How do I know if my solar panels are working?

Fast read

This is a crucial check-up to ensure you reap your solar monetary and environmental benefits. So it is essential to check the inverter monitoring data.

Relying on your electricity bill to determine if there is a problem with your solar panels is not recommended, as bills are usually monthly or quarterly and can change with the seasons, making it hard to tell if your system is underperforming. Of course, if the system has been dead for months, a high bill will be able to tell you that.

Please look at the inverter to check if your system is performing correctly. Inverters usually have a simple red or green light system to indicate the system's state.

A green light indicates that the system is functioning correctly. However, a red light during daylight hours means a fault in the system. You should also check the inverter data display system and consider using an online monitor option if your inverter brand offers it.

How do you know if your solar panel system is working well?

You can only reap solar’s monetary and environmental benefits if your system functions correctly. Therefore it is essential to familiarise yourself with the steps to ensure your solar panel system is working correctly.

Can’t I use my electricity bill for a solar performance check?

You mustn’t rely on your electricity bill to tell you if there is a problem with your solar panels.

Firstly, electricity bills are usually monthly or quarterly; this is a long time for an underperforming system to run. At this time, you could instead seek to amend your system’s issues. For example, if the solar panels fail to work, the problem should be addressed and known ASAP, rather than waiting for an expensive bill to come in and then solving the issue.

Quarterly bills, in particular, are an unreliable measurement gauge because, usually every three months, the household’s usage patterns change with the seasons. With varying energy bills comes constantly changing information about your solar system’s performance, making it hard to tell if your system is operating but underperforming.

Moreover, bills are not the best form of performance measurement because they don’t explicitly provide data about the actual performance. Instead, they measure the electricity supplied and exported to the grid.

Women calculating her bills
Checking if your solar panel system works properly can involve some calculations

Are you checking the inverter to see if your solar panels are working appropriately?

Inverters usually have a simple red or green light colouring system to indicate the solar panel’s state. A green light indicates that the system is functioning correctly. However, a red light during daylight hours means that there is a fault in the system – that it is not working correctly.

You should check the display screen on the inverter for an error code if you see a red or flashing orange light. An error code will indicate technical problems with the inverter/system, and you should contact your installer if you see one.

Would you happen to know how to check your inverter’s data display?

To check your solar power system’s performance and ensure it performs to its rated output, you should check the inverter data display system. The inverter display should provide data such as the total kWh produced since the system’s installation, the amount of kWh produced during that day, week, or month, and the amount of kWh supplied to the house/electricity grid over a specific period.

Online inverter monitor accounts and apps associated with your system are another way to check the performance. If this is available to you, your solar installer would have told you, and it is associated with newer models of solar inverters. These online companion websites provide graphs and detailed data that you can use to monitor your solar panel system’s performance at its rated output.

Getting Solar Analytics is another option. This monitor platform uses AI and algorithms, including weather data, to predict what your solar PV system should be generating and what is achieved. If your system constantly works poorly, it will send an alert to the installer and the owner – recommending a proper inspection.

installer inspecting inverter to see if solar system is working
Getting more information on your energy usage can be as simple as checking your inverter

Understanding the derate factor will help determine if your solar panels are working

Consider the solar panel derate factor when considering whether your solar panel system works correctly. This is the factor in which solar panel performance deteriorates each year. On average solar panels lose efficiency each year by about 0.5% to 0.7%. So after ten years, you should not be surprised if your solar system produces 5 to 7% less electricity each year than in its 1st year.

Factors such as dirty solar panels, soiling, shading, and varying weather conditions work together with the solar panel’s deterioration over time to reduce the energy output. While quality solar panel systems mitigate these factors, keep them in mind when looking into why your solar system is not producing its rated power output.

Sometimes a simple solar panel clean after a prolonged dry period can improve performance by up to 5%.

How many kWh should your system produce over one year?

In any given year, the solar panels on your home should work within 90% of the outputs listed below. We also offer an output calculator to check your specific postcode.

How many kWh per day should my system produce for 1 kW of solar panels each year? So for a 5kW system, for example, please multiply the numbers below by five.

Adelaide4.2 kWh Alice Springs5.0 kWhBrisbane4.2 kWhCairns4.2 kWhCanberra4.3 kWhDarwin4.4 kWhHobart3.5 kWhMelbourne3.6 kWhPerth4.4 kWhSydney3.9 kWh

12-month monitor data

For those who have had their solar system for more than 12 months, a suitable inverter can tell you your daily production over the prior 12 months. If you suspect your solar panels are not working correctly and underperforming but can not work out why. A call to a quality-focused solar company might be the only option to resolve the issue.

Notify of
1 Comment
Newest Most Voted
Inline Feedbacks
View all comments

Find your local installer