The efficiency of solar panels is greater than ever, but the amount of electricity the panels can generate continues to decline gradually over time. All solar panels slowly degrade over time, which means they produce less electricity with the same amount of sunlight. How and why does this happen? Various external factors (such as weather) wear down panels and negatively impact their ability to produce electricity. Do solar panels lose efficiency over time? The answer is yes, but the process is slow and, in the vast majority of cases, the effect is small, easy to calculate and will not affect the homeowner's decision to install a system.
The Department of Energy estimates that for roof systems using current multi-crystalline silicon photovoltaic modules, the estimated payback time in energy savings is only four years. Beyond that point, rooftop solar systems can still produce energy at levels close to peaks for years. Today's solar panels are more efficient and resilient than ever, so it's a good time to invest in solar energy for your home. Technically, there is no expiration date on solar panels.
However, over time, they naturally tend to be less efficient in energy production. Degradation is a critical factor in determining how long you can expect your solar panels to last. NREL data shows that solar panels have a degradation rate of approximately 0.5% per year. Thus, after 20 years of use, a solar panel would be able to produce approximately 90% of the electricity it produced when it was new.
As with most technologies, solar panels naturally produce less energy over time. This reduced power output is called the degradation rate. The average solar panel degradation rate is approximately 0.5%, which simply means that the energy production of a solar panel will decline at a rate of 0.5% per annum. 5 After 20 years, your panels should continue to operate at approximately 90% of their original production.
While solar panels lose some percentages immediately due to LID, the degradation rate slows down significantly for the rest of their useful life. Known as Light-Induced Degradation (LID), this occurs when the boron coating of solar panels oxidizes and partially clouds the panels. There are a variety of factors that can contribute to the productivity of a solar panel and increase or decrease its useful life. Normally, the solar inverter will need to be replaced for the life of your solar system because it is working so hard as the tool that converts DC electricity to AC electricity for your home to use.
Despite being a fantastic long-term investment for many businesses, farms and homes, solar panels are no different in this regard. In fact, from October to March there was a greater percentage drop in solar panel production than in summer. The best thing you can do to ensure the longevity of your solar system is to find a reputable solar installer. There are two other ways in which solar panels can lose efficiency, thanks in part to their chemistry acting against them.
NREL research has shown that solar panels have an average degradation rate of around 0.5% per year, but the rate could be higher in warmer climates and for roof systems. That said, all solar panels are tested under standard test conditions to produce an accurate and standardized efficiency quote. You can count on most photovoltaic solar panels to last 25 years before they start to degrade noticeably. This is mainly because solar panels have no moving parts; they rarely break from the inside and are usually only damaged by external forces, such as poor shelf configuration or inclement weather.
Solar panel systems will continue to produce electricity even after the 25-year warranty period if they are well maintained. However, a solar panel will not die after 25-30 years, but its production will drop significantly below what the manufacturer projected. .
