This site is secure. 
High-quality solar panels are very durable and last a long time, and a 25-year warranty has become the unwritten standard among the top solar brands. The best panels often last far longer than this.
Manufacturers such as Silfab and Canadian Solar have started offering a 30-year warranty on some product lines. SunPower Maxeon panels have a 40-year warranty, which is the longest in the industry as of August 2023.
When photovoltaic (PV) panels reach the end of their warranty period, they can still generate electricity at reduced capacity past their guaranteed lifespan.
The best solar panels only lose around 1-3% of their generation capacity during the first year, and then 0.25-0.50% per year. They still have around 85-92% of their initial capacity after 25 years of use.
Solar panels last a long time.
Solar panels are also characterized by their simple maintenance needs. Most power generation systems have moving parts that suffer mechanical wear, but this is not the case for solar modules. Their PV cells can generate electricity for decades, as long as their surface is not obstructed by dust or other particles.
Compare My Solar Prices
Get quotes from local installers
1 fast form = 4 low quotes
Save up to £703 per year
Understanding Solar Panel Degradation Over Time
When comparing solar panels, you will notice that manufacturers offer two types of warranties:
- Product warranty: This warranty covers solar panel failure due to material defects, workmanship errors and other manufacturing issues.
- Power performance warranty: Solar panel specifications include a maximum degradation rate you can expect each year. This warranty covers you if they lose performance faster than the specified rate.
The product warranty is a simple concept, but power performance warranties can be confusing at first. The best way to explain them is with a quick example. Assume your solar panels have a 25-year performance warranty, with 3% degradation on the 1st year and then 0.50% per year. Here is a table of the guaranteed performance over time:
| Years of Operation | Guaranteed Performance (% of Initial Capacity) |
| 1 | 97% |
| 5 | 95% |
| 10 | 92.5% |
| 15 | 90% |
| 20 | 87.5% |
| 25 | 85% |
The power performance warranty applies if your solar panels lose performance faster than the specified rate.
- If the solar panels in this example generate 96% of initial output after five years, there is no problem – the manufacturer specifies at least 95% capacity.
- On the other hand, if your solar panels operate at 93% of initial output after five years, you can file a warranty claim.
The following table compares the degradation rates of some leading solar panel brands, and their remaining capacity after 25 years of use:
| Solar Brand | Product Line | Degradation Rate | Performance After 25 Years |
| SunPower | M-Series | 0.25% per year(2% on 1st year) | 92% of initial capacity |
| REC | Alpha Pure-R Series | 0.25% per year(2% on 1st year) | 92% of initial capacity |
| Panasonic | Evervolt HK Black Series | 0.25% per year(2% on 1st year) | 92% of initial capacity |
| Silfab | Elite Series | 0.50% per year(2.9% on 1st year) | 85.1% of initial capacity |
| Q CELLS | Q.PEAK DUO BLK ML10+ Series | 0.50% per year(2% on 1st year) | 86% of initial capacity |
| Canadian Solar | HiHero Series | 0.35% per year(1% on 1st year) | 90.6% of initial capacity |
These solar brands have excellent warranties, but you must meet certain conditions to get full coverage. First of all, your PV panels must be professionally installed according to the manufacturer’s instructions. Some brands only offer their longest warranty if your solar panels are installed by one of their approved contractors.
DIY solar installations are not eligible for warranty coverage in most cases, unless you purchase solar panels that are specifically designed for DIY projects.
Importance of a Roof Assessment Before Going Solar
Ideally, you should use a roofing material with at least the same lifespan as your solar panels. Otherwise, you will be forced to remove the panels for a roof replacement, and this can void their warranty. You may be able to keep the warranty by hiring a qualified solar company for the system removal and reinstallation. However, you can avoid this procedure completely by installing a durable roof before going solar.
Metal roofs and ceramic tile roofs have the longest lifespan. Metal roofs can last over 75 years, and ceramic tile roofs can last over 100 years. Both roofing materials can outlast your solar panels, and you don’t have to worry about removing them for a roof replacement.
Asphalt roofs have a typical lifespan of 12-30 years. If you install solar panels, there are two main scenarios where you may need to remove them for a roof replacement:
- If your roof shingles are of lower quality
- If your asphalt roof is already old
You can avoid issues by using high-quality asphalt shingles with a rated service of 25-30 years, or by switching to a more durable roofing material.
