How long should a solar power system last?

It’s a long-term investment with a long-term pay-off for your hip pocket and the environment.

But putting solar panels on your roof isn’t the end of the story. How do you get the most out of your system, and what happens if it fails?

How long should the solar panels and inverters last?

Hunter-based Trade Pro Solar’s Tim Brown said good quality solar panels — such as LG, Sunpower, or Yingli Energy — would last 25 years.

Quality mattered for inverters, too,  and reliable brands had a 10-year standard manufacturers’ warranty on their inverters, he said.

“A lot of the cheaper inverters don’t have the lifespan in hot Australian conditions,” he said. “They will potentially fail on hot days.”

Mr Brown said he was frequently called on to repair older systems with poor quality parts, and generally replaced “like-for-like” – but adding panels to the existing system installed before 2011 would require it to be upgraded to meet 2018 regulations.

Depending on the components used it was sometimes better to leave it and install a completely new system, he said, but the older good-quality ones were worth keeping and maintaining.

LG general manager of solar and energy Markus Lambert agreed inverter solutions usually need to be replaced within a decade.

With the system checked at that point, and a proper maintenance regime carried out, users could get another 10 to 15 years out of a system, he said, explaining that LG panels came with a 25-year product warranty.

Smart Energy Council chief executive John Grimes also pointed to the inverter as the point of failure, saying they had a variable lifespan.

“Never put an inverter in direct sunlight,” he said, adding they could fail around the eight or 10-year mark.

“Don’t be afraid to make a warranty claim, and go for a 10-year warranty on an inverter.”

Keep them maintained

According to Warwick Johnson of Sunwiz Solar Consultants, the key bit of maintenance was getting them physically and electronically checked every year. “Just to make sure they’re safe, essentially.”

Mr Johnson said the panels did self-clean to a certain extent, but might benefit from an additional go-over. The only weather of concern for panels was hail, he said, and they generally had to be hailstones bigger than golf balls.

Mr Grimes said solar energy systems usually did not need a lot of ongoing work.

“In terms of performance, they don’t require much but do keep an eye on the system. If an error comes up, it will shut down,” he said. “Make a point, once a week, to look at your inverter, and make sure there’s not an error message there.”

What should you look for in a supplier?

Mr Grimes said it was important to consider components used in the solar energy system, and who was going to install and maintain it.

“There is variability between brands – not all solar panels are created equal, not all inverters are created equal,” Mr Grimes said.

He suggested consumer look at quality tests, such as those run by Choice, and to opt for panel and converter brands that have been on the market for a while with a reasonable footprint in Australia.

Mr Brown said buyers should look for suppliers that had a track record in Australia and favoured companies with vertically integrated production.

Mr Lambert agreed research was key. In 2014 there were 480 solar manufacturers in the game, he said, compared to 57 now. Similarly, since 2011, 697 companies who installed solar energy systems had left the market. This meant that some owners were left with systems that were considered to be “orphans”.

“The companies that installed them, or made them, don’t exist any more,” Mr Lambert said.

“A lot of people went for the bargain then wondered why it didn’t last very long,” he added. “In many cases, the workmanship is such that it can’t repaired.”

Watch out for warranties

Mr Lambert highlighted a key difference between performance and product warranties for solar panels.

Many cheaper products were advertised with long performance warranties, such as 25 years, but if the panels have failed at year 12, for example, buyers would need to measure the reduction in performance, which required it to still be semi-functional.

“In the 12 years I’ve been in the industry, I have never seen anyone successfully claim on the performance warranty,” Mr Lambert said.

He explained that to prove performance issues, owners would need to have someone qualified to remove the panel from the roof, ship it for testing and then have it returned, something that could cost about $600. “No one is going to do that,” he said.

Mr Johnson said it was  “definitely difficult to claim on a solar panel performance warranty”.

“The equipment needed to prove the claim isn’t readily available.”

Future-proof your purchase

“Don’t buy the solar system for today – look where we are heading for tomorrow to buy a future-proofed system,” Mr Lambert said, citing electric cars as one emerging product that could demand a lot of a household’s power supply.

“In 10 years’ time, if you need a bigger system, you’ll need a bigger roof, or to tear the whole thing off and start again,” he said. “Try to work with products that allow them to have spare roof space for future expansion.

“If you buy something that fails, and the models are always evolving, it’s really hard to get spare parts. They’re not that expensive, but they can be hard to find.

“Buy something that is going to last a long time, so you don’t have to replace it.”

Mr Brown said that it was important to get a solar-friendly energy retailer, and a custom-designed system would result in the best financial outcome.