The energy sources we use have their history rooted in the sun5: coal, oil, natural gas, and wood. Today, science promises us green energy harvested from the sun using solar panels. But what makes solar energy green?
Global energy consumption is rising. By the middle of our century, scientists predict that our energy needs will have doubled. About 80% of global electric power comes from fossil fuels - usually from burning petroleum, coal, oil, and natural gas.
The negative impact of using these fossil fuels on our environment is broad. First off, energy producers extract this fuel from below ground level, which requires mining and drilling.
This process often results in contamination of water bodies. Pollution is common. Further, the refinement process also releases toxic gases1, known as greenhouse gases, into the environment. The presence of these gases in our atmosphere contributes to what we know today as climate change.
We must also consider transportation costs. Further emissions can be added due to energy burnt transporting these fuels to consumers. This happens across the globe.
Of course, as end consumers, we burn fossil fuels. Providing energy to our homes, cars, and factories also produces greenhouse gas emissions, as does burning fossil fuels to generate electricity used in the home.
More Reading: Advantages and Disadvantages of Solar Energy
With this in mind, scientists and engineers are constantly trying to improve the use of different types of renewable energy. To do so, they're implementing new ways to harvest clean (and, if possible) renewable energy.
Some renewable energy sources that have gained traction are wind energy, solar energy, hydropower, and biomass. These sustainable alternatives will prove crucial for our future energy needs while battling climate change.
Solar energy stands out in particular, and for a good reason. It is clean, which means that its production and consumption have a less negative impact on the environment. It is also renewable; as long as the sun burns, we can always harvest energy from it.
Finally, solar energy is free to use. If you have the right infrastructure, households can generate solar energy. So too can large energy companies. We can even work to convince schools to adopt solar energy. To understand what makes solar energy green, we should look at how we produce it.
Solar energy is possible through a process called photovoltaic transformation4. When sunlight hits the solar panels, it initiates this process. This process involves converting light into energy at an atomic level. Some materials exhibit a photoelectric effect, such as silicon, which makes it an excellent option for this conversion.
They make solar panels from monocrystalline or polycrystalline silicon. When sunlight hits the outer layer of the silicon, it knocks free electrons. Silicon is typically exposed through a glass casing. These freed electrons provide the basis needed for generating electricity.
The process creates an electric current held and transmitted by the wiring within the solar panel.
The amount of energy generated depends on how much sun exposure the solar panels are getting. Therefore, solar panels are installed in shade-free areas such as the roof of a building. Or in open fields with no trees or buildings. Generally, the more exposure to the sun, the more potential energy generated by solar panels increases.
Now we have the basic idea of how they generate solar energy. It is easy to see what makes solar energy green.
Further Reading: How is Solar Energy Produced?
From the description of the solar energy production process, we can see how solar energy interacts with the environment. The lack of any of the harmful outputs of fossil fuel production means that solar energy production is green. The following are the important things to note.
The production and consumption process of solar energy does not cause any carbon emissions. Solar panels used for power generation do not cause air pollution associated with coal-fired power plants and burning other non-renewable sources. Unlike fossil fuels, they are considered safe for use everywhere, including around the home.
Solar panels will continue to generate energy from sun contact. Of course, this is as long as we keep them functional. Most panels have 30 years of useful life. And the sun is a renewable energy source. As such, solar farms and at-home installations will continue to provide electrical energy indefinitely.
Transportation contributes about 29% of the greenhouse gas emissions every year. These emissions are a result of burning fossil fuels like gasoline and diesel. Energy companies and retailers burn fuel in transporting oil to refineries.
Transporting the refined fuel to countless gas stations across the globe burns even more. The one-time process of transporting solar panels to their places of installation consumes energy. Beyond this, users never have to burn fossil fuels while transporting solar energy.
This article would not be objective if we did not highlight the negative impact of solar panel production. If we ask, "is solar energy green?" then data from decades of research provides us with the short answer "yes." However, the overall impact of solar energy does not just start from the minute we plug in our solar panels.
Cathy Chen of Global Shapers puts it this way: "Solar energy is green. Solar panels are not."
Every solar panel manufactured, sadly, leaves a carbon footprint. The conversion of the silicon used in photovoltaic panels into monocrystalline or polycrystalline silicon requires a lot of energy. Scientists place the ballpark amount at 2000°C.
Further, this production process is so energy-intensive that it still requires fossil fuel. According to Cathy Chen, most producers of these products are located in less developed regions. Of course, these regions often have lower environmental standards.
The production process also involves the use of chemicals6. These include hydrochloric acid, nitric acid, sulfuric acid, hydrogen fluoride, acetone, and 1,1,1-trichloroethane. Without proper control, workers could face significant health risks.
Also, solar panels are not easy to recycle2. In fact, the disposal of solar panels has become an issue of significant concern. Naturally, recycling solar panels costs time and money.
Solar companies are taking care of this by offering recycling benefits. Users are encouraged to dispose of their solar panels properly, so they do not end up in landfills.
In some regions like the EU, the government considers solar waste as e-waste. This is a policy included in the Waste Electronic and Electrical Directive3. Therefore, manufacturers are bound by law to provide recycling options to prevent a solar panel waste problem.
Much talk is still ongoing concerning the effect of solar panel production on the environment. Therefore, science must seek to reduce or totally eradicate these impacts.
Earlier this year, researchers revealed that they had launched a new project to improve this situation. The project uses AI to develop new solar panel designs and materials. As a result, researchers believe they can improve the environmental impact of solar panel production.
Solar energy is not only renewable, but it is also available planet-wide. Therefore many of the world's energy problems faced today can be reduced through increased investments in renewable energy generation from the sun. Each installation will help to grow renewable energy's positive impact on reducing climate change. This is especially true in third-world countries.
On the subject of being green, we can say that solar energy is green. However, there are obvious concerns about the impact on the environment of the production of solar panels.
Solar panels have a lifetime value of 30 years. As such, they will serve their users for at least that long when appropriately maintained. This is a better option when compared to fossil fuels. We produce fossil fuel for use quickly and exhaust the energy within a short time frame.
We expect that with the advancement in technology, a more environment-friendly approach to producing solar panels will emerge.
|1||V. Ramanathan, Y. Feng, Air pollution, greenhouse gases and climate change: Global and regional perspectives, Atmospheric Environment, Volume 43, Issue 1, 2009, Pages 37-50, ISSN 1352-2310, https://doi.org/10.1016/j.atmosenv.2008.09.063|
|2||Choi, Jun-Ki & Fthenakis, Vasilis. (2010). Economic Feasibility of Recycling Photovoltaic Modules: Survey and Model. Journal of Industrial Ecology. 14. 10.1111/j.1530-9290.2010.00289.x.|
|3||European Commission: Waste Electrical & Electronic Equipment (WEEE)|
|4||A. Stoppato, Life cycle assessment of photovoltaic electricity generation, Energy, Volume 33, Issue 2, 2008, Pages 224-232, ISSN 0360-5442, https://doi.org/10.1016/j.energy.2007.11.012.|
|5||L. Szabó, "The history of using solar energy," 2017 International Conference on Modern Power Systems (MPS), Cluj-Napoca, 2017, pp. 1-8. doi: 10.1109/MPS.2017.7974451|
|6||S. Ranjan, S. Balaji, Rocco A. Panella, B. Erik Ydstie, Silicon solar cell production, Computers & Chemical Engineering, Volume 35, Issue 8, 2011, Pages 1439-1453, ISSN 0098-1354, https://doi.org/10.1016/j.compchemeng.2011.04.017.|