Germany has stood at the vanguard of solar energy adoption for decades. Now, as older solar panels begin to reach the end of their life, Germany will once again be at the forefront—this time to answer the question: What are we going to do with all the solar panel waste?
Eyes are on Solar Energy to Address Climate Concerns
At the end of October, the United Nations climate summit, COP26, will kick off in Glasgow, Scotland. The two-week conference that will bring together nearly 200 world leaders and 20,000 delegates, activists, businesses, non-government organizations, and faith groups will seek to hammer out means to reverse the trajectory of greenhouse gas emissions heating the planet and to achieve ‘net zero.’
Solar power, which the International Energy Agency’s (IEA) most recent World Energy Outlook states is now the ‘cheapest electricity in history,’ is likely to feature prominently. The report shows that today’s solar electricity is 20% to 50% cheaper than their 2019 estimates and can generate electricity at or below $20 per megawatt-hour (MWh). These costs are comparable to those of existing coal plants in China and India and are even better than those of new coal-fired power plants.
Aging Tech Heralds a Coming Waste Crisis
But, along with this optimism, there is a very real concern for the future. Will industries be able to recycle the increasingly large numbers of photovoltaic (PV) panels that will inevitably be produced?
There are warnings that recycling capacity in Germany, the biggest solar power producer in Europe, may struggle to deal with the expected rising tide of PV waste. Some 4.5 million metric tons of PV modules are understood to have been installed across Germany to date, according to Germany’s Federal Environment Agency (UBA). The bulk of these was built and came into operation between 2010 and 2012 under Germany's Renewable Energy Act (EEG) that was introduced in the year 2000.
These early installations have now started to lose support funding. With an estimated twenty-five-year lifetime, their decommissioning looks to ramp up in the second half of the 2030s. This timeline may even be shortened due to faster than expected degradation. New research from the risk management firm kWh Analytics released in June finds that solar panels in use degrade twice as fast as industry claims with annual degradation rates in the field observed at around 1% lost capacity per year. Remondis, the largest waste management company in Germany, also reported that nearly all modules in 2020 were trashed due to malfunction or damage, not because they reached the end of their expected life.
Recycling Strategy Starts with Policy
Fundamentally, Germany already has certain policies in place to address the mounting challenge. Its Electrical and Electronic Equipment Act is based on the European Waste from Electrical and Electronic Equipment (WEEE) directive originally introduced in 2002 and provides a framework to handle end-of-life PV panels. Under the scheme, producers or distributors of PV are obliged to collect and recycle at least eighty-five percent of the modules, by volume. Further, old panels are to be treated separately from other residual waste.
Complexities of Solar Recycling
In practice, old PV panels are complicated to recycle due to the range of materials used in their assembly.
Typical crystalline silicon (CS)—the dominant semiconducting material used in PV technology for the production of solar cells—panels contain (by relative material value): 47% silver; 26% aluminum; 11% silicon; and 8% each copper and glass. Aluminum and silver are among the most valuable components that can be retrieved and recycled.
However, in contrast to aluminum and silver recycling, establishing an economically viable recycling procedure for glass has proved more difficult. Collecting and reprocessing glass is expensive while the value of the recycled good is low. Improving the efficiencies of this process is a critical point that needs further development.
Trashing solar panel waste would cause untold environmental destruction, but recycling materials economically is proving to be a serious challenge. Further development is needed to improve the cost of available recycling technologies.
A study published in Harvard Business Review (HBR) of the economics of solar power recycling notes, “They are mostly made of glass, an extremely low-value material.” The low cost of glass makes it ten to thirty times more expensive to recycle solar panels than to send them to the landfill. The study goes on to say that the volume of waste produced may even exceed the volume of new installations by 2031 at the current rates of production.
As if the growing quantity of PV waste wasn’t bad enough, the toxic nature of solar panels compounds their environmental impact. Writing in Forbes, Michael Shellenberger argued, “Solar panels are delicate and break easily. When they do, they instantly become hazardous and classified as such, due to their heavy metal contents.” Having a hazardous waste classification carries with it a string of expensive restrictions including its transportation, he points out.
Germany’s environmental agency has stated that recovering key materials used in panel production—especially silicon, tellurium, or indium—is still not viable. For trace components, the recoverable quantity at this time is simply too low.
Will Growing Investments Bolster Solar Energy’s Weaknesses in Time?
These concerns notwithstanding and despite the very real difficulties in accepting and treating the flood of solar panel waste that threatens to swamp Germany and the rest of the developed world, the market for solar panels is still expected to rise. Many environmentalists and energy organizations see climate change as the ‘greater evil’ and afford the goal of reaching ‘net zero’ emissions a higher priority than the thorny question of PV waste.
The International Renewable Energy Agency (IRENA) says that Germany, Europe, and the rest of the world will need to build many more solar power arrays in order to reach ‘net zero.’ Allied Market Research predicts substantial growth in the global solar energy market—from a valuation of $52.5 billion in 2018 to $223.3 billion in 2026. Meanwhile, reportlinker.com forecasts a rise in the global solar panel recycling market’s size from $206.19 million in 2020 to $405.44 million in 2026.
Investment in solar energy and recycling continue to rise. As raw resources become scarcer, recycling materials will be the key to a robust solar industry in the future.
In 2019, nearly 600 gigawatts (GW) of capacity in the form of millions of solar panels had been installed globally. But IRENA says this needs to grow about 18-fold and reach more than 8,000 GW by 2050 to make the world's energy systems compatible with international climate targets. It also believes that, despite some of the concerns voiced about the collection and costs associated with expanding the recycling infrastructure, PV recycling rates will inevitably rise as the technology improves.
IRENA points to one significant advantage in the use of recycled PV materials, in preference to primary raw materials: recycling enables producers to scale back mining of already scarce resources. It is believed that the world's PV industry could be using up to fifteen percent of the total global mining output of silver. The US Geological Survey has also expressed worries about the availability of tellurium and indium where it says material use has “exceeded annual production levels,” as more and more of these materials are used in the growing stock of electronic equipment.
*Nnamdi Anyadike is an industry journalist specializing in metals, oil, gas, and renewable energy for over thirty-five years.