When we think about solar, we visualize sleek solar arrays laid out on rooftops and large commercial spaces. We think about green energy, technology and the impact of conscious consumption of power on our planet. One aspect of solar that we often overlook is — what happens to solar modules after the lifespan of a solar project? How much of solar panels are we recycling?

Typically, solar projects last approximately 30 years. The good news is that a German manufacturer is building the world’s first industrial sized solar recycling plant!

The news on phys.org is:

With strong competencies in plant manufacturing and wastewater treatment including recycling, the Geltz Umwelt-Technologie firm has built a test and treatment facility at a large disposal firm to retrieve reusable materials from solar modules.

 

The Lifespan of Solar Panels

Studies report that during the life of photovoltaic panels, generally, a 20 per cent decrease in power capacity occurs. In the first 10 to 12 years, the decrease in efficiency is 10%. This efficiency decrease rises to 20% when reaching 25 years. Majority of manufacturers guarantee these figures.

However, in reality, the efficiency drops by only 6 to 8% after 25 years. Which means that the actual lifespan of solar panels may be much longer than officially stated. For high quality PV panels, the lifespan may even reach 30 to 40 years, after which they might still be functional, although with decreasing efficacy.

 

What Happens to Solar Panels After Their Lifespan?

From a regulatory aspect, PV panels are defined as e-waste in the Waste Electrical and Electronic Equipment (WEEE) Directive. Like everything else, if recycling processes were not established, there would be a lot of waste in the environment. Fortunately, by recycling solar waste, we prevent the possibility of 60 million tons of PV panels waste lying in landfills by the year 2050.

Some components of solar panels, such as glass and aluminum, are recycled after their lifespan. However, we have been unable to recycle valuable minerals that make up the heart of the module themselves, until now. Fabian Gelz, a spokesman for GUT, said:

Up until now, there has not been any technical solution to recycle and separate the valuable materials from the mixed scrap. The critical step in the recycling process is therefore the destruction of the polymer layer.

 

Geltz Umwelt-Technologie’s Recycling Plant

According to the article, “ELSi came up with a novel solution to address this key issue. Using an energy-efficient pyrolysis process, project partners managed to dissolve the undesired polymer layers and easily detach the glass in the panels. This novel advanced process enabled them to successfully separate and recover aluminium, glass, silver, copper, tin and silicon in their pure form.”

During the process of isolating and classifying materials, the fine materials were separated by sieves and air classifiers. To treat the exhaust gases of the mechanical process, project partners used a thermal afterburner and a quench system with a gas scrubber.

The article mentions that at its current capacity, the plant will be able recycle as many as 50,000 solar modules a year and recapture 95% of the materials — which can be used as raw materials again.