UNTHA UK sales director, Gary Moore, recently spoke to Circular about solar panel recycling. If you missed it, you can read the article in full, here…

By Gary Moore, sales director at UNTHA UK

April has seen the UK Government publish its eagerly anticipated energy strategy, announcing bold commitments to accelerate the deployment of clean energy – and one key area featured is solar.

While solar panels themselves have been around since the 1950s, an official report outlines that only 3.3% of the UK’s 29 million homes are generating electricity in this way.

It’s clear that the new strategy aims to change this – detailing plans to boost the UK’s current 14GW solar capacity up to five times by 2035.

But despite there being greater encouragement to adopt renewables and create a low-carbon economy – and rightly so – it’s important that key governmental and industry decision-makers also think about the long-term future of these installations.

For instance, what will happen at the end of their life and how can they be recycled? 

These questions need solutions defined at the start of a project, so that this ‘green’ technology doesn’t end up becoming yet another landfill pollutant, when it’s served its original purpose.

The state of solar in the UK

In the UK, there are 970,000 homes with solar panels and just under 500 solar farms, meaning it’s not the most advanced nation when it comes to adopting this renewable energy stream – China and the USA scoop the top spots. But with the new British Energy Security Strategy, it looks like the tide is set to change.

As part of this long-term vision, and in a bid to help drive the adoption of cleaner, greener home improvement technologies, the Government also announced that there would be a VAT cut on the installation of energy efficiency projects – like solar panels – for the next five years.

It’s also been proposed that there will also be the creation of 10,000 jobs in solar power by 2028.

All these promises and measures are great news for the nation, in helping to combat both climate change and the current hike in energy prices, but there are some unanswered questions around the recyclability of these items.

For instance, while domestic solar panels have a typical lifespan of 25-30 years, like with all other products, there comes a point in time when they reach the end of their life, and they need to be disposed of sustainably.

And with it being predicted that by 2030, circa eight million metric tonnes of retired solar panels could pile up globally, this question needs answering sooner rather than later.

Can solar panels be recycled?

The quick answer to this question is ‘yes’, however, there are some important points to note, as this waste stream does have unique characteristics that need to be considered.

While the materials used in the construction of solar panels – including aluminium, glass, copper, and silicon – are widely recycled, there are also certain components that require specialist handling. 

For example, in the UK, it’s illegal for solar panels to be landfilled – the Environment Agency requires the disposal route to fulfil certain legal requirement and standards, due to them sometimes containing small amounts of toxic materials, such as lead and cadmium.

And despite recycling being possible, there are two different main types of solar panel – silicone and thin-film based – and each one requires a different method.

With silicon panels, traditionally the first step is material separation – with the aluminium and glass elements being recycled and reused – before the remaining components are heated to evaporate the plastic. The resulting silicon cells and wafers then undergo further separation and processing.

This is in contrast to the more severe process for their thin-film counterparts, which are first shredded to remove lamination, before being size-reduced to a <6mm fraction. The remaining liquid and solid commodities can then be separated via a rotating screw before undergoing further processing to completely separate the various materials.

What roles does shredding play in solar panel recycling?

Shredding plays a pivotal part in the liberation of composite materials that could otherwise remain ‘locked’ within solar panels.

And by releasing these materials, it’s then easier for the downstream recycling equipment to do the best possible job for maximum reuse and recovery rates.

As a result, this helps to preserve the earth’s rare elements that are used in the manufacturing of solar panels and also ensures that these products aren’t destined to end up in landfill.

A typical system supplied by UNTHA to process photovoltaic panels would consist of a feed conveyor, pre-shredder, vibratory pan feeder, discharge conveyor with neodymium cross-belt magnet for ferrous metals removal, a secondary shredder, an eddy-current separator (for non-ferrous separation), and Zigzag separation system for glass and plastic.

The future of solar panel recycling in the UK

It’s been reported that if recycling processes weren’t implemented, the earth would have 60 million tonnes of photovoltaic panel waste in landfills by the year 2050.

So, while coming to market with these renewable energy innovations is important for the world’s resource agenda, it’s equally vital that the wider supply chain innovates at the same pace and that a fit-for-purpose infrastructure is in place to handle the increasing volume of these products.

And ultimately, without a recycling strategy in place for such products, these sustainable and forward-thinking technologies ironically become the very thing they’re trying to avoid – a pollutant.

It’s down to waste and recycling professionals to collaborate and help guide industry decision-makers in the most efficient and effective ways to handle these complex waste streams, in order to make the Government’s bold clean energy ambitions possible and not just a pipedream.