Many models of solar panel come with a 25-year warranty, which may lead you to believe that they’ll “live” for 25 years. The reality is you’re your solar panels’ lifespan could be much longer, sometimes up to 50 years.
However, the efficiency of your solar panels will fall over time, so those vintage 1970s solar panels aren’t going to be kicking out much juice by now. Modern panels degrade over time, with their output falling by 0.3-1.0% each year. The better the panel, the slower this rate of decline, with top-notch panels such as LG losing just 10% of their performance after 25 years.
What your solar panel warranty means
That 25-year warranty rests partly on the fact that your panels should lose a set maximum of their performance by the end of the period. In the case of LG, their output should have fallen by no more than 10%, for example. It’s hard to quantify and enforce, but this promise gives you a good idea about the quality and rate of degradation.
Solar panel degradation
While high-end panels lose 0.3% or so of their efficiency each year, cheaper panels can lose up to 1% each year. By the end of 25 years, cheaper panels could be operating at 75-80% of their original capacity.
How long should your entire system last?
While it’s reassuring to know that your panels will still be working fine (ish) after 25 years, the rest of the system will probably need some attention long before this. There are a few factors that’ll affect the longevity of your solar power system as a whole.
A common issue with systems is the inverter. A good-quality inverter should last for 10 years or so, but cheaper ones often fail earlier.
The quality of your solar panels
Cheaper panels sometimes don’t live up to their promises. Even if they do, they might not be able to maintain this output for anywhere near as long as the manufacturer claims. Inferior panels are more prone to technical faults, such as hotspots, which will eventually cause a failure in that panel. Furthermore, attractively-cheap-but-obscure manufacturers might not be around when your panels start to fail four or five years down the line, so that 12-year warranty won’t be honoured.
The installer you choose
Again, you get what you pay for. If your installation company isn’t as committed to training and excellence as it should be, then you might run into issues after a few years, including entire system failures and even safety issues.
Look for approved solar modules
To help you to make sure you’re choosing the best panels possible, opt for models that are approved by the Clean Energy Council. The CEC approves solar modules for supply and installation within Australia. You’re doing yourself two favours here, because non-approved modules don’t qualify for any state or federal rebates.
How to improve the longevity of your solar system
Use a smart monitor
Monitoring the output and performance of your panels is important as this can pick up any minor issues before they grow. Your installer can, if you don’t use a monitor, measure and assess the performance of your array.
Keep your solar panels clean
Keeping your panels clean makes sure that they’re working to the best of their potential. If any debris accumulates in a particular area, then it can lead to hotspots and corrosion, so it’s important to have an annual clean-up and inspection.