How Long Do Solar Panels Last?

Solar panels are growing in popularity; they help reduce energy bills and positively impact the local and global environment. There is however, a catch — each and every solar panel out there has a finite lifespan, like any man-made object.

It's therefore essential to consider how long your investment in a solar system will continue to pay off, meaning you should consider the lifespan of your solar system. 

So how long can you expect solar panels to last? 

How Long Do Solar Panels Last? 

A conventional silicon cell solar panel has a lifespan of around 30 years, although thin-film solar panels don't last quite as long. 

Panel maintenance and climate conditions greatly influence solar panel lifespan. For example, regular panel cleaning helps minimize thermal differences across the panels; this, in turn, extends panel lifespan. 

Warranty Periods

Manufacturers offer two kinds of warranties:

  • Product warranty: typically lasts 12 years and covers product defects. 
  • Performance warranty: typically lasts 30 years and only covers the scenario when the panels degrade faster than the manufacturer's warranted rate. 

To Summarise

The standard lifespan for panels is 30 years. This timespan is the basis on which investors and banks finance utility-scale solar plants. As such, it's a solid enough estimate for your home or business's financial calculations.

Why Do Solar Panels Break Down?

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Solar panels typically degrade over time, like any man-made object. In fact, a slight degradation occurs when solar panels are initially exposed to light, known as light-induced degradation

Natural long-term degradation of solar cells causes a slightly lower output from the solar cells and, therefore, the solar panel.

Other Factors That Cause Panel Breakdown

  1. UV light: UV light degrades the panel material by embrittling the lamination. 
  2. Weather conditions: stress and abrade components (dust, high-temperature cycling, wind, snow). 
  3. Mechanical damage: hail, rough cleaning, and falling tree branches; these all cause mechanical damage, often cracking the delicate silicon solar cells or damaging the glass front sheet. 
  4. Corrosion: corrosive environments (for example, acid rain and salt air) will cause pitting, rusting, and oxidising aluminum frames or connectors. 
  5. Installation damage: damage, such as installers walking on the panels, can occur during installation and permanently degrade the solar panels. Don't let installers walk on your solar panels!

Solar Panel Degradation Rate: What Is It? 

Solar panel degradation rate refers to the reduction in peak power output when a solar panel is placed under standard solar conditions. 

Therefore, the degradation rate is the percentage of output lost each year compared to their initial (mint condition) state.

A typical degradation rate is around 0.5% per year. However, this statistic varies since every panel is slightly different, and the environmental conditions differ somewhat for each panel.

How Do You Know When Your Solar Panels Need To Be Replaced?

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Solar panels reach the end of their lifespan when their output is below warranty levels or their condition is poor. 

Panels in this state will often have:

  • Cracked and degraded lamination 
  • Damaged glass 
  • Hot cells 
  • Inconsistent output across the array 
  • Corroded and porous frame 
  • Rusty and non-functional electrical connectors

Inspection Is Key

You should have professionals visually inspect your array regularly, or do it yourself. This is especially important after a storm, as hail or snow may have damaged your panels. 

You should also check the array in spring so that any defective panels are replaced before the peak production period of the year. 

What Can I Do About It? 

There are several things you can do to protect yourself and improve the life of your solar system:

  • Only buy from well-known and financially stable solar panel brands. Panels from these brands are more likely to survive in the long run, and the companies can therefore honor their warranties. Bloomberg's top 10 solar brand list is helpful, although individual models of panels also matter. 
  • Store your warranty information in a safe place. You might need it, even if it's 25 years down the line! 
  • Have your system checked every year. Make sure an accredited solar system maintenance company does this. They can check your system data remotely and conduct visual and thermal imaging inspections. 
  • Visually inspect your array. Even climbing up a ladder and running an eye over the panels every few months will help keep an eye on apparent damage or soiling. 
  • Keep an eye on your array's output. Inconsistent output is a warning sign of panel degradation. 

Is It Possible To Extend Your Solar Panels' Lifespan?

While it's not possible to extend the maximum lifespan of your solar panels, it is possible to slow down their degradation rate.

Unfortunately, no. You cannot extend your solar panels' lifespan; you can only replace them.

How Do You Get Your Solar Panels Replaced?

Replacing your old solar panels is straightforward. All you need to do is contact an installer and get your system surveyed so they can assess the work required to replace the panels. The installer can then prepare a quote for you to consider. 

Once the installers have replaced your system, request proof of it being checked, tested, and its compliance with any local, state, or federal codes. 

What Will Happen To Your Old Solar Panels?

Solar panels face recycling challenge

There are a few options, depending on where you live. Hopefully, solar panel recycling is an option in your area. Otherwise, your solar panels will end up as solid waste in landfills. 

Recycling yields many local and national benefits, not the least of which is the recovery of rare strategic metals. In addition, recycling solar panels save energy, creates jobs, and reduces landfill. There are many solar panel recycling schemes in the US

Solar Panel Recycling Steps

  • Mechanical separation
  • Thermal processing 
  • Silicon wafer recycling

Material separation: solar panels are made of several different components, so these components are disassembled. The panel's aluminum frame and glass casing are taken apart. The aluminum frame and the glass front sheet can be almost totally recycled.

Thermal processing: the laminated solar stack is then placed inside an oven. At 900°F, small plastic components evaporate, and the silicon cells can be physically separated. Around 80% of the plastic is recoverable, although some of this plastic is used as fuel for the oven. 

Silicon wafers recycling: the solar cells are etched away and smelted into reusable silicon slabs. 85% of the silicon is repurposed for new solar panels, and 15% of it is lost in the process.

Thin-Film Panel Recycling

A separate process is used to recycle thin film panels due to the different materials in them. Thin-film panel recycling is essential because of the very rare semiconductors present in the panels. 

Final Thoughts

Solar panel lifespan is a crucial concern for homeowners considering buying a solar system; you can carry out number of simple things to maintain the lifespan of your solar system. 

The industry standard lifespan is around 30 years, but some brands out there do have lower-quality products. 

In the end, we suggest you speak to a local supplier and/or shop around.