Wooden shake roofs are not a good option for solar panels. In fact, many jurisdictions don’t allow solar panels on wooden roofs due to fire risks. Even if there is no legal restriction, wooden shakes normally last less than 20 years. If you install solar panels, you must eventually remove them for a roof replacement.
You should not install solar panel systems on asbestos roofs, due to the serious health risk involved. Asbestos dust and fibers are extremely harmful when inhaled, and most solar installers will decline any work that involves this type of roof.
Do Solar Panels Need Maintenance?
Since solar panels have no moving parts, their maintenance needs are very simple. The most important requirement is keeping your solar panels clean. Accumulated dust and other particles block some of the sunlight reaching your PV cells, which also means they generate less electricity.
A rule of thumb among solar installers is that PV modules should be cleaned at least twice per year. More frequent cleaning may be needed if your solar system is constantly exposed to sand, construction dust or other types of debris.
- Solar panels should be cleaned with non-abrasive tools such as a soft brush or squeegee, to avoid scratches.
- Chemical cleaning agents should be avoided, since they can damage solar panels.
- Solar panels can be washed with a hose, but never when they are hot – the sudden cooling effect can cause cracking.
Solar panels suffer a small loss of generation capacity each year, but a drastic drop in their electricity output is a warning sign. Most solar inverters have built-in monitoring apps, where you can check the daily kilowatt-hour (kWh) production. Low productivity during cloudy days is normal, but low productivity during sunny weather indicates technical issues. In this case, you should contact the solar system provider for an inspection.
Note that solar panels can also suffer a productivity loss if there is a new object casting a shadow on them. For example, a low kWh output can be caused by growing tree branches or a recently installed Internet antenna.
How Long Do Solar Inverters and Battery Systems Last?
Inverters are necessary in solar power systems. PV cells generate direct current (DC), your home appliances need alternating current (AC), and the solar inverter is the device that performs the DC-to-AC conversion. The typical service life of an inverter depends on its type:
- String inverters: 10-15 years
- Microinverters: 25 years
When using a string inverter, solar panels are connected in series circuits or “strings”, and their combined DC output is supplied to the inverter. Microinverters are smaller devices, designed to be installed directly on each panel. String inverters gather the DC power from all your panels before converting it to AC, while microinverters convert the output of each panel directly. Generally, you can expect a 10-12 warranty when purchasing a string inverter and a 25-year warranty when purchasing microinverters.
Battery storage systems are optional, but they enhance the capabilities of a home solar system. By themselves, solar panels can only provide electricity during daytime. With a home battery, you can use solar energy at any time – even during nighttime and cloudy days. The lifespan of a battery depends on its chemistry:
- Lead acid batteries last for around 500-1000 cycles, equivalent to 1.4-2.7 years with a daily charging cycle.
- The latest lithium-ion batteries can last for more than 4000 cycles, equivalent to around 11 years with a daily charging cycle.
Lithium-ion batteries are preferred for home solar systems, since they have a much longer service life and efficiency. Most solar battery providers offer a 10-year warranty, subject to certain usage conditions. The Tesla Powerwall, LG Chem RESU, Generac PWRcell, Enphase IQ, SunPower SunVault and sonnenCore are among the most popular home batteries.
Solar panels in the UK typically last between 25 to 30 years. However, their performance may decrease slightly over time.
Factors such as climate, maintenance, and the quality of solar panels can impact their lifespan in the UK. Regular maintenance can help extend their life.
Yes, most solar panels in the UK come with warranties that range from 10 to 25 years. Be sure to check the warranty when purchasing.
To maximize the lifespan, keep the panels clean, ensure they are properly installed, and perform routine inspections to catch any issues early.
At the end of their lifespan, solar panels can often be recycled. In the UK, there are recycling programs and options available to dispose of them responsibly.
Remember to use proper schema markup for FAQs on your website to enhance search engine optimization.
The cost of solar panels in the UK can vary based on factors such as the size of the system and the quality of panels. On average, homeowners can expect to invest between £7000 – £9200 for a 4kW solar panel installation. Government incentives and grants may also be available to help offset the cost.
