Photovoltaic (or solar) panels have been popular clean energy and renewable power sources for many households for the past three decades. But with the oldest models set to expire, there’s about to be an influx of solar e-waste.
Solar panels provide us with an essential source of renewable energy to help combat climate control by minimizing fossil fuels. Unfortunately, they don’t come without drawbacks, and these complex sheets of technology fade to a heap of electronic waste that we have no idea how to process.
Do Solar Panels Produce Toxic Waste?
Solar panels contain toxic materials such as lead that can leak out of the panels as they break down in landfills, in a process that is hazardous to the surrounding environment. It is impossible to remove these toxic components without breaking apart the entire glass panel.
A large part of the problem is that people remain uninformed. Not many people want a nuclear power plant in their backyard, but they’re happy to install solar panels in their homes. For this reason, it may surprise you to learn that solar panels create 300 times the amount of toxic waste for every unit of energy when compared to nuclear power plants.
What Kind Of Waste Do Solar Panels Produce?
The main component of a solar panel is glass, which composes up to 75% of the total product. However, a solar panel can also contain heavy metals like lead, arsenic, and cadmium, classified as hazardous waste once they reach certain levels.
All brands are unique, so we can’t make sweeping generalizations about the waste of a solar panel; instead, we have to look at the different types to understand the hazards they pose.
Older silicon solar panels can be hazardous as they contain hexavalent chromium coatings. And newer, thin-film panels can also pose a hazard due to their levels of selenium and copper.
CdTe solar panels may contain harmful levels of cadmium, while GaAs or Gallium arsenide panels may contain hazardous amounts of arsenic.
How Much Solar Panel Waste Is There?
According to most manufacturers, the average lifespan of a solar panel is around 25 years. As solar energy was in relatively little usage until the early 2000s, there aren’t too many solar panels currently being decommissioned.
But the International Renewable Energy Agency (IRENA) projects that the global volume of PV panel universal waste could reach 78 million tonnes by the year 2050. At this point, the solar industry will generate an estimated 6 million tons of solar e-waste annually – a lot of which could be potentially hazardous waste.
What Materials Are Used To Make Solar Panels?
Solar panels comprise photovoltaic cells which convert the sun to electricity. Many panels on the market use crystalline-silicon technology with a board constructed from glass, copper wire, layers of polymer, and silicon solar cells.
These panels possess an aluminum frame and contain a plastic junction box. Plus, solar-powered systems may include inverters and battery backup systems.
Put simply; a solar panel is a kind of electronic sandwich with layers of silicon crystals sandwiched between a crust of glass with an aluminum frame. When these components are combined, they can convert sunlight to electricity.
The polymer layers protect the panel from weather exposure; however, they can make disassembling the panel a problematic task because high temperatures are needed to loosen this adhesive.
In addition, solar panels can contain critical materials such as tin, antimony, and gallium. The definition of critical materials is those which are vital for the national and economic security of the USA.
What Are The Environmental Impacts Of Solar Panel Production?
Federal data shows that the building of solar panels increases NF3 emissions significantly. NF3 or nitrogen trifluoride is an inorganic, toxic gas 17,200 times more potent as a greenhouse gas than carbon dioxide when measured over 100 years.
For the last 25 years, US data shows a carbon dioxide emissions increase of around 5%, while NF3 emissions have risen 1,057%.
The problem is that solar panels require very pure silicon to work effectively, and the production of this produces NF3 and sulfur hexafluoride, both of which are highly harmful greenhouse gases.
While manufacturers can often recycle silicon, they add cadmium to improve the product’s electrical efficiency, making the silicon less easy to repurpose.
What Are The Alternatives To Silicon-Based Panels?
With such a high environmental impact during production, companies have begun to examine ways to reduce the number of carbon emissions during panel creation.
One way to do this is to replace the pure silicon solar cells with a cleaner and greener alternative material. And a material known as perovskite could provide the answer. A perovskite solar cell comprises metal crystals (usually lead), but research has shown that non-toxic alternatives such as tin or germanium are almost as effective.
What Is The Waste From Solar Panels?
One of the biggest concerns for environmental agencies is that cadmium can wash out of solar modules that people have dumped into landfills. Not only that, but severe weather, such as tornadoes and hurricanes, can also pose a threat to these panels.
