Unlike fossil fuels, solar panels emit no carbon dioxide (CO2) into the atmosphere while generating electricity. However, they do have some negative effects on the environment, which are associated with manufacturing, maintenance, and recycling. This article provides a description of said effects, and compares them to those of coal and natural gas.
Credit: Tom Fisk, PexelsThe creation of almost all panels begins with the mining of silicon, which is highly reactive, meaning it readily forms compounds with other elements. Therefore, ore containing silicon must go through an energy intensive purification process before use. This purification process is carried out in arc furnaces, which use the heat from an electrical arc between two carbon electrodes to melt their contents. The fact that arc furnaces are electrically powered means that as the grid becomes increasingly powered by renewables, solar’s production process will become far greener than it is today.
After processing, silicon is combined with metals such as aluminum, gallium, indium, lead, and cadmium, and covered with glass or plexiglass, to create functional panels. Following transportation and installation, these panels enjoy a long lifespan of 25-30 years. Once this amount of time has elapsed, the amount of energy they produce begins to decline, and replacement will eventually become necessary.
While the individual components of panels are not inherently difficult to recycle, the process of separating them from one another can be somewhat tricky. But several companies in Europe and the U.S. have risen to the challenge in developing reasonably effective techniques for recycling the solar panels and their constituent parts. As more innovation takes place in the field of solar recycling, the efficiency of this process will rise even further, and its environmental costs will fall even lower.
Any negative effects that solar panels have on the environment during their functional years are either minimal (in the case of solar farms) or non-existent (in the case of rooftop solar). Although the installation of large scale solar farms in natural habitats will understandably alter the land directly underneath the panels, they can be sited in deserts, or areas in which land has already been degraded, to minimize detrimental effects on the environment.
When compared to coal and natural gas, solar is the clear winner in terms of environmental impact. The best statistic to illustrate this fact is the amount of CO2 each respective energy generation strategy releases into the atmosphere, per kilowatt of energy generated. The Union of Concerned Scientists (UCS) website estimates this ratio to be between 0.07 and 0.18 (pounds of CO2 per kilowatt) for solar, between 0.6 and 2.0 for natural gas, and between 1.4 and 3.6 for coal. And again, these ratios will continue to improve for solar, as the energy used to process silicon comes increasingly from renewable sources. It is also worth bearing in mind the fact that the burning of coal releases many toxic compounds in addition to CO2 that can have significant negative effects on public health and the environment.
There are many ways we can help accelerate the world’s transition to solar energy. One obvious way is by installing solar panels on your house, and/or encouraging your friends to install panels on theirs. The energysage.com website is useful for determining how much money you could save by installing rooftop solar. For those of you looking to recycle old panels, check out the websites of the solar recyclers like U.S.-based Recycle PV and France’s Veolia.
Almost as good as going solar is spreading the word so more and more people are aware of the significant benefits and shrinking cost premiums of making the switch away from fossil fuels. The more of us are talking about it, the more our leaders and policymakers will listen and enact rules and legislation that go beyond encouraging renewable energy to mandating it.