From sun to scrap: The impact of solar waste

KUALA LUMPUR - Solar power is expected to make up nearly 60 per cent of Malaysia’s energy mix by 2050. Around 164 million solar panels will be installed to make this happen, but where do they go when they die?

To the landfills, most likely.

But consider this: solar photovoltaic (PV) panels, especially ones used commercially, can be big, bulky and heavy. They weigh in at 20-40 kg per panel.

Now imagine those panels taking up space at landfills, along with old furniture and decades of solid waste.

Malaysia already has inadequate land for landfilling.

As of 2021, the National Solid Waste Management Department recorded 137 landfills were currently in operation. In a report by Bernama last year, local agencies and environmentalists warned that there will be no space left in Malaysia by 2050 if efforts weren't made to reduce the country’s waste.

Between 2020 and 2021, Malaysia’s solid waste increased by 5.2 per cent, from 13,709,546 to 14,426,731 tonnes. Most of the waste has gone into landfills.

The scenario is more than a little worrying because Malaysia has yet to come up with a solid plan of how to deal with the upcoming solar waste glut. Unless it does in the very near future, the country could be looking at improper disposal of decommissioned solar PV panels.

This is not something that should be taken lightly. Aged out solar PV panels can leach toxic chemicals and carcinogens into the environment. They are also potentially radioactive.

To understand the kind of pollutants that could come from a solar panel, let’s take a look at a breakdown of its components.

WHAT’S IN A SOLAR PANEL?

Three types of solar PV panels dominate the global market: monocrystalline, polycrystalline and thin film.

The majority of the local solar energy solutions providers, however, use monocrystalline panels. These panels are made from single-crystal silicon (meaning each cell is cut from a single, pure crystal of silicon.) Single crystals allow electrons more space to move for better electricity flow, making these panels higher in power efficiency than other types of solar panels.

What’s in a Monocrystalline Solar Panel

Silicon Cells: The cells contain single cylindrical crystals made of silicon wafers of high purity that act as semiconductors.

Glass Layer: The front of the panel is covered by a durable, transparent glass that protects the silicon cells from environmental conditions while allowing sunlight to penetrate.

Backsheet: A protective cover for the back of the solar panels. Made of PET (polyethylene terephthalate) or PVF (polyvinyl fluoride) polymeric laminate.

Frame: Typically made of aluminium, surrounds and supports solar panel components.

Helps extend panels’ lifespan by protecting its edges and making installation easier.

Encapsulation Materials: Silicon cells are typically encapsulated in EVA (ethylene-vinyl acetate) or other encapsulant materials to provide additional protection against moisture and mechanical damage.

Junction Box: Located on the back of the panel. Houses the electrical connections and is sealed to prevent moisture and prevent electrical shorts. May contain cadmium, barium, nickel, copper and even lead.

TIMELY REGULATION PREVENTS DUMPING

Malaysia currently has yet to come up with policies or regulations on the management of solar panel waste. It has not even classified the type of waste it is, impeding recycling.

The President of the Association of Water and Energy Research Malaysia S. Piarapakaran finds this concerning.

"There is currently a low level of awareness on this matter. Imagine in 10 to 15 years, we will need to start disposing of the solar panels that are currently in use.

"How are we going to handle them in view of the lack of policies, regulations, mechanisms and facilities? This could eventually lead to rampant illegal dumping,” he tells Bernama.

The reason why regulations have yet to be formed is probably due to the limited installation and usage of solar PV in Malaysia, which when combined with other forms of renewable energy totals up to nearly four per cent of the country’s Total Primary Energy Source in 2023.

But it isn’t that the country has not started work on the matter yet, the Minister of Energy Transition and Water Transformation Datuk Seri Fadillah Yusof tells Bernama in an interview.

"SEDA is actively engaged in a study on how to manage solar panel waste. We anticipate that the results will offer valuable insights, providing the government with policy options for handling the end-of-life phase of solar systems,” says Fadillah, who is also the Deputy Prime Minister.

SEDA, or the Sustainable Energy Development Authority, is the body that manages the implementation of the feed-in-tariff mechanism in Malaysia.

HEALTH CONCERNS

But solar panel waste needs to be managed or it will have a domino effect, says the International Renewable Energy Agency (IRENA), an intergovernmental agency for energy transformation.

"Much like other forms of electronic waste, the lack of proper regulation for end-of-life panels may lead to their disposal in landfills, potentially resulting in adverse environmental impacts,” Ute Collier, an acting director at IRENA tells Bernama. "This is particularly concerning when hazardous materials, such as lead and nickel, are released into the land or water.”

Piarapakaran echoes these concerns.