Residents of Spotsylvania petitioned heavily against the vast solar farm currently being constructed on 6,000 acres of their land. Not only is this land taken away from the natural inhabitants of the area, but the effects of a potential cadmium leakage could wreak havoc on flora and fauna.
When you consider that completed solar farms of this size will house around 1.8 million solar panels containing approximately 100,000 pounds of cadmium, you understand the potential hazard. Cadmium is a highly toxic substance that attacks the body’s cardiovascular, gastrointestinal, renal, respiratory, neurological, and reproductive systems; it can cause cancer.
Acute exposure can lead to lung infections and flu-like symptoms, while prolonged exposure can cause diseases in the kidneys, bones, and lungs.
These toxins, notably lead, can stay in the ground and accumulate over several years. They threaten the wellbeing of the plants and animals that rely on the soil for nutrients. In addition, the effects can be passed onto humans if we eat produce from the area. And affected soil can also contaminate groundwater.
The most significant risk of lead poisoning is stunted brain development, hazardous for children as irreversible damage occurs. In addition, high levels of lead exposure can cause damage to the nervous system and the kidneys – leading to seizures, unconsciousness, and even death in severe cases.
What Is The Life Span Of Solar Panels?
Most manufacturers of solar panels state that their product will last for around 25 years. Not only are we about to hit a boom of decommissioned panels thanks to the boom of panel installation two decades ago, but we also have to face the fact that many of these panels will not last for 25 years.
The first factor is breakages. Severe weather such as tornadoes or hurricanes can destroy thousands of solar farm panels like Hurricane Maria did to Puerto Rico in 2017. At the same time, solar companies have introduced preventative measures to create “hurricane-proof” solar panels, but damage is by no means impossible. Even rainwater can flush cadmium from a functioning solar panel.
Secondly, people will often choose to replace their solar panels before reaching their end of life. Owners weigh up factors such as the sunlight to electrical energy efficiency and how much the electric companies pay them.
A solar panel often diminishes productivity after the first few years, meaning the owner could be looking for a more effective product well before the end of 25 years.
What Happens To Old Solar Panels?
Solar panels are disposed of in different ways, depending on their location. EU laws state that manufacturers must ensure their products follow a proper recycling process. And nations such as India, Japan, and Australia are working on similar restrictions.
However, there are no solar recycling mandates whatsoever in the USA (except a state law in Washington). A limited number of independent solar panel recyclers exist to address this concern. Still, only an estimated 10% of US solar panels make it to these organizations. The remaining 90% of solar panel waste goes directly to landfills or is shipped off to other countries.
One of the primary concerns with this action is that developing nations don’t have the tools or equipment to deal with this level of toxic waste. There is low-quality control overseas, and many developing countries are happy to purchase second-hand solar panels that are substandard products.
A 2015 report carried out by the United Nations Environment Program stated that anywhere between 60% and 90% of electronics waste is illegally traded or dumped into developing nations. This places them at greater risk of suffering the consequences of solar waste.
In Ghana and India, people living near an e-waste dump will often burn this electronic waste to retrieve the valuable metals inside (i.e., the copper wires). But, this process involves burning plastic, which produces toxic fumes; when inhaled, these fumes are carcinogenic and teratogenic.
Can Old Solar Panels Be Reused Or Resold?
While IRENA’s e-waste projections are intimidating, the organization also highlights the possibility of repurposing these end of life panels to utilize the 78 million tons worth of raw materials – the value of which could exceed $15 billion.
The problem is that standard recycling processes aren’t sufficient where used solar panels are concerned, and recovering valuable materials such as silver and silicone requires bespoke recycling solutions. On the other hand, setting up these practices could create jobs and provide raw materials.
By 2030 alone, over $450 million worth of raw materials have the potential for recovery from decommissioned solar panels – enough value to create around 60 million new panels. Not only would recycling solar panels capture the raw materials value, but it would also save valuable space in landfills.
One way to stop solar panels from going to landfills is to reuse or refurbish them, though this market is yet to gain traction in the USA. Plus, additional factors such as fire, electrical, and building regulations need to be taken into consideration before reuse is possible.
Once panels are recertified, reselling them can help offset the cost of solar panel recycling.
How Do You Recycle Solar Panels?
Many elements of a solar panel can easily be recycled. Most are around 75% glass; plus, the aluminum frame, copper, and plastic are easy to recycle. Other components and valuable materials are more difficult to retrieve, such as silver.
