Why Are Solar Panels Good For The Environment?
Solar energy is one of the fastest growing energy sources thanks to net-zero emission targets and rapidly improving technology. As the world increasingly prioritises clean energy, it is important to question are solar panels actually good for the environment? Or are they are just a quick solution to meet targets?
Solar panels are considered to be a clean energy source as they don't generate carbon emissions during operation. They do, however, generate carbon emissions during manufacturing and decommissioning, and there are concerns about their waste management and recycling.
Despite this, solar panels produce only 41 grams of CO2 equivalent emissions per kWh of electricity generated across its entire lifecycle, which is still around 25 times less than the emissions produced from burning coal. It is therefore an easy answer. Solar panels are good for the environment.
What's more, with current solar cell research, their outlook is still improving.
Solar Panels And The Environment: Advantages vs. Disadvantages
Environmental Benefits of Solar Panels | Environmental Drawbacks with Solar Panels |
Reduces grid dependency resulting in less fossil fuels being burned. | Produces waste at the end of their lifespan which is difficult to recycle. |
Don't produce greenhouse gases during operation. | Manufacturing process produces some carbon emissions. |
Don't rely on a finite energy source. | Often paired with batteries to store energy but these are difficult to produce and dispose of sustainably. |
Have a long lifespan with no operational costs. | Can require large amounts of land to install. |
Don't require water for cooling unlike fossil fuels. | |
Can provide agricultural benefits. |
As this table shows, the environmental benefits of solar panels definitely outweigh the drawbacks. Even with these issues, solar panels are a far cleaner energy source than fossil fuels.
Even considering this, there is still plenty of research into solar panel technology to make them easier to recycle, achieve a more consistent power output and to streamline their manufacturing process.
Environmental Benefits of Solar Panels
Despite their limitations, solar panels are still one of our best tools against climate change. Fossil fuels such as coal and oil are finite and rapidly depleting. In contrast, solar energy is readily available in massive quantities all around the world.
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Solar Panels Reduce Dependency on Fossil Fuels
People who have solar panels installed on their homes depend less on grid-generated energy. This reduced demand means less fossil fuel will be burned. Ideally, the energy demand from the grid can be fulfilled with renewable energy sources.
If energy demand from the grid decreases, there will be less need to use fossil fuels to make up the supply and existing renewable sources can be used instead.
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No Greenhouse Gases or Pollution
Solar panels do not produce pollution during their operation. Burning fossil fuels produces greenhouse gases such as CO2 which trap heat in the atmosphere, leading to global warming. They also release particulates into the air when burnt which can cause smog. Living in areas with smog reduces both life expectancy and quality of life due to the damage caused to our lungs when breathing it in. Solar panels do not produce greenhouse gases or smog whilst they generate energy, making them suitable for installation near populated areas.
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Truly Renewable Energy Source
Solar panels gain their energy from the sun. This is a free and abundant resource - unlike fossil fuels which are finite and therefore expensive. The more we are able to rely on renewable energy sources like solar power, the the better both for the environment and for decreasing the cost of energy globally.
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Long Lifetime and Are Low Maintenance
Once a solar panel has been installed, it will continue to generate electricity for several years with no operational costs and very little maintenance. Their lack of moving parts means that all they need is a quick clean every now and then to maintain their energy output.
Additionally, solar panels also do not require water to keep them cool. Many other energy-generating systems such as coal burning plants and nuclear power plants require massive amounts of water to keep the systems cool. Solar panels do not need this meaning they can be installed anywhere, even if access to water is limited.
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Compatible With Farming
Solar farms require a large amount of land to setup which could be seen as a negative environmental impact. It is often argued that this land usage is not only disruptive to native wildlife and ecosystems, but also wasteful. The land taken up by solar farms could be used for other things, such as by farmers to grow crops.
In reality, solar panels do not pose an issue to farmers and can actually be very beneficial:
- Land potential: Solar farms are typically built on land that is not suitable for farming, making use of otherwise unusable space.
- Agrivoltaics: A new industry is developing which enables food crops to be grown between rows of solar panels. This has proven to increase biodiversity as the crops are largely free from human interference. Some plants such as leafy greens also benefit from the shade provided by solar panels, and the shade also reduces the amount of water needed during the growing process.
