High quality residential solar panels usually carry a warranty of between 20-25 years for parts and performance but can be expected to last longer than that.
For example, some panels are still in service more than 30 years since they were installed. You can therefore expect solar panels from a reputable manufacturer to at least last the term of their warranty and beyond on average.
This remarkable service life results from the technology used to protect the active solar cells, and the several layers of lamination that also help with the protection.
The absence of moving parts also certainly is a key contributing factor to the solar panel’s longevity.
How often do you have to replace solar panels?
Because of this quality of manufacture, there is often no need to replace solar panels every few years because of failure or poor performance unless you choose to.
For example, you may want to swap them out for a smaller or more efficient type.
There are exceptions to this though, such as some flexible solar panels and solar garden lights.
How long do flexible solar panels last?
Flexible solar panels though touted as durable by several manufacturers may not last as long as the more rigid counterparts. In fact, they tend to carry shorter performance and parts warranty compared to the fixed rigid solar panels.
Some manufacturers offer warranties of only 5 years for performance and 2 years on parts compared to 20-25 years for example.
Some flexible solar panels have been noted to fail when the laminate allows water to enter and damage the solar cells!
Regardless, they do have the benefit of being lightweight and easy to install on curved surfaces such as boats and RVs.
Before buying a particular model, pay attention to the warranty terms and suppliers reputation for honoring their warranty.
Note: Flexible solar panels should be installed on a rigid surface; Avoid scratches on the surface – Do not walk on them otherwise you risk damaging them!
How long solar panels for garden lights last
Solar panels used in garden lights usually do not last as long as their rigid counterparts because of the cheaper materials used in their manufacture.
In some solar garden lights for example, the solar panels may only last for up to 6 years.
Always to take note of the lifespan of solar panels as quoted by the manufacturer the next time you buy garden lights if it matters to you!
Besides quality of manufacture, there are other factors that affect the lifespan of solar panels.
3 Common causes of solar panel failure
# 1. Solar panel degradation
A solar panel’s power production tends to degrade over its life time. This has been confirmed from field tests conducted on several panels over a long period, that showed an average decline in power produced by the panel of 0.8% per year.
This means that a 200W panel can be expected to lose 200* 0.8% = 1.6W per year.
Over a 25 year life, this adds up to about 40W (1.6 x25) – reducing a solar panel’s a peak power output to about 200-40= 160W.
Besides degradation, physical damage is another cause of early solar panel failure
# 2. Physical damage
Solar panels may suffer physical damage during transportation, installation and in some cases from hailstones or lightning. This can easily affects its power production.
A damaged panel may be easily identified from the cracks or any other physical signs of damage.
Fix: A damaged panel will produce less or no power at all. Replace it!
# 3. Parts defects
Another cause of failure of solar panels comes from low quality of parts used in poorly built solar panels – such as from moisture or water leaks that damage the solar cells.
Always buy solar panels from a manufacturer or distributor with a record of honoring their warranty.
Tips to getting your solar panels to last
- Choose solar panels by a reputable manufacturer, backed up with a warranty and who is known to honor their warranty claims
- Install your panels in areas with low risk of physical damage – falling objects – stones as they may damage the panel. Mount the solar panels on rigid surfaces or frames.
- Avoid any actions that may scratch the panel surfaces such as walking on them during maintenance
Regularly inspect your solar panels periodically especially when you notice an unexplained drop in power produced. Replace any damaged panels!