The Life Cycle of a Solar Project
With conversations of climate change and decarbonization increasing globally, solar is brought up often as a convenient and green alternative to fossil fuels for powering the grid. According to the 2021 Solar Futures Study by the United States Department of Energy, solar has the potential to provide up to 40% of the country’s electricity production by 2035 and up to 45% by 2050. Solar is clearly on the upswing as a renewable power source, but the process takes time. The project life cycle starts with a piece of land and an idea. After years of development and decades of energy production, the vast majority of the solar facility can be recycled.
After a solar panel is no longer considered useful, there are usually two ways to deal with them – throw them away or recycle them. In the United States and Europe, solar panels are considered e-waste and must be dealt with accordingly. According to Attila Tamas Vekony in a 2021 GreenMatch article, while there are no US federal guidelines, the European Union has mandated that developers and owners of solar projects must incorporate the cost of recycling panels into the cost of the project so as to not place additional burden on the environment. Washington state is the only US state to have a similar mandate.
If it were not for recycling, GreenMatch lists that up to 60 million tons of solar panel waste could accumulate by the year 2050, which is why recycling them is so important. Because most solar panels are made from one of two materials, there are two different recycling processes: silicon-based panel recycling and thin-film based panel recycling.
Silicon based panels are the most commonly used panels that we have today. The process begins by separating the panel’s aluminum and glass parts. “Almost all (95%) of the glass can be reused, while all external metal parts are used for re-molding cell frames,” says Vekony at GreenMatch. In addition, a significant portion of the hardware (80%) can be reused after the initial recycling treatments. The silicon parts are also able to be recycled and reused. Often, all the pieces of old solar panels can be recreated into new solar panels.
Thin-film based solar panels are less common and require more processing to be reused and recycled. After being shredded and crushed into tiny pieces, both liquid and solid materials are leftover to be processed. “Liquids go through a precipitation and dewatering process to ensure purity. The resulting substance goes through metal processing to completely separate the different semiconductor materials. The latter step depends on the actual technology used when producing the panels; however, on average 95% of the semiconductor material is reused,” according to Vekony at GreenMatch. After that, there is solid matter to be further processed which leaves behind pure glass that is recycled easily.
What starts out as a piece of land and a plan to decrease our carbon footprint turns into a project that generates clean energy for 20-25 years or more and solar panels that can be recycled into new solar panels. There are lots of moving pieces, but solar is one of the simpler renewable technologies to install which makes it a prime candidate for potentially powering up to 40% of the United States grid in the near future.