Researchers from University of New South Wales have found that a fifth of solar panels fail much faster than expected, uncovering a critical challenge in solar energy.
Researchers found that some solar panels may only last for only half their expected lifetime.
The reason behind the so-called long-tail of such failures could be attributed to tiny hairline cracks and other minor manufacturing flaws missed during quality control.
The research paper could help raise the standard of solar panels and make solar farms more cost effective and reliable.
Yang Tang, one of the authors of a paper on the subject published in IEEE, said: “For the entire dataset, we observed that system performance typically declines by around 0.9% per year. However, our findings show extreme degradation rates in some of the systems.
“At least one in five systems degrade at least 1.5 times faster than this typical rate, and roughly one in 12 degrade twice as fast.
“This means that for some systems, their useful life could be closer to just 11 years. Or, in other words, they could lose about 45 per cent of their output by the 25-year mark.”
The UNSW team analysed annual production data from tens of thousands of photovoltaic systems produced globally.
The team found that there are samples that fail a lot more rapidly than should be expected.
This long tail of failures poses a large financial risk for solar farms, where hundreds of thousands of panels are installed.
The study found three major reasons for panels to fail.
The first is interconnected failures, where the issues don’t just add up but instead multiply.
The second reason is rapid failure when modules are relatively new. These panels likely have critical manufacturing defects or material flaws.
Finally, there are minor flaws that result in a sudden severe performance loss at a random point.
Dr Shukla Poddar a co-author of the paper, said the team is hoping the research will help solar panel manufacturers and those building large solar arrays.
“We would like to get even more data from large-scale solar farms to analyse real-world failure rates in even more detail, so we can then make recommendations to the manufacturers of these modules.
“Secondly, we aim to understand different factors contributing to module failures in different climate types to develop early detection system and recommend manufacturers to improve design robustness.
“Thirdly, testing authorities should be informed of real-world degradation patterns across diverse climates and consider combining stress tests to better replicate outdoor operating conditions.”
