The question of all the people who made an investment buying solar panels is what is the useful life of the solar panels.

What is the lifespan of solar panels?

Solar panels consist of a few moving parts and are very solid in construction. They are made of stainless steel and plexiglass to insulate and protect the solar cells against hail and storms. All this allows the panels to function for decades without any problems. The oldest solar panel in the world is 60 years old and is still operational.

However, what you must recognize is that solar panels lose their efficiency over time . You can find more information about it at the end of the article.

What is the useful life of photovoltaic panels? – this is one of the most common questions we get. And well! This is a very important issue that you should consider before buying solar panels, because if you invest your money in photovoltaic panels, you want them to work for as long as possible, and thus bring in the highest possible income. Therefore, the useful life of the panels is a key issue in determining how much money the solar farm will bring you. Solar panels last for decades and require virtually no maintenance. This is especially true in the case of solar cells of the current generation.

The performance of photovoltaic panels depends on their quality and location in combination with their useful life. These are the two most important factors when looking at the financial aspect.

What is the real lifespan of solar panels?

It is difficult to estimate the lifespan of solar panels as photovoltaics is still a fairly new field of technology. Much depends on the precision of the manufacturing process. If the solar panel has no manufacturing defects and is not damaged by extreme weather conditions, its useful life will be decades, much longer than the product warranty, usually 10-15 years.

Previous generations of solar panels (2000-2010) are believed to have a lifespan of at least 25 years. The duration of the product warranty and the performance warranty are constantly increasing, thus also increasing the expected service life of photovoltaic panels . Therefore, there is reason to believe that good quality Tier 1 panels can last up to 40 years. The working time of photovoltaic panels is one of its greatest advantages.

A recent study on the loss of efficiency of solar panels has been carried out on more than 2,000 solar panels and found that, on average, a solar panel loses 0.5% efficiency per year. Many older models of photovoltaic panels were included in this study. If the same test were performed only on the current generation of solar panels, the performance loss would be much less. It is worth noting that the study calculated the efficiency losses in individual regions of the world.

The smallest losses in the efficiency of photovoltaic cells were recorded in Europe . This is mainly due to the fact that extreme weather conditions in our region are relatively rare, which can have a negative impact on the durability of photovoltaic panels.

Contrary to popular opinion, PV in Poland is working quite well and is worth investing in. Photovoltaic panels in our climate can produce electricity even when our children grow up and have grandchildren.

The real power of solar panels after a few years.

One of the main disadvantages of solar panels is that their efficiency degrades over time, although compared to the current generation of solar panels, these figures are really low. The acceptable loss of panel efficiency after a specified operating time is determined by the performance guarantee .

The greatest efficiency losses occur in the early years. This also applies to good brand solar panels. We will notice the biggest loss of efficiency in the first 5-10 years. After that, the decrease in efficiency will gradually decrease. When a solar panel loses more than 20% of its efficiency, we can even speak of a technical failure.

Solar panels lose their original power and efficiency over time. This natural degradation is absolutely normal. The most important factor behind performance degradation is the intensity of ultraviolet radiation and extreme weather conditions . Fortunately, the intensity of ultraviolet radiation in our region is low and we rarely deal with extreme weather conditions.

Extreme conditions that affect the durability of photovoltaic panels include:

Warm Temperatures – Solar panels lose their effectiveness on hot summer days, but they wear out quickly too! Solar panels in the desert lose on average about 1% of their efficiency per year, which is a very high value. The main reason for this is the high intensity of ultraviolet radiation.
Hail: Photovoltaic energy can withstand normal storms and hail. For example, LG says its solar panels “are designed to withstand hail up to 28mm in diameter .” However, a large enough storm can cause significant damage. Buying the right insurance can solve this problem.
Frozen, Stagnant Water – Solar PV is generally better in winter than you might think. Snow usually falls from solar panels when exposed to sunlight. However, there are some dangers. Under certain specific conditions, the panel can be submerged in icy water which, when expanded, can seriously damage the panel. However, the problem mainly affects the northern countries of Poland, where winters are more severe.

In our region, a good photovoltaic panel should not lose more than 0.5% efficiency per year. In many cases, the decrease is much less.

Performance guarantee (performance guarantee)

Photovoltaics is a great investment that you intend to enjoy for years to come. The economic benefit is closely related to the amount of electricity generated by the facility each year. The less energy you produce, the lower your income will be. As previously stated, the efficiency of photovoltaic panels decreases with their use, but most manufacturers specify in the warranty the maximum decrease in the efficiency of photovoltaic cells.

All photovoltaic panels must have a performance (efficiency) guarantee. Most brands of solar panels offer a 25-year performance guarantee on their solar panels. However, the key value contained in such a guarantee is the value of the panel’s loss of efficiency over time. The lower the performance loss, the better. Most Tier 1 brands guarantee a performance loss of -0.35% to -0.5% per year. This means that, for example, if a solar panel has lost more than 7% of its efficiency after 10 years old , must be replaced by the manufacturer under warranty. In fact, the efficiency losses will be much lower since solar panel manufacturers calculate the margin of loss with the margin and thus protect themselves.

Generally, solar panels should not lose more than 0.4% of their annual efficiency. So after 25 years, its efficiency should be above 80% of maximum power .

There are two types of power warranties: linear and limited . The first type of guarantee involves a linear loss of performance (from one year to the next). The limited warranty generally includes 2 periods, one for 10 years and one for the next 15 years. The linear warranty provides a better and more realistic maximum loss of performance than the second-type warranty. In most cases, the limited warranty will be reduced to 90% of total production for the first 10 years and 80% -85% of total production for the next 15 years.

Most Tier 1 solar panel brands sell their products with a linear warranty .

As mentioned above, PV panels outperform the 25-year warranty period. So when the warranty expires, the panels should continue to function normally. The current generation of solar panels is expected to last between 40 and 50 years. This includes all kinds of high-quality photovoltaic panels. The oldest solar panel is now around 60 years old and is still operational.

Tier 1 Solar Panel Performance Comparison
The name of the manufacturer	25-year guaranteed performance level for select models
SunPower	92.0%
LG	89.6%
Solar watt	87.0% for 30 years
REC group	86.0%
Q Cells	85.0%
Trina Solar	83.0% for 30 years
ZNShine	81.05%
JA Solar	80.0%
Panasonic	80.0%

Can I extend the life of my solar panels?

Solar panels require little maintenance, although there are a few steps you can take to maintain optimal performance and life:

Check your installation regularly – this is the best way to verify that your solar panels are delivering the correct amount of power. The output can be read from the inverter, but there are also logging systems that can be installed on a smartphone to check both history and real-time data. If the power supply is lower than normal, contact the installer or the panel manufacturer.
Check the condition of the wiring: Check the wiring every year for damage and everything is connected correctly between the solar panels, the inverter and the fuse box.
Clean solar cells: Recommended especially in summer and dry periods. Use only professional equipment or hire a suitable company.

Inverter lifespan (inverter)

Photovoltaics produces direct current, so an inverter is needed in the system. An inverter is a device that transforms electricity from photovoltaic panels into electricity that is used to power electrical devices. Converting electricity is hard work. Therefore, the average life of the inverter is much shorter than that of solar panels.

The life expectancy of an investor is approximately 10 years . Although there are many examples of inverters that are still running smoothly after 15 or even 20 years. The main factors influencing its durability are electrical charges, high operating temperatures within the device, and many moving parts.

Microinverters have a longer lifespan due to lower loads and because they make better use of the capacitor.