How long do solar panels last?

Investing in solar panels is an excellent way of reducing your carbon footprint and your electricity bills. It can typically take 10-15 years to see a return on your investment, but how long do solar panels last?

As with all technologies, over time, solar panels degrade, so before you switch to this renewable energy source, it’s good to know how you can maximise their use and your money. Here, we explore how long solar panels last and what you can do to extend your solar panel’s lifespan.

But first, let’s take a quick look at how a solar power system actually works. 

How do solar panels work?

Regardless of the type of solar panels you have, they all work in the same way, as simplified below:

1. Sunlight hits the solar panels
2. Photons of light are transferred into the panels
3. The light frees the electrons that sit in the panels from their atomic bonds
4. The solar cells then collect these electrons to generate an electrical current
5. This electricity is collected in direct current (DC) form before being converted into alternating current (AC) by an inverter

What factors affect how long solar panels last?

There are several factors that can influence how long solar panels last. These include: 

1. The quality of the materials used

The old saying of ‘if you buy cheap, you buy twice’, applies to solar panels. If you buy high-quality solar panels made with durable materials and components, they will be much more likely to last longer than their cheaper equivalents. That’s why, before you commit to buying a solar panel system, you should do your research on solar panel manufacturers. 

2. How well the panels are maintained

Ensuring your solar panels are kept clean and well-maintained will help to prolong their life. A fully qualified technician should inspect the panels annually, and you should keep the panels clear of debris and dirt to prevent damage and optimise performance.  

3. Quality of the solar installation

Poor installation practices can have a negative impact on solar panel efficiency and how long they last. Proper solar installation by trained solar panel installers will help mitigate the risk of problems like structural issues, water leaks, and more. 

4. The rate of degradation

Over time, solar panels will decrease in effectiveness; this is known as panel degradation. On average, solar panels degrade at a rate of between 0.5 and 1.0% every year. So, a typical solar panel’s performance will drop off by around 12-15% over its 25-30 year lifespan.  

5. Environmental factors

Solar panel life expectancy will be affected by weathering, particularly extreme weather like heat waves and heavy snow or hail. While this is unavoidable, exposure to harsh weather will affect how long solar panels last. 

How to extend the lifespan of your solar panel system

To ensure a good return on your investment, adhere to solar panel warranties, and extend the lifespan of your home solar panel system, you should aim to keep on top of the following things.

Clean your solar panels regularly 

Keeping your solar panels clean and free of debris, like bird droppings, will help to improve their performance and help your solar panels last longer. When it comes to cleaning your solar panels, always follow the manufacturer’s advice to avoid damaging the panels. 

Organise inspections with a professional solar panel installer 

Having your solar system inspected by a trained professional enables them to spot any issues, like loose wiring or corrosion. As well as spotting issues, an inspection ensures peace of mind about the overall condition of your solar panels. 

Monitor performance

Tracking the performance of your solar panels will help you keep an eye on the degradation rate of your system, and if there’s a significant drop, it could indicate that there’s an issue. 

Like with boilers and other household appliances, a large number of issues can be repaired relatively easily, provided they're addressed promptly and not allowed to escalate. If you're concerned about the performance of your home's boiler, hybrid heat pump or solar panel system, it's always best to contact a qualified engineer to investigate as soon as possible.

Manage shading and obstructions

Where you can, you should take steps to ensure that buildings and trees do not cast a shadow over your solar panels. Shading can reduce the panels’ efficiency, so keep an eye on any trees or shrubs and ensure they’re pruned and trimmed regularly. 

Adhere to the manufacturer’s guidelines 

When you have your solar panels installed, you’ll receive various pieces of information, including instructions from the manufacturer. Following the recommendations in these guidelines can maximise the lifespan of your solar panels and preserve the warranty of your panel system. 

Implement control measures to manage weather

Extreme weather events, while rare, can impact your solar panels’ expected lifespan and ability to produce electricity. In the UK, we rarely experience tornados, but protecting your solar panels against snowfall and hailstones by investing in weather guards can extend their lifespan.

The lifespan of different solar panel types

The three main types of solar panels used on residential and commercial properties in the UK are monocrystalline, polycrystalline and thin-film panels. Each of these solar panels is made in different ways and will, as a result, have varying lifespans.

Check out our blog for more information on the different types of solar panels, solar panel efficiency levels and the price of solar panels in the UK.

Monocrystalline solar panels

Monocrystalline solar panels are made from a single silicon crystal. While the manufacturing process is complex and the panels more expensive, they do offer high levels of efficiency and can last up to 40 years. 

Polycrystalline solar panels

Polycrystalline solar panels are made up of multiple crystals of silicon in a photovoltaic cell. Often incorporating fragments of silicon leftover from producing monocrystalline solar panels, polycrystalline solar panels are a cheaper alternative that can last up to 35 years. 

Thin-film solar panels

Made from other materials, like copper indium gallium selenide (CIGS) or cadmium telluride, thin-film solar cells are around 350 times slimmer than crystalline silicon solar cells. While their thinner, lighter composition makes thin-film solar cells much easier to install, they do degrade at a faster rate, with a typical lifespan of between 10 and 20 years.

Key takeaways

The lifespan of your solar panels will vary depending on a number of factors, like their exposure to weather, if they’re shaded by trees or buildings, and more.

To ensure your solar panels have a long life, you should ensure that they are regularly monitored and seek professional assistance when it comes to making any repairs and conducting inspections.

With a good amount of care and attention, monocrystalline panels can last up to 40 years, while polycrystalline models can last up to 35 years, and thin-film solar panels can have a lifespan of around 20 years.

Additional guidance and tips on all things solar are available in the solar section of our blog. So, if you want to know if solar panels work in winter, how many solar panels you need for your home, and the grants available to help you pay for your solar system, we have all that and more. 

Solar panel installation with BOXT

With BOXT, not only will you get a solar panel system that drastically reduces your energy bills and your carbon footprint, but you’ll also get 12-year product and 25-year performance warranties for complete peace of mind. What's more, we have a range of finance options available, and our team can install them within as little as 2 weeks.

Get started by filling in our easy online form, and we'll provide you with affordable solar panel quotes tailored to your home.