Solar panels from reputable manufacturers typically have a lifespan of 25 years, backed by performance and product warranties.
In places like Australia, with our harsh sun, humidity and salty air close to the coast, low-quality panels can face issues in just 2-5 years. Problems with cheap panel failures can be plentiful include delamination, which allows water to corrode the cells, and PID, affecting the panel's efficiency.
Additionally, microcracks can lead to hotspots, decreasing efficiency and possibly cracking the panel. Other issues encompass snail trails, junction box problems, and faulty fake plugs. It's crucial to invest in quality panels from trusted brands for longevity.
How long do solar panels last in Australia and why could they fail?
When making an investment like purchasing a solar PV system, you want a beneficial return. We should all know by now what solar panels do and the benefits they offer, but how long do they last? If you have to replace them every couple of years, you would not actually be making money. Unfortunately, this is exactly what happens with cheap solar. So, how long do solar panels last in Australia and what can damage solar panels?
Many solar panel manufacturers claim that their panels will last 15 to 25 years. This is subsequently supported by the performance and product warranty of 25 years that many of these brands put on their panels.
The performance warranty covers the output of the solar panels, while the product warranty covers the physical item and any damage that may occur to it. Specifically, the product warranty has crept up from 10 years to 12, then 15, and now 25 in recent years. In fact, there is one manufacturer that offers a 40-year product warranty! However, while a 40-year warranty sounds great at first, will panels with today’s technology still be relevant in 40 years?
In any case, the length of the product warranty can be a good indication of how long the solar panel manufacturers expect their panels to last.
How long should solar panels last in Australia?
As a customer today, you should expect a quality solar panel from a good manufacturer to last 25 years. Cheap panels have been known to suffer from a range of issues and can go to the tip or recycling for as little as 3 to 5 years. Unfortunately, even if they have long product warranties, this is no help to the consumer, because inevitably such manufacturers disappear and close their Australian operations.
The key here is to get panels from an established and GOOD panel manufacturer. One of the problems in Australia today is the amount of cheap and therefore low-quality solar panels used. These cheap panels can last only a few years and the issues they fail are explained below.
Delamination is the process where the two plastic sheets on the front and back of the panel peel apart. This is a more prevalent issue in Australia than in other places as the hot and humid climate here makes this failure more likely. Cheap panels save electricity in manufacturing and the lamination process time is reduced, leading to issues years down the track.
Once the sheets have opened up, even just a little water can get into the panel and react with the busbars and cells. When water gets into the panel, corrosion occurs. This will initially not only limit the efficiency of the technology but in time make the entire solar panel inoperable by completely stopping the ability of the panel to convert sunlight into electricity. In this circumstance, replacing the solar panel is the only solution. Panels with water ingress can not be repaired.
2. Discoloured backing sheet
Usually, the backing sheet of a solar panel is completely white. However, in some cheap low-quality panel batches it is possible to see discoloured backing sheets turning yellow and brown. Over time such sheets not only make the panels look ugly, but further cracking can occur. So what causes the discolouration?
Whether or not the backing sheet will become discoloured begins with the quality of the backing sheet material initially used. If the manufacturer uses high-quality material, with UV stabilisation the likelihood of discolouration is minimal. However, if the manufacturer is to use low-quality material, which will look the same initially, the Australian Sun is likely to punish the panel with discolouration of the backing sheet.
The backing sheet can also subsequently become very brittle. This begins the previously mentioned issue of delamination, where water can then get into the cells of the panels and cause corrosion, killing the panel’s operations.
Hotspots are a lot more likely to occur with low-quality solar panels as these can commonly come riddled with microcracks.
Microcracks are when cells in the panels have small unnoticeable cracks in them, causing resistance to the electron flows. When this first occurs, there will be a localised area of the panel that has a severe decrease in efficiency, ultimately limiting the output of the entire solar panel. This resistance will further develop and then become a hotspot. If this hotspot gets hot enough, the backing sheet will show burn marks and the glass of the panel can crack, and replacing the panel will be necessary.
As panels nowadays in Australia will need to have fire retardant in solar modules, the likelihood of hot spots causing a panel fire is very low.
