As the shift toward a greener society continues, the demand for solar energy in UK homes continues to grow. While a report from Green Match found that installing solar panels could save the average home up to £1,005 a year in bills, installation and maintenance costs remain the key factors deterring many homes from switching to green energy.
But how long do solar panels last? With the typical cost of installing a standard 4kw solar panel system and a battery ranging between £14,000 and £20,000, customers are keen to know how long they’ll get out of the panels before having to pay for repairs and replacements.
That’s why we’ve put together this guide covering the average lifespan of solar panels, along with key facts and maintenance tips to help ensure your solar panels last longer.
How long do solar panels last on average?
The average lifespan of solar panels before they show significant signs of degradation is around 25 years. Even after that point, many panels can still convert sunlight into solar energy, but this is usually at a much less efficient rate than you’d get in the first few years after installation.
While it’s rare for a solar panel to stop producing energy completely, the efficiency eventually declines to the point that they’re not providing the savings on bills like they once were. At this point, it’s probably best to replace the panels entirely.
While 25 years is a good estimate for the average home, the lifespan of a solar panel can be enhanced or decreased by numerous factors, which we’ll cover below.
What are the main factors affecting the lifespan of solar panels?
While there are some factors, such as adverse weather events, that are beyond your control, there are numerous variables that you can control to ensure you get the most out of your solar panels. They are:
Solar panel quality
The quality of the solar panels you buy can play a pivotal role in their longevity. Solar panel manufacturers are divided into three tiers based on the quality of their panels. Tier 1 panels are the highest quality and typically most expensive panels, while tier 3 panels are usually the lowest quality and cheapest in price.
To be considered a tier 1 panel, the manufacturer must have:
- Manufactured their own solar panels, not outsourced them
- Used the best quality materials, especially silicon
- Used automated manufacturing processes to ensure quality
- Been active for at least five years, with a track record of producing quality panels
Checking the grade of a panel along with the materials used before buying can be a good way of informing the quality of a product. Often, the most well-known manufacturers will offer warranties of 25 to 30 years, showing their confidence in the longevity of their products.
Installation
Hiring a qualified and experienced installer to fit your solar panels can have an impact on their longevity. Poorly installed panels can degrade faster, and faulty wiring can lead to energy loss or even system damage.
Therefore, ensuring your panels are installed right the first time can prevent problems from occurring further down the line.
Climate
The climate of where you live can play a significant part in how long your solar panels last. Heat causes solar panels to degrade over time, so it’s likely that your panels will degrade quicker if you live in a hot climate, as opposed to somewhere colder.
Other weather conditions such as hail, humidity and regular strong winds can cause damage to the panels and reduce longevity.
Maintenance
Though solar panels are fairly low-maintenance, you can extend their longevity by taking care of them at home. Regularly cleaning the panels helps prevent a build-up of debris. Excess debris can reduce efficiency by blocking the sun and damage the panels by scratching and chipping them.
By cleaning the panels regularly, you increase the likelihood that they’ll perform at full capacity for longer.
What is the degradation rate of solar panels?
On average, a solar panel typically degrades at a rate of between 0.5% and 3% per year, depending on the type of panel and the conditions it has been kept in. This means that, after 25 years, many solar panels will have experienced degradation rates of anything between 12.5% and 75%.
Therefore, a good quality, well-maintained panel with a 0.5% degradation rate would still be operating at 87.5% of full capacity after 25 years.
How can I tell if my solar panels need to be replaced?
The performance of your solar panels is a key indicator of whether they need to be replaced. If you're finding that your energy bills are rising unexpectedly, it’s possibly a sign that your panels are operating less efficiently than they once were.
In this instance, it’s a good idea to get a qualified solar panel operator to assess the panels and decide whether repairs or a full system replacement is required.
It’s also worth having routine inspections of your panels every few years to check for physical damage or system faults. Even if the panels appear to be operating at full capacity, you want to mitigate against faulty equipment that could cause fires or damage if left unchecked. This is particularly true if your solar system is one of the many that relies on high-voltage DC electricity.
How can I make my solar panels last longer?
Solar panels are a big investment and you’ll no doubt want to ensure you get as much value as possible out of your purchase. While certain variables cannot be controlled and eventual degradation is inevitable, there are certain things you can do to ensure your solar panels last as long as possible.
Regular cleaning
Cleaning solar panels regularly benefits both their performance and longevity. Cleaning excess debris and other foreign objects off the panels will prevent sunlight from being obstructed and ensure maximum efficiency. Equally, cleaning regularly gives you a better chance of removing harmful materials and substances from the panels that could damage them over time.
Regular servicing
Having your solar panels regularly serviced by a reputable professional allows you to discover potential problems early. By doing so, you can take the appropriate measures to fix issues and prevent problems that could cause greater damage to your panels over time.
Keep out of the shade
Solar panels lose their efficiency when kept out of sunlight, resulting in them drawing energy from other panels and thus reducing the power of the overall system. Ensuring that all panels are directly facing the sun and are not blocked by trees or obstructive objects will help them continue operating to full capacity.
FAQs
How many solar panels are needed to power a typical house?
The amount of solar panels needed to power a home can vary considerably based on the size of the property. Typically, the average one-bedroom house needs around six solar panels, while a standard three-bedroom house requires 10 panels.
How long does it take for solar panels to pay for themselves?
The point at which your energy bill savings offset the cost of your solar panels can depend on an array of factors, including:
- The cost of your solar panels
- The electricity cost in your area
- Any additional maintenance or repair costs on your panels
Green Match reported that the average break-even period for solar panels in the UK is 9.5 years.
