How Long Does a Solar Panel Last in Ireland?

How Long Does a Solar Panel Last

If you’re worried about the rising cost of electricity, you’ve probably asked yourself about the effectiveness of solar panels. By 2030, the Irish government aims to have 250,000 rooftop installations completed, with the country producing 80% of its electricity needs from renewable sources. There’s still a way to go to achieve these green ambitions. However, by the end of 2022, it’s forecast that around 5% of Ireland’s electricity demand will be met by solar panel sources. But how long does a solar panel last? A modern solar panel can last between 40 and 50 years; however, solar panels that were installed within the past few decades will have a lifespan of around 25 years.

Ready to join the green revolution? Solar panel installation is more affordable than you might think. Not only will it provide you with energy savings in the short term, but you can also mitigate the outlying cost by taking advantage of SEAI grants. Do you still need convincing that solar panels are an excellent long-term investment in Ireland? Read on for everything you need to know.  

How Long Does a Solar Panel Last Before it Needs Replacing? 

As mentioned earlier, between 40-50 years.

“Most manufacturers provide warranties to cover solar panels for around 25 years,” says Martin Desmond, the Managing Director of Wizer. “During this warranty period, a high-quality solar panel shouldn’t experience too many performance issues.” In fact, a premium solar panel should continue to perform at 80% efficiency, long after the warranty period ends.

It’s worth remembering that solar panels are a fairly new technology. As such, it’s hard to give a clear estimate of the maximum lifespan of a solar panel. So, when asked how long does a solar panel last, the exact answer is completely unknown. It may turn out that many systems will continue to deliver for many decades. Taking the prototype solar cell first designed circa 1954 as a prime example, this piece of solar history still works just fine today, and that’s after spending about 18 years locked in a drawer in a London museum, so the story goes. 

What Happens Next? 

Around 50,000 homes in Ireland are equipped with solar panels, with most of these systems having been installed over the past decade or so. These solar panel statistics don’t even consider the number of commercial PV systems in operation in Ireland. Solar panels in Ireland are likely to become even more widespread, with more homeowners and businesses looking to offset rising energy costs.

Because PV technology is still new, there isn’t a huge amount of data about how well solar panels perform after 25–30 years. However, just about every system will experience a slight decrease in efficiency over the years. Historically, a typical solar panel would have experienced degradation rates of around 0.8 per cent every year. However, PV technology has come a long way in a short time. 

When exposed to high levels of UV exposure, modern solar panels can experience degradation rates of around .7% every year. However, solar panels with an enhanced warranty will experience a decline of no more than 0.2% annually. Are solar panels worth it in Ireland? Although the country might not be known for its sunny conditions, it boasts the perfect climate for extending the lifespan of solar panels.  

Extending the Lifespan of Solar Panels

There are several ways to help increase the lifespan of your panels such as below. 


How long does a solar panel last? In many cases, the answer lies with the quality of their inverter. Older solar panels are usually equipped with string inverters. Generally speaking, panels with string inverters will only perform optimally for around 10 years before you notice drops in efficiency.

Furthermore, string inverters tend to limit the amount of energy you can capture and process. Inverter inspection is a key part of solar panel maintenance. If inverters aren’t regularly serviced, you’ll never get the maximum benefits from your PV system.  

Regular Maintenance

If you’re wondering how long a solar panel last, you should be thinking seriously about maintenance. “Although PV technology is largely self-reliant, occasional maintenance is essential to ensure they continue to perform well for years to come,” Martin Desmond says. “Once your solar panels have been installed, you should aim to have them inspected and serviced by a professional at least once every 12 months. If you’ve invested in a larger array, it might be an idea to arrange a biannual service.”  

Occasional cleaning is at the heart of any solar panel maintenance routine. For best results, aim to clean your panels at least once every six months. However, there are times when more regular cleaning may be required. Rainy weather provides panels with an all-natural rinse, so you’ll need to keep an eye on extended dry spells. Have your solar panels in Limerick not experienced a drop of rain in weeks? Carrying out a quick manual clean is a good idea.  

Solar Panel Cleaning Tips 

When cleaning solar panels, take care not to damage the panels’ surface. Get rid of any surface debris like leaves by gently brushing it away with a soft-bristled brush. If you need to get rid of more stubborn debris, don’t be afraid to reach for the garden hose. However, remember that hoses should only ever be used in a low-pressure setting. 

If there are patches of grime that won’t budge, it’s time to reach for soft cloth and a bucket of warm water. You may have to apply some elbow grease here but take care not to leave any scratches as you cut through all that grime.  

More Essential Maintenance Tips 

Don’t be tempted to clean the wiring underneath the surface of the panels themselves. How long does a solar panel last when its wiring has been exposed to water? The answer is, not very long. Water exposure can wreak havoc on internal connectivity, severely limiting the efficiency of your panels. These components should only ever be accessed by someone who knows what they’re doing during a professional service.  

If your panels aren’t providing you with adequate output, consider your surroundings. Do solar panels work on cloudy days? They do, so if you’re noticing any lags in efficiency, the cause is something else entirely. 

Have you invested in solar panels in Waterford? Are you situated in a leafy area of the city? Overhanging branches can leave your panels in the shade, limiting the amount of UV exposure they receive. What’s more, low-hanging and falling branches can potentially damage your panels. For peace of mind and enhanced performance, you’ll want to cut any branches back.  

