Recently, the US and Australia signed and announced a “Net zero technology acceleration partnership” asserting a breakaway from Chinese dominance: “We’ve seen what happens when we rely too much on one entity for our source of fuel, and we don’t want that to happen – so to diversify those energy sources and to link up with partners is part of our energy security.”
Walking aloof from the world of fossils with the help of renewables (prominently Solar), it was believed that the tropical, naturally blessed yet struggling nations of the tropics will benefit most.
However, ever-evolving technology change in Solar has helped Chinese to extend the scope of their comparatively cheaper solar panels in every nook and corner of the world.
It all started as an attempt to reduce Chinese dependence on foreign energy in the late 2000s.
It is believed that Chinese manufacturers are responsible for the supply of nearly 80 percent solar panels currently with the largest investments in renewable energy, flowing within the country and outbound and will soon be able to manufacture as well as supply up to the world’s 95 percent by 2030, according to a recent IEA’s report.
Renewable too, seems to be a little opportunistic for a selected few.
And hence, 6 million metric tonnes (mmt) of predicted new solar waste will get generated annually because of the premature disposal of panels (reasons: increased efficiency, reduced cost).
But have we ever wondered what happens to a solar panel once outdated? Do they find their lost value anyways?
Dead Solar Panels: spreading light even in the afterlife
As per IEA’s report, solar power installations have risen by over 30 percent annually on average in the last decade and they can continue to function for decades (25-30 years efficient output from the panel) if they are kept clean and maintained. But what happens to these panels once they grow old?
It is assumed that after being decommissioned, these panels are doomed to rest in landfills with worse consequences. Why? Because it takes approximately $15–$45 to recycle the module while it takes only $1–$5 to dump it.
It is not just the waste that’s harmful but heavy metals from batteries like lead or cadmium seep inside the ground and consequently damage soil productivity, kill plants and ultimately impact food chain causing health problems in humankind.
While the solar recycling facilities operating at certain places choose to extract precious minerals like silver or copper from these, they end up burning contaminated glasses etc., and polluting the very fragile environment it was anticipated to cleanse.
Disposal of solar panel waste:
“The problem with end-of-life modules is that they were not intended to be dismantled, and that’s a major drawback”, explains an Industry expert.
One can only understand the gravity of the situation with clarity in a panel’s structure. Though there are multiple models of silicon PV panels available in the market, they usually have similar designs.
These energy cells are composed of a sandwich of silicon, aluminium and silver wires, which are further tied into modules by copper wires fused with lead and tin.
This package is then bound in layers of glue-like polyethylene-co-vinyl acetate (EVA), black-colored polyethylene terephthalate (PET) and polyvinyl fluoride (PVF), which is further covered with glass sheet and encapsulated with an aluminium frame.
Bulk components like glass or aluminium make up more than 80 percent of the PV’s mass but only one-third of its monetary value while silver, silicon, copper and others make up two-thirds.
Still, it is interesting to note that the share of solar PVs in generating electricity may be close to 3 percent globally but it consumes huge amounts of mineral and resources: 15 percent of world’s silver, 40 percent of the global tellurium and other proportions of quartz, zinc, gallium etc.
Where is the ultimate challenge?
The challenge lies in separating silver from the cell to retrieve an uncontaminated silicon wafer, i.e., a quest for better material management.
Solar Waste, unfortunately, falls under the electronic waste category and is resold as scrap in the country. This waste finds no mention in the electronic waste management regulations 2016.
However, as per the Ministry for New and Renewable Energy (MNRE), a committee has already been constituted with the Ministry’s Secretary as its Chairman to derive an action plan for “circular economy” in solar panel world by reusing and recycling of waste.
Although the solar cell manufacturers find it mandatory to accomplish certain legal specifications and standards to be least hurtful to the environment.
The revolutionary disassembly:
It is not that the world and India does not have the technology to dismantle a panel safely and there is constant evolution in the same yet simply unsticking a module’s glass away from its cells is a tedious task. Are there ways to lessen this difficulty?
This can be achieved using organic solvents in place of glue to eliminate EVA, but this is a costly practice as well as it generates ample hazardous waste.
One can use infrared heaters paired with a vibrating knife to cut a panel’s glass and separate it. Once this is done, precious materials beneath can then be extracted leaving a pure 200 µm wide silicon wafer behind, producing which consumes nearly half of the energy used in making a solar module. This can also reduce the current carbon footprint of the PV trend.
Though the PV recycling is known to have the potential to create significant numbers of green jobs, it can also garner nearly £11 billion as recoverable value (of Solar infrastructure recycled) by 2050 which can additionally produce 2 billion new panels and around 630 GW of energy.
An expert from solar recycling claims: “Even if we were to only focus on the top four constituents in mass composition and value—aluminium frame, glass, silicon, and silver—you wouldn’t have that much left to bury. I’m not calling for that, but you would be taking care of well over 90% of the mass of your modules. And that’s a heck of a lot better than burying the whole thing.”
Also, it is not just the dead solar panels adding up to the waste, there are cases of these being damaged or discarded during transportation, installation or plant operations.
According to an analysis by CEEW, PV modules have so far generated a possible waste of 285,000 tonnes till 2021, just from the installed capacity of 40 GW grid-connected solar infrastructure.
It has been estimated that the current global value of this recoverable material can exceed USD 15 billion. One can think how can India leverage its 325 kilotonnes of solar waste to be produced by 2030.
Besides the technological improvements, policy regulations and innovative business models often play a critical role in accelerating PV recycling across the globe.