4. Water ingress
As the name suggests, water ingress is when water penetrates the solar panel, usually due to compromised seals or gaps in the panel’s casing, or delamination. The presence of water can damage the internal components, leading to reduced efficiency and inevitably a complete failure.
5. Burn marks
Solar panels may develop burn marks if there’s a failure in the junction box such as a bypass diode failure or failure at the soldering points of the panel. These burn marks are often a result of hot spots that have gone unnoticed and can render the panel ineffective.
6. Broken glass
Any cracks or broken glass covering a solar panel isn’t just an aesthetic problem. It will always lead to panel failure because dirt and moisture can now easily penetrate, attach the lamination and then enter the panel and cause corrosion and degrade the cells.
7. Bypass diode failure
A bypass diode is designed to protect the solar cells from overheating when they’re shaded. If this diode fails, sometimes via too much strong shade for prolonged periods, the shaded cells won’t get protected, leading to overheating and hot spot damage.
8. Degradation beyond predicted rates affects how long solar panels last in Australia
Solar panels naturally degrade over time. However, the heat and humidity in Australia can speed this process up. If a panel degrades faster than its predicted rate (typically 0.3- 0.7% per year), it might be a sign of manufacturing faults and defects.
9. Snail trails
Snail trails are patterns that look like trails left by snails. They are a sign of a chemical reaction between the encapsulant and the silver in the solar cells. While these trails don’t immediately reduce the panel’s performance, they may lead to more severe issues, as they can be a sign of micro cracks and lead to other issues over time.
10. Potential Induced Degradation (PID)
PID occurs due to stray currents that can degrade the solar panel’s performance. It’s primarily caused by voltage, heat, and humidity, which lead to performance degradation over time. While this was a big issue a decade ago, modern-quality panels do not display this issue very often.
Microcracks can form during the panel’s manufacturing, transportation, or installation. These tiny cracks might not immediately affect performance but can grow over time and reduce the panel’s efficiency, causing resistance to electron flow, which over time can then develop into hot spots and cracked panel glass. For this reason, even a quality panel can be stuffed up by a rough install crew.
Corrosion is common in areas with high humidity or salt-rich air environments, near the coast. The aluminium parts of the solar panel or the racking frame and clamps (especially if cheap un-anodised racking was used) can corrode, leading to reduced structural integrity and potential performance issues with the panel.
13. Poor quality materials or manufacturing methods
Poor quality materials or substandard manufacturing processes can significantly reduce how long solar panels last in Australia. It’s essential to invest in panels from reputable manufacturers who adhere to quality standards.
14. Physical damage
Panels can be damaged via physical impact. This can be hail, falling objects, or other external impacts, which can compromise the integrity of the solar panel. Such damage not only affects the current performance but may also introduce vulnerabilities and cracks that reduce the panel’s overall lifespan.
15. Poor installation
Even the best solar equipment can suffer if installed by unqualified staff. Poor installation practice can lead to numerous issues, from microcracks caused during installation to inadequate angling that reduces exposure to sunlight or increases shadowing on the panels. You need qualified electricians to perform this task, not overseas students after a quick buck.
Other issues that affect how long solar panels last in Australia
While the previously mentioned issues are the most common, there are some other issues that can occur with low-quality solar panels. These include fake MC4 plugs burning out under load or flimsy panel frames and racking failing in heavy winds.
The lesson here is that if you want a long-lasting solar panel, buy from an established brand with a trusted backup service in Australia. Buy the system from experienced local installers who will not recommend cheap material because they do not want to get involved with additional warranty work. Remember that cheap solar panels, which are used in cheap solar offers have seen failure rates close to 100% after a short period of time.
A last thought about how long solar panels last in Australia
Quality solar panels are built to last a long time. On average, a solar panel’s lifespan is about 25 years. However, this doesn’t mean they stop producing electricity after this period. Instead, their efficiency gradually decreases. After 25 years, a panel might operate at around 85% of its original capacity, given there are no major failures. Then over the following years, it will decrease further in performance till it is not economically viable to keep the panel. Proper maintenance, routine inspections, and addressing minor issues promptly can help ensure your solar panels live a long and productive life.