Solar energy is no doubt one of the best forms of renewable energy we have to fight climate change. To capture solar energy, we need solar panels. But many people argue that the manufacturing of new solar panels and disposing of dead solar panels do more harm than good for the environment. So, is it worth it? To answer the question, I’m going to look at the energy needed to manufacture solar panels and analyze what percentage of the materials can be recycled so it doesn’t end up in landfills.
A functional solar panel is made up of many parts. They include a frame, tempered glass, encapsulant material such as EVA film, solar cells, a back sheet, and a junction box.
The most important part of any solar panels are the solar cells. Solar cells convert sunlight into electricity through photovoltaic effect. Photovoltaic effect is the process of knocking electrons from one semiconductor layer to another with the help of photons (light). This generates a flow, which we call electrical current. Solar cells are commonly made from silicon, a semiconductor
that is one of the most abundant elements on Earth. Many solar cells are grouped together to form a solar panel. The metal frame of the solar panel is typically made of aluminum, which is also abundant on Earth. The frame holds all the layers together and protects the edges. It also helps mount the solar panel onto a desired location. The tempered glass is the top layer of the solar panel, and it plays a critical role. The glass protects the sensitive cells from rough weather and allows solar light to reach solar cells. The encapsulant material such as EVA film adds another layer of protection for the solar cells. They sandwich the solar cells, so they are protected from UV rays and other environmental factors. The back sheet is the last layer of the solar panel. It can be made with many materials including PP, PVF and PET. It acts as a moisture barrier and as well as an insulant. The junction box, which is attached to the back sheet, is a waterproof box that works as a central point where wires connect to diodes, providing an easier way to connect the panels together.
According to the Union of Concerned Scientists, solar is one of the lowest CO2 emitters per kilowatt-hour when compared to other sources such as natural gas and coal. Solar releases between 0.07 to 0.2 pounds of CO2, whereas natural gas releases 0.6 to 2 pounds and coal 1.4 to 3.6 pounds.
Solar also has the incredible ability to produce net gain energy over its lifetime. A basic multicrystalline silicon module requires about 420 kWh electricity to produce, which could be paid off within 4 years of usage. Assuming solar modules lasts for 30-years, there is a net gain of 26 years of free energy.
There are many great things about solar panels, including their low CO2 emission and years of pollution-free energy. We also have to consider the environmental factors related to the disposing of dead solar panels. Will solar panels fill up the landfills? The great thing about the materials used to manufacture solar panels is that most of them are recyclable. For example, 100 percent of the aluminum frame, and 95 percent of the glass is recyclable. Heating and evaporating the encapsulant film will expose the silicon, 85 percent of which can be recycled. The recycled materials could then be used to make new panels. There is also a small percentage of heavy metals and toxic waste in solar panels, but scientists are actively working to find a solution.
To conclude there are both pros and cons to solar panels, but if you look at the big picture, the benefits significantly outweigh the negatives.