What Happens to Decommissioned Solar Panels? 

Eventually, even the best solar panel will need to be replaced. However, this doesn’t mean that a decommissioned panel must end up in a landfill. Around 95% of the glass used to produce a silicon-based solar panel can be recycled. What’s more, all metal parts can be reclaimed for future use. Thermal processing is then used to separate the remaining silicon, with around 85% of this material able to be recycled.  

For thin-film-based solar panels, the approach to recycling is radically different. For starters, spent panels are shredded. This shredded material is then milled down to tiny particles, allowing for the liquid and solid parts of the material to be separated. The liquid goes through an extensive purification process, ensuring that around 95% of the semiconductor material can be reclaimed. Vibration and rinsing processes are used to purify the solid elements. By the end of this stage, around 90% of the original glass elements can be reclaimed for other uses.  

Getting the Most From Your Solar Panels

How Long Does a Solar Panel Last

Today’s solar panels should perform well for at least 25 years before you notice any significant dips in efficiency and output. However, PV technology is advancing all the time. If properly maintained and regularly serviced, modern solar panels should perform well for upwards of 40 years.  

There’s also plenty you can do to extend the lifespan of your solar panels. Regular inspection of output is a must. You can use a monitoring system or refer to your inverter to identify any issues. A high-quality inverter is another essential. Panels equipped with second-rate string inverters are only going to perform optimally for around 10-15 years

Once you’ve had your system professionally installed, it’s worth investing in solar panel servicing once every 12 months. This way, you’ll get a heads-up on any minor problems before they become something more serious. You should also aim to clean your panels once every six months. 

However, if you’ve experienced a long spell of dry weather, it’s time to reach for a soft-bristle brush and damp cloth. Be delicate when cleaning panels to avoid leaving surface scratches. 

Finally, think about pruning any nearby trees to ensure your solar panels aren’t left in the shade.  

Speak to Us About Solar Panel Installation Today 

Tired of paying over the odds for energy? Now’s the time to think about solar panel installation. At Wizer Energy, we’re the go-to provider and commercial and residential PV systems. Looking for solar panels in Cork? We can help. Thinking about solar panels in Dublin? Our team will make the quick work of installing a low-impact PV system that’s right for you.  

Looking for more energy-efficient solutions? Why not speak to us about infrared heaters or an EV charger installation? If you’re thinking about going all-electric, we also provide Zappi chargers in Ireland. Use the online form to drop us a message today. Alternatively, give us a call at +353 83 080 0855. 


How often do solar panels need replacing?

This depends on several factors. However, most solar panels should perform well for 25-30 years. Many solar panels produced today are expected to last upwards of 40 years. Most solar panel manufacturers offer a warranty period of 25 years. While panels themselves have a long lifespan, you will need to replace solar panel batteries once every 5-15 years.

Do solar panels lose efficiency over time?

Although solar panel technology is becoming increasingly sophisticated, even the best solar panel will lose efficiency over time. Generally speaking, the efficiency rating of a solar panel declines by approximately 0.5% for every year of use. In other words, a typical solar panel will be around 15% less efficient after 30 years of use.

What happens after 25 years of solar panels?

Even though many solar panels come with a 25-year warranty, they won’t stop working after this time. While some degradation is to be expected, your solar panels should continue to produce electricity beyond this point. However, they’ll do so at a lower rate. Many factors affect degradation, but if your panels continue to work efficiently, you shouldn’t need to replace your system.

How many solar panels does it take to power a house?

This all depends on the size of your property. A one-bedroom house with limited electricity needs should only need six panels to meet your power consumption requirements. However, if you’re looking to power a three-bedroom property, a 10-panel array is a better choice. If your annual consumption is closer to 10,000 kWh, a 20-panel system may be required.

Why do solar panels stop working?

It’s natural for solar panels to degrade and become less efficient over time. However, other factors can cause them to stop working. If your solar panels aren’t cleared regularly, accumulated pollen, dust and other debris can prevent them from receiving sufficient sunlight. Malfunctioning inverters and solar meters can also cause issues. Sometimes, panels become damaged. Microscopic cracks often go unnoticed until thermal effects make them more visible, often requiring you to replace a panel entirely.

At what temperature do solar panels lose efficiency?

Although modern solar panels are better at withstanding temperature extremes, you will notice a slight drop off in efficiency on hotter days. Most panels are tested at temperatures of 25 °C. If outdoor temperatures climb higher than this, a slight drop in efficiency is to be expected. In most cases, an efficiency loss of 0.35% for every degree can be observed.

Author Bio

Slaven Litera

Having worked as a high-voltage power technician since 2007, Slaven Litera is Wizer’s Director of Operations. With over 15 years of experience in both commercial and domestic high voltage systems, Slaven made the transition to renewable energy in 2017. During his tenure as the lead engineer at one of Ireland’s biggest solar panel installation companies, Slaven provided end-to-end services. From pre-installation site reviews, to full commissioning and testing of new power systems, Slaven has done it all. In fact, throughout his career, Slaven has overseen and installed over 1000 individual solar PV installations amounting to over 1.2MW of solar generation! Holding electrical qualifications in multiple European countries, he continues to expand his knowledge in renewable energy sources. As Wizer’s Director of Operations, Slaven’s highly driven nature is the force behind creative and “out of the box” solutions at Wizer. Since his experience is so diverse, there’s virtually nothing he hasn’t seen before!

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