- Livestock grazing: Installing solar panels on land used for livestock grazing has been shown to improve forage quality and reduce water demand. Additionally, sheep that live in fields that have solar panels installed live healthier lives. Their food is better quality, they are able to graze more, and tend to rest more in the shade that the solar panels provide.
Environmental Drawbacks of Solar Panels
Despite their many environmental benefits, solar panels do still have some drawbacks. It is important to acknowledge these because it helps to guide future research and development.
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Difficult Disposal and Recycling
Solar panels have a lifespan of 25-30 years, and disposing of them is challenging.
Up until now, solar panel disposal has not been a significant issue. Commercial solar panels were first introduced in the late 1990s-early 2000s so we are only now starting to face the issue of their disposal. Solar panel waste is expected to increase from 50,000 tons in 2018 to over 60 million tons by 2050.
Solar panels can be recycled, but it is a complex and costly process. More research is required to improve recycling efficiencies, and more dedicated recycling facilities need to be built. Without this, solar panel waste will be directed to landfills.
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Energy Intensive Manufacturing Process
Most carbon emissions associated with solar panels arise during the manufacturing process.
Solar panels are mostly comprised of non-toxic materials such as silicon and glass, with small amounts of metals such as copper, silver, tellurium, and indium. Gathering silicon has a low environmental impact as it is abundant and non-toxic. The metals, on the other hand, pose a larger issue. They must be mined which is highly disruptive to local environments and can cause soil, water, and air pollution.
To make solar panels, large manufacturing facilities must be built which requires lots of space. The manufacturing process itself is energy intensive and has many steps. For example, purifying and crystallising silicon requires high temperatures, needing large amounts of energy – this energy likely comes from burning fossil fuels.
The carbon footprint of a solar panel is estimated to be around 41 grams of CO2 equivalent emissions per kWh of electricity generated . This accounts for the whole lifecycle of a solar panel – from mining its materials to disposal at the end of its life. Because solar panels do not produce carbon emissions whilst generating electricity, their carbon footprint is offset by clean energy production within three years of operation.
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Shipping Emissions
Shipping solar panels from manufacturers to installation sites adds to their carbon footprint. The current biggest manufacturer of solar panels is China – they produce around eight out of every ten solar panels. Expanding manufacturing globally can reduce these emissions.
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Solar Panels Are Often Installed with Batteries
Many solar panel systems are installed with batteries to store excess generated energy. This stored energy can be used when solar energy generation drops, e.g. at night.
Producing and recycling batteries raises other environmental concerns. Most batteries used to store solar energy contain toxic chemicals that are difficult to mine including lithium, lead, and cadmium.
Batteries used for solar panels have a lifespan of 5 to 15 years, meaning they will likely have to be replaced within the typical lifespan of a solar panel. Once a battery reaches the end of its lifespan, the harmful chemicals it contains must be disposed of in a safe way. If batteries are not correctly disposed of, they can cause damage to the surrounding environment.
The Future of Solar Panels
Solar panels produce some carbon emissions across their lifetime, but they still have a lower carbon footprint than many other energy generating sources. Their rise in popularity also means that there is a lot of interest in further reducing associated emissions.
For example, many countries are now introducing laws to make solar panel recycling mandatory. As a result, we are likely to see more dedicated solar panel recycling facilities arise in the future. Recovering more materials will result in a lower energy expenditure during the manufacturing phase and less waste going to landfill.
New materials are also being developed to create solar panels with higher efficiencies or with easier processing methods. For example, perovskite solar cells or organic photovoltaics are thin film photovoltaic (PV) devices that can be through solution processing methods. This is much cheaper and easier than the processing of current silicon-based PV cells.
These alternative solar panels are still in the research and development stage. They have the potential for high efficiencies but there is more work to be done improving their stability and environmental impacts. This involves using green solvents and eliminating the use of heavy metal components.
References
- Annex III: Technology-specific cost and performance parameters. In:..., Steffen Schlomer et al. (2014)
- Putting Solar Panels In Grazing Fields Is Good..., C. Leste-Lasserre, New Scientist. (2023)