The difficulty in the recycling process for the glass lies in the fact that all the constituent materials such as plastics, cadmium, lead, and antimony leach into the glass, making it impure. And this restricts its ability to be reused.
To recycle solar panels, a typical e waste facility removes the panel frame and the junction box, allowing recovery of copper and aluminum. The rest of the module is shredded, making an impure glass mixture composed of polymers, silicon cells, and silver electrodes.
Solar panels generally fall into one of two categories; silicon-based or thin-film-based. You can recycle both types of panels, but they each require a different process.
Want to lean more about the solar panel recycling process? click here for our article explaining it in detail.
How Are Silicon-Based Solar Panels Recycled?
When recycling silicon panels, the first step is to disassemble the product to separate the glass and aluminum. Heat or chemical treatments are commonly used, after which, around 95% of the glass can be reused.
You take the remaining materials to a thermal processing unit, where they are treated at temperatures of up to 500 degrees celsius. These high temperatures allow the plastic to evaporate, which leaves behind the silicon cells.
Acid then etches away these cells, and up to 85% of the silicon material can be repurposed or recycled.
How Do You Recycle Thin-Film-Based Solar Panels?
Thin-film-based panels require a more elaborate recycling process. Firstly, you shred these panels, then place them into a hammermill that ensures the maximum size of your particles is five millimeters.
At this size, the lamination breaks, and the materials inside become free. Your leftover product is a mixture of solid and liquid, which you can then separate with a rotating screw.
A precipitation process ensures the purity of the liquid solution while the metals are processed to separate their component parts. On average, you can reuse up to 95% of the semiconductor material.
A vibration process helps remove the interlayer materials for the solid mass, leaving you with pure glass. You can then repurpose up to 90% of these glass elements.
Why Do So Many Solar Panels Go To Landfill?
As always, money is a consideration for most solar manufacturers, and the cost of recycling is a lot higher than the cost of taking a panel to a landfill. The average price for recycling is between $12 and $25 (and that doesn’t include transportation costs), but a standard panel only returns around $3 in copper, glass, and aluminum. In contrast, taking a panel to a landfill costs around $1.
In the current environment, the cost far outweighs the revenue, and at around a 10 to 1 ratio, there is not much incentive for people to process their panels for recycling. One way of overcoming this would be to find a suitable procedure to separate the most valuable materials such as silver and silicon, making the process more economically viable for recycling companies.
Initially, Recycle PV Solar used a heating process that could recapture up to 90% of the panel’s materials. Still, recent research has found that European technology allows for a recapture as high as 95%. Separating the recaptured materials more efficiently would improve the cost-revenue ratio and provide a greater incentive for manufacturers to recycle their panels.
Do Solar Panels Contain Plastic?
Until recently, plastics have been a secondary component of a solar panel used primarily to connect electrical insulators, pipes, thrust washers, and valves, among other fittings.
In addition, manufacturers use plastic sheets to protect the silicon and glass panels and reduce the humidity inside the product.
However, recent developments mean that plastic is used more and more in the manufacture of solar panels. Creators are developing plastic solar cells to serve as PV material rather than silicon and glass. The reasons for this are cost reduction and durability.
Several types of plastic are commonly used in the production of solar panels. Acrylonitrile Butadiene Styrene or ABS is a sturdy plastic used to make the braces and attachments of the solar panel.
Acrylic or plexiglass provides a protective film to enhance a panel’s durability while reducing the level of internal humidity.
Polycarbonate is effective glazing to protect fragile elements within the panel. At the same time, polypropylene can be crafted into a base material for solar cells.
While many view plastic as a “bad” product for the planet’s sustainability, it is actually an essential innovation in renewable energy sources. Not only does plastic help to reduce the cost of a product, but it also decreases the environmental impact during production.
There are already issues around solar panel recycling, and solar panel disposal, a problem that will increase rapidly as the sale of solar panels did 20 years ago. The solar recycling industry needs fast change to avoid a solar e waste glut.
Not only this, but the production of these panels currently emits dangerously high levels of NF3 and other greenhouse gases.
With solar power an integral part of a cleaner, greener future for the earth, it’s essential that we find a way around these issues and reduce the solar waste and environmental impacts we are currently facing.