Subpar solar: How to spot and improve a faulty system

When John Kritikos made the decision to install solar panels on the roof of his Sydney home two years ago, bringing down his family of five's electricity costs was high on his wish list.

"It was always in the back of my mind, but during COVID with five people at home our electricity prices were rising quite significantly, so the way that I looked at it was that solar was just a good investment - it was going to save us money and it's good for the environment.

Kritikos says that the decision was quickly vindicated when the family's first electricity bill came in at just under $100 after a full quarter of solar. However, as time passed he had a sneaking suspicion that the panels should have been saving the family even more money - and he was right.

After reaching out to solar and energy monitoring provider Solar Analytics, Kritikos discovered that the electricity plan he was on wasn't actually optimal for his system, but since making the switch to a new plan he's seen a big difference in his bills.

"The switching over process was easy and I was even more pleased when I got my first bill and found out that I was in credit for $30 for the first month. And on my last statement I was $180 in credit."

The Kritikos family are my no means alone either. New data compiled by Solar Analytics has found that as many as two thirds of households with rooftop solar aren't saving as much as they could be because of faulty systems and poorly-matched electricity plans.

How can you tell if your system isn't working properly?

According to Stefan Jarnason, the chief executive of Solar Analytics, a reasonably-priced solar system from a good retailer should last about 25 year and very rarely break down. But like any system, things can sometimes go pear-shaped though.

Jarnason says that there are plenty of ways for a system to stop working to its full capacity, including everything from a panel being hit by a falling tree branch, to something going wrong with the inverter and even a mistake from a technician.

"We saw one recently where a solar retailer went out to do a clean and inspection, and all was good, but when he left he accidentally left one of the DC isolators on the roof in the off position. That meant half of the solar system was switched off. Of course, the customer could never have noticed this because the system was still generating power, but our software picked that up straight away."

The good news, says Jarnason, is that faults impacting the whole system should be relatively simple to spot, though not necessarily right away - it might take a month or two until your energy statement comes in before you're able to see that you're not exporting electricity and have a higher bill.

"What is difficult is the more subtle things," says Jarnason. "For example, picking up when half of your system is not working is much more difficult."

"You've got two ways you can pick these up. You can use a company like Solar Analytics and we'll do it for you, or you can do it the 'retired engineers way' which involves using an Excel spreadsheet to compare weather and monthly bills and all that. There are plenty of people who do that and it works perfectly well for them."

While the impact a faulty system can have will differ from home to home, Jarnason notes that it's important to identify and remedy and issue as soon as possible.

"It totally depends on the household, but if your system is off you're no longer going to be saving that 70% off your electricity bill. And if your system's working at half its capacity, you're going to be paying an extra 30% on your energy bill."

Nailing down the right electricity plan

Another factor potentially leaving some solar users, like John Kritikos, worse off than they need to be is ill-fitting electricity plans. Part of the issue, explains Jarnason, is that comparing electricity plans isn't the easiest task for solar customers.

"Australia has a competitive electricity retail market which is excellent. The thing is, comparing electricity plans becomes very complex if you have solar, because you may be looking at plans and wondering whether you should get a time-of-use tariff, a flat tariff, a high feed-in tariff or a low feed-in tariff with a lower consumption tariff."

Once again, there are different ways for households with solar to seek out a plan and provider to suit their needs. There are plenty of resources online for solar users to compare energy plans and tariffs themselves, or there are paid alternatives like Solar Analytics which can help with the process.

Either way, Jarnason says that there's not only scope for many households to save more on their energy bills, but to reassess their existing plans more regularly.

"We've found that three in four customers who start with us could be on a better plan and save at least $100 a year and, on average, over $400 a year.

"What's interesting is that when you switch your plan once, in a year or 18 months' time it's almost never still the best plan. Your energy usage may have changed, you might have installed more solar or a battery, a better plan may have come on the market or your current plan may have sneakily increased."

Do solar panels need maintenance?

While Jarnason says that solar panels of a reasonable quality should last 30 years, they might need some maintenance along the way. Although he also notes that it is electrical equipment, so solar owners should be cautious and enlist the help of an expert for servicing.

"Every five years - and I think the Clean Energy Council recommends every two years - it's worth having your solar retailer come out and give the solar system a once over and a service to check all the wiring, and check for things like leaf build up and degradation of cables.

"In terms of cleaning, I've had solar panels on my roof now for 12 years and I haven't had to clean them once. Having said that, I know friends who have had an antenna or something where birds sit on and make a mess, and they have to go up at least once a year and just clean off that patch, otherwise it will damage the panels. In general, the rain cleans them perfectly adequately though."

Solar Victoria suggests that cleaning panels of dirt and debris can be as simple as giving them a rinse down with a garden hose or brushing them with a long broom. But like Jarnason, they recommend seeking the services of an expert for professional cleaning and servicing.

If you're interested in learning more about installing solar check out our article on affordable renovations for energy efficient homes, or if you've already been onboard the solar train for years then it may be worth considering if it could be time to upgrade your solar panels.

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