Everything we buy for our homes has a limited lifespan. Refrigerators, for instance, have an average working life of 15 to 25 years. Air conditioning units tend to last between 12 to 15 years before needing to be replaced. Avocados, on the other hand, seem to be specifically engineered to expire one day before I’m ready to eat one. Just like everything else, a solar energy system has a finite life span in which it will function efficiently. In this article, we’ll look at the individual components of a photovoltaic system, how long those components last, and how solar equipment differs from other types of electricity generation.
A solar system is made up of several components. When compared with other types of electricity generation technologies, PV systems are fairly simple in their configuration. One thing that distinguishes solar from other types of generators is that there are no moving parts. Every variation of fossil fuel technology that produces electricity uses combustion to heat water and create steam to drive a spinning turbine. In this way, heat energy is converted to kinetic energy, which is then converted to electricity. Renewable energy sources like biomass and geothermal operate in a similar manner, minus the combustion of fossil fuels. Wind and hydro don’t rely on any heat energy, just the natural movement of wind and water to drive the turbines.
Photovoltaic solar cells are completely unique from other types of electricity generators because they rely on the Photovoltaic Effect. The PV effect describes a natural phenomenon in which electrons are harvested directly from the sun’s energy, using specialized layers of minerals and semiconductors. We’re not going to delve into the physics here, but if you’d like to read more about the photovoltaic effect you can learn more by following this link. We tend to think of solar panels as being a modern technology, but in reality, the PV effect was first discovered way back in 1839 by a French physicist named Alexander Edmond Baecquerel. One of the many advantages of solar panels is that they don’t have any moving parts (unless the panels are mounted on a tracking system), and so there’s less room for equipment failure compared with other technologies.
Although there are no moving parts, that doesn’t mean that solar panels will last forever. The panels degrade over time, which leads to a slight decrease in production over the life of the system. The National Renewable Energy Laboratory has conducted one of the world’s most comprehensive studies on this subject, titled the Photovoltaic Lifetime Project. Their findings indicate that modern solar cells degrade at a rate of less than 1% per year. Most module manufacturers provide warranties on their equipment ranging from 20 to 30 years, ensuring that the modules will continue to perform at or above the level of degradation for that time period. Unfortunately, there is no data that shows the maximum lifespan of modern solar equipment, since manufacturing processes have aimed to improve the durability of modules made within the last 10 years. Despite the lack of concrete evidence, it’s widely suspected that modern solar cells could continue to produce power for years after the manufacturer warranties expire.
Another crucial component of PV systems are the inverters. The photovoltaic effect produces DC (direct current) electricity, but our electricity grid operates with AC (alternating current) power. The function of the inverter is to convert the solar electricity from DC to AC so that it’s suitable to be used in the home or exported to the grid. The typical expected lifespan of a PV inverter ranges from 8–12 years. There have been isolated cases of solar inverters lasting for up to 20 years, but typically the equipment is expected to fail around the 10-year mark.
The timelines outlined above are based on national averages, but there are several other factors that will play a role in determining the life of your PV system. These factors include weather, average temperature, and frequency of system maintenance. In order to extend the life of your solar system, there are a few things homeowners can do to keep their equipment functioning as well as possible. The first important thing a homeowner must do is to partner with a reputable solar installer, who will be sure to closely follow all manufacturer instructions when installing a system. A loose wire or improper connection can create irregularities in the system, which can greatly impact the overall lifespan. The second piece of advice for homeowners is to keep their systems clean and free of any debris that might damage the equipment. Finally, it’s important to have your system monitored and inspected regularly to ensure that the equipment is performing as expected. Barring any unforeseen circumstances, these simple steps will help ensure that your system is producing the maximum amount of power during the life of your equipment.