outdated software versions causing issues. Nowadays with more and more batteries and battery management systems, inverter software issues can also lead to the battery charging not working. Again cheap batteries and hybrid inverters have this issue much more than quality gear.
Occasionally, a product can have inherent issues from the manufacturing process, and quality control is not the same for every manufacturer. In the past some cheap solar inverters when one ordered 100, actually 105 arrived, to make up for the models that we likely to be already dead on arrival. In this instance, many defects slipped through, because the quality control processes were not stringent.
Corrosion and environmental factors
Salt exposure is not a friend of inverter solutions. Especially in coastal areas, the salt in the air can enter the equipment and lead to corrosion, affecting the inverter’s overall lifespan. Proximity to industrial areas or regions with high chemical pollutants can also have a corrosive effect on the solar inverter’s interior components.
Dust and debris accumulation due to a lack of maintenance
Heavy dust can clog up the inverter’s ventilation systems, leading to overheating issues. Also over time, debris such as autumn leaves might cause physical blockages, hampering the inverter’s performance.
Solar inverters are like a stable grid. Inconsistent voltage from the grid over a period can cause the inverter to malfunction. For example, pushing the inverter to handle more power than its capacity can result in system failures. Into the same group fall unexpected power surges: Sudden increases in power demand especially if frequent can strain and damage the inverter.
As you can see there are many factors to take into consideration when looking at how long a solar inverter can last. Sometimes it is as simple as poor install practice. Unfortunately, cheap solar inverters are much more likely to break down based on one of the factors outlined above, than quality gear.
While designed for long-term use, quality solar inverters, optimisers, and microinverters are not exempt from environmental and operational challenges. By ensuring proper installation, regular maintenance, and timely software updates, the life and efficiency of these crucial solar components can be maximised.
What is the main failure reason?
The main reason why an inverter would stop working is that they have been operating for a prolonged period of time under hot conditions. If you want to decrease the likelihood of this occurring you should have your solar inverter installed in your garage or the most southern-facing wall of your house. Installing your inverter in these places can help you get an additional 3 to 5 years of high performance, compared to an inverter that is sitting outside in the heat on a northern or western wall.
In such instances, the key parts of the solar inverter that do stop working are the electronic compartments. If damage occurs to one of these components close to the motherboard, the repair costs can be high. Often, it’s not economically viable to fix it, especially since inverter technology and integration improve every few years.