"End-of-life panels that have lost their waterproofing capabilities may cause the chemicals within the solar panel to leach if exposed to rain and shine. The leachates may then contaminate the soil, groundwater, and surface water as well,” he says.

He also highlighted the increased risks faced by areas located near dumping sites containing solar panel waste.

"Once these leachates are mobile, it will take time to make an impact. Areas closer to plantations, river basins used for irrigation, drinking water sources as well as homes to aquatic life are more vulnerable,” says Piarapakaran.

Non-urban communities are at greater risk, he adds.

"Rural folks use groundwater as an alternative source of water. Thus, contaminated groundwater poses a direct risk to these places,” says Piarapakaran.

A 2020 study from India lists arsenic, cadmium and lead as the "top three solar PV-associated carcinogens”. They reviewed research that looked at metal content and metal leaching from solar PV waste between 2000 and 2018.

Lead was seen to have the highest leach rate, but this could be due to it being present in a higher quantity (0.67 per cent) in crystalline silicon modules compared to cadmium (0.05 per cent) in thin-film modules and the limited results found for arsenic.

The study also showed that if solar PV waste were to be dumped into a municipal solid waste landfill, pollution potential of that landfill would increase by 5.15 per cent.

Moreover, long-term leaching can lead to the leakage of large amounts of toxic elements from PV modules, states a 2021 German study. The study looked at long-term leaching in solar PV modules with weak spots over a period of one and a half years. Tests were done on crystalline silicon (c-Si), amorphous silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium diselenide (CIGS) modules.

Most if not all, the toxic elements leached due to delamination (separation of layers) in all tested modules. Modules that were cracked, crushed or milled and ended up in landfills also had a high-risk of leaching.

Another study from India published just this year on end-of-life solar PV panel waste management showed that improper disposal of panels at landfills were similar to existing cases of e-waste disposal; it would cause the leaching of lead and cadmium into groundwater, worsening the groundwater quality.

POTENTIAL RADIOACTIVITY

It isn’t just leachates that are of concern with decommissioned solar panels.

SIRIM, an agency which promotes and undertakes scientific industrial research, has found that there are parts of a solar panel that can become radioactive with age. The organisation has initiated a recycling project with a prominent industry player.

This occurs when the silicon and metal content reacts to moisture and the harsh outdoor environment, says its Director of New Business Management, Muhammad Firash Abdul Fattah.

"Solar panels absorb solar energy and ultraviolet rays, which they convert into energy. However, not all 100 per cent of it is converted into electricity. The efficiency in the early stages is only at 20-25 per cent, and that gradually reduces over the years.

"This excess of 70-80 per cent, where does it go? It stays in the solar panel. If for the next 25 years it is exposed to the sun's rays, there is a possibility of radioactivity,” he says.

At greatest risk are workers who are involved in the removal of these panels.

"Let’s say we have 15 solar panels here in SIRIM’s office, and all of them have come to their end of life. Removing all of them, putting them into trucks to be transported out can be hazardous to a human being.

"Is it going to kill a person? No. But is it going to poison the handlers who have been consistently exposed to solar panels over the years? Yes,” he says.

POTENTIAL MISSED OPPORTUNITY

Without proper handling of end-of-life solar PV panels, Malaysia could also be missing out on opportunities to save on raw materials. This is borne out by lots of research into more mature solar PV panel markets outside of Malaysia.

Solar PV panels contain valuable materials that can be recycled and reused into new panels. If these materials are not recovered through proper recycling techniques, there will be a need for virgin resources for the production of new panels.

This was confirmed in a 2018 study from China on the global status of recycling solar panel waste. It found that end-of-life solar PV panel recycling could not only save natural resources, it reduces production costs. Such recycling efforts provided a large number of semiconductors and other raw materials for the usage of the solar panel industry.

Research from Thailand in 2019, meanwhile, showed that the decision to send silicon-based panels to landfills would result in the total loss in recovering valuable materials such as glass, copper, aluminium, silicon and silver. It also highlighted the energy-intensive and environmentally harmful costs of extracting, refining and casting these materials.

There is currently a high reliance on using raw materials in the absence of recycling efforts. According to a 2023 Indian research paper, implementing PV panel recycling and reusing the recovered materials could potentially reduce 60-90 per cent of PV waste. This is in addition to lowering the demand for virgin materials needed to produce panels.

The cost of recycling solar panel waste is a small price to pay when it comes to the long-term benefits - not just on the environment but in the prevention of a potential public health crisis.

But all of these can only take place with well-timed policies. Regulations must be put in place long before the solar waste glut comes. Preventative measures have time and again proven to be more cost effective than curative ones. - BERNAMA