The Looming Problem of Mass Disposal of Photovoltaic Panels with a Lifetime of 20 to 30 Years: Will the Urgent Need for Recycling Technology be Solved in Time?

The “mass disposal problem” of used panels has become an urgent issue…

Photovoltaic panels can now be seen everywhere: in fallow fields in farming villages, on vacant lots in mountainous areas, and on the roofs and yards of houses. The government is promoting the introduction of renewable energy, and the installation of panels has been expanding rapidly since the beginning of the ’10s.

The lifespan of photovoltaic panels is estimated to be about 20 to 30 years, and they are often “buried” as industrial waste at the end of their life. Those broken by typhoons and other natural disasters also become waste. While the disposal of panels will increase in the future, it is predicted that there will be a shortage of disposal sites to bury them.’ Some estimates suggest that 800,000 tons of used panels, or about 40 million panels per year, will be disposed of in FY40. The problem of disposing of large quantities of used panels has become an urgent issue.

Solar panels sometimes contain “toxic substances” such as lead and arsenic. According to the Ministry of Internal Affairs and Communications’ ’17 According to a survey conducted in 2005 by the Ministry of Internal Affairs and Communications, there were cases of solar panels being buried in landfills without water interception facilities without having been verified as containing hazardous substances.

Ministry of Internal Affairs and Communications (MIC) says, “It is difficult to grasp the total amount, and we have not been able to grasp all of it.”

Following this survey by the Ministry of Internal Affairs and Communications, the Ministry of the Environment’s Recycling Promotion Office says that “awareness is increasing” of the measures and responses that have been taken based on shared information. However, since panels are a mixture of glass, metal, and other materials, “it is difficult to ascertain the total amount of panels as a whole,” under the Waste Disposal and Public Cleansing Law, which attempts to ascertain the amount of glass and other materials as individual items, “so we are not able to ascertain everything.

Since the total amount of used panel disposal is not known, it is difficult to determine how much is improperly disposed of or illegally dumped in the statistics. Once the panels are buried underground, it is impossible to know how they are being disposed of.

On the other hand, the damage caused by torrential rains is becoming more severe every year, and measures to combat global warming are becoming more urgent. In 2012, the Japanese government introduced a feed-in tariff system for renewable energy, under which electricity generated from solar and wind power is purchased for a fixed period of time and at a fixed price. This has triggered a steady increase in the installation of photovoltaic panels.

Photovoltaic panels are difficult to “disassemble and recycle

Photovoltaic panels are characterized by layers of electrodes and silicon that are strongly bonded together. It is difficult to disassemble and recycle these panels, so they had to be buried. Recently, several companies have introduced and are promoting a treatment method that separates the glass portion from the other metal portions.

However,

“The recycling of used panels into new panels has not yet been realized,” said a Ministry of the Environment official.

This is what is called “horizontal recycling. Currently, for example, if it is a glass part, it is crushed into glass material and used, so-called “downcycling.

30 years from now Expanding to a 4-trillion-yen market in 30 years

However, recently, a case has emerged in which a basic technology has been successfully developed to realize horizontal recycling, and Takahisa Fujii, president of the PV Reborn Association (Nishiawakura Village, Okayama Prefecture), says, “We are in the initial stage. He is enthusiastic about further technological development to solve the cost problem and mass-produce equipment capable of horizontal recycling starting in 2008.

Currently, the cost per used panel is about 3,500 yen. The cost per used panel will be around 3,500 yen. In 2025, the cost per used panel will be about 270 million yen. In 2008, the company processed approximately 270 million panels. million panels were processed in 2008, so there was a panel processing market of about 945 billion yen. It is estimated that there was a panel processing market of about ¥945 billion. In the year 2020, the market is expected to grow to four or five times this size. In 2010, the market is expected to be four to five times this size, growing to a market of 4 trillion yen. If these panels are transformed into new panels through the realization of horizontal recycling, it may be possible to eliminate the need to import raw materials for panels and the products themselves from China and other countries.

The horizontal recycling technology being developed by the PV Reborn Association and others looks like this. For used panels with aluminum frames removed, the strong adhesive parts are separated into glass, solar cells, and copper wires in a pyrolysis treatment furnace using superheated steam at 600°C or higher. The encapsulant and other materials are vaporized by the heat. In this way, the used panels are said to be broken down to raw materials and transformed into recycled panels.

Many of today’s solar panels are made in China.

Mr. Fujii of the PV Reborn Association says, “Our goal is to obtain used panels, disassemble them, return them to raw materials, and lower the cost of manufacturing new products so that they are cheaper than Chinese products.”

Reducing processing costs is a major issue for the future, he said.

The treatment facility under development will be something that small and medium-sized companies with a certain degree of technical capability can install, Fujii says. If the system spreads throughout Japan, it may solve the problem of mass disposal of used panels.

An official from the Ministry of the Environment says that even at present, “the cost of disposal is troubling. Even if a processing facility is set up, the cost of transporting the used panels to the facility is prohibitive. In some areas, it is cheaper to shred the panels and dispose of them in landfills.

If horizontal recycling facilities for used panels could be established throughout Japan, the problem of mass disposal, including the cost of transporting the panels, could be solved at once, and hopes are high that the technology could be put to practical use in a few years, as the PV Reborn Association is planning to do.