How long do rooftop solar panels last?

One of the most common questions we hear from property owners looking to reduce their dependency on the national grid by installing solar is “how long do solar panels last?”

Considering the price tag attached to a solar installation it is difficult to make that decision without knowing how long you can expect your rooftop panels to produce ample energy.

The number of solar panels being installed worldwide, and in our own sunny South Africa, has been growing exponentially since the 2000s. With an industry-standard life span of about 25 to 30 years, most residential solar panels are often sold with long-term loans and leases of between 10 to 20 years or more. Keep in mind that expected solar panel life expectancy doesn’t necessarily mean that the panels stop producing electricity after a couple of decades. It just means that their energy production will decrease, from what solar panel manufacturers consider

Degradation rate

As with most technologies, solar panels will naturally produce less energy over time. This reduced power output is called the degradation rate. Average degradation rates would be at a rate of 0.8% per annum, The efficiency of solar panels producing power over 25 years will reduce by 20%. After 25 years, your panels should still be working at about 80% of their original output. Therefore, a new 100watt panel will incur a 20% reduction in its life cycle, resulting in an 80watt output in year 25. It is worth noting that the median degradation rate for solar panels is around 0.5% a year according to the National Renewable Energy Laboratory (NREL).

Maintenance to extend the life of panels

Solar panels have been designed and built to handle, as well as endure harsh and unpredictable weather conditions over prolonged periods. This is why solar panels are so durable and little maintenance is required throughout their life.

PV systems are inherently very low-maintenance. While solar panels should be pretty much self-sufficient after installation, wash the panels every 2 – 3 months when it’s not raining, to remove dust or any other dirt. If you keep your solar panels well maintained, then you can expect to enjoy them for the full length of their estimated lifespan.

It is also important to check the panel output regularly, either via the inverter or on your monitoring system. This means that if the output is at any point less than the expected amount, you will be able to find out why that is quickly and get your panels back to running at optimum levels of efficiency.

Finally, it is incredibly important that you ensure your solar panels are installed correctly in line with the manufacturers’ specifications and maintained by an accredited partner for the longevity of your solar panels. Bright Light is fully-equipped to assist in the installation of solar projects on rooftops, carports, or any other unused space on your property.

We are experienced solar professionals with a proven track record of installing small, medium, and large-scale rooftop and ground-mounted solar projects. We are a registered member of the South African Photovoltaic Industry Association (SAPVIA). We fully customise our solution to fit your space and energy requirements, and our team of experts is always on-hand to attend to any queries or maintenance requirements. Ongoing maintenance of the infrastructure is included in our fully-funded offering to ensure the enhanced lifespan of your solar system.