Solar Panel Recycling
Solar Panels Harm Our Planet--In Ironic Ways
Alternative-energy enthusiasts use and recommend solar panels not only because they generate cleaner and more efficient electricity but because they do so with minimal strain on the environment. But solar panels are better and not perfect solutions to our climate problems.
The universe is essentially a closed system. This means that energy is never created but converted. Solar energy works in no different ways. Besides free, harmless and abundant sunlight, there are environmental loses incurred in the process of generating electricity from solar panels. The loss of land space that could be used for agricultural purpose especially in large-scale installations puts strains on the environment. Solar cells are made from silicon. Silicon is found in abundance in nature as quartz sand. Purifying quartz sand into pure usable silicon consumes tremendous amounts of energy. Ironically, much of this energy used in manufacturing solar panels is generated from plants powered by fossil fuel!
To purify silicon, quartz sand is heated with the climate's worst nightmare, coal. This conversion process otherwise called Carbon Arc Welding involves placing the sand mixed with carbon into an electric arc furnace and heating it to temperatures beyond 2,000°C. To reach those high temperatures would require insanely high amounts of coal. The goal is to remove the oxygen from the silicon dioxide by burning it off to give carbon dioxide and pure silicon. (According to Sinovoltaics, approximately 11 tons of coal is burnt to make one solar panel! To produce 1 billion square metres of solar panels would require 2,000 million metric tonnes of coal!) The final product of the process is molten silicon and large amounts of carbon dioxide and other harmful greenhouse gases that accelerate global warming released into the atmosphere. This is besides other harmful liquid and solid by-products.
The purified silicon account for just 5% of the chemical component of the solar panel. The glass cast accounts for up to 75% of the weight of solar panels and it is made in a similar process as the silicon cells--by heating silicon to temperatures above 1,500 degrees in furnaces! Moreover, small amounts of what is considered very dangerous to both the environment and health of living organisms, lead and tin, is used in making solar panels. (The use of lead in the manufacture of solar panels is highly controversial.)
Climate optimists who believe solar energy will solve all of mankind's climate problems are often unwilling to admit or respond to this uncomfortable truth. Nonetheless, the comforting thing about solar panels is not that it places no strains on the environment but that this strain is comparatively minimal. Fossil fuels are made from similar energy-intensive manufacturing processes. They double the strain they impose on the environment during their consumption. When in use, solar panels do not harm the environment in anyway. Except as unmanageable waste.
Recycling Solar Panels
Solar panels have a net lifetime of about 25 years. At the end of their lifetime, they are made to be disposed properly for recycling. At the growth speed of the industry, the amount of solar panel waste is expected to rise from 250 metric tonnes in 2016 to 80 million metric tonnes by 2050! The chemical elements that make up the weight of a typical solar panel include the following
About 75% glass
And small amounts of silver, tin, lead, and other metals and components.
Of the components listed above, aluminium, polymer backsheet and the copper that account for the frame and the terminal box parts of the panel, have well-known and efficient recycling processes and can be easily recycled. Though the other chemical components are 100% recoverable, including the glass and silicon, recovery rates seen in practice are still not high enough. Also, the products of the recycled products do not have competitive value when compared to manufactured ones. Existing recycling methods are still very expensive and energy-intensive and can be driven by only the necessity for proper waste management and not profit.
The manufacturing industry has optimized manufacturing processes to reduce their carbon footprints. Efforts are being made to optimize existing recycling processes and to develop more sophisticated ones with higher recovery rates. Though the second law of thermodynamics remains absolute over all chemical processes in the universe, the future is not bleak. The central challenge is for manufacturers is to make more efficient solar panels that can return higher output of electricity per surface area of the solar cells. This alone can mitigate the impact of the manufacturing processes on the environment. Much of the solar industry efforts are directed towards meeting this challenge.