Power generation is one of the fundamental pillars of modern society. With the increase in the world population and energy consumption, there is a need to explore and analyze energy sources that can meet these demands in an efficient and sustainable manner.
In this context, nuclear energy and fossil fuels (coal, oil and natural gas) are among the most relevant sources. Both have significant advantages and disadvantages, and each plays an important role in the global energy mix.
This comparative analysis aims to provide a clear overview of the characteristics, environmental impacts, costs and sustainability of these two energy sources.
1. Definition and operating principles
Nuclear power
Nuclear energy is obtained through nuclear reactions, mainly nuclear fission, in which the nuclei of heavy atoms, such as uranium-235, are split into smaller fragments, releasing a large amount of energy.
This energy is used to heat water, generate steam and drive turbines that produce electricity.
There are two forms of nuclear energy generation: fission, which is widely used today, and nuclear fusion, which is still in the experimental phase.
Fossil fuels
Fossil fuels are energy sources that come from the remains of living organisms that have been subjected to heat and pressure for millions of years.
The combustion of these fuels releases energy in the form of heat, which is then converted into electricity or used for transportation.
These types of fuels have been the basis of industrialization and economic development since the Industrial Revolution.
2. Environmental impact and carbon emissions
Nuclear power
One of the main advantages of nuclear energy is its low emission of greenhouse gases during the operation of nuclear plants.
Unlike fossil fuels, nuclear fission does not produce carbon dioxide (CO₂), a gas directly responsible for global warming. According to the Nuclear Forum , CO₂ emissions per kilowatt-hour (kWh) of energy produced at a nuclear plant are significantly lower than those from plants burning coal or natural gas (Nuclear Forum, 2021).
However, nuclear energy does present some environmental problems. The main one of these is the management of radioactive waste.
Nuclear waste, which can remain hazardous for thousands of years, requires safe, long-term storage. The storage of this waste remains a controversial issue, and a definitive solution has not yet been found for many countries, although there are facilities such as the Yucca Mountain waste repository in the United States that attempt to solve this problem.
Furthermore, the risk of nuclear accidents, although low, can have catastrophic consequences, as seen in the cases of Chernobyl in 1986 and Fukushima in 2011.
Fossil fuels
On the other hand, fossil fuels are responsible for a large part of CO₂ emissions globally.
According to the International Energy Agency (IEA) , 75% of greenhouse gas emissions come from the burning of fossil fuels (IEA, 2020). Burning coal, in particular, is the most carbon-intensive source, followed by oil and natural gas.
This contributes directly to climate change, which is making fossil fuels increasingly questionable as a long-term energy source.
In addition to CO₂ emissions, fossil fuel extraction can also have serious environmental impacts, such as air and water pollution, deforestation and biodiversity loss.
On the other hand, the exploitation of coal, gas and oil deposits can deeply affect local ecosystems, as has been observed in the Amazon region due to oil and gas extraction.
3. Production costs and efficiency
Nuclear power
The cost of nuclear power generation is one of the most debated aspects. Although the construction of a nuclear power plant involves a significant initial investment, which can exceed $6 billion in some cases, the long-term operating costs are relatively low.
Nuclear power plants have a lifespan of 40 to 60 years, and their operation and maintenance costs are not that high compared to other energy sources. In addition, nuclear energy conversion efficiency is high, meaning that a small amount of nuclear fuel can generate large amounts of energy.
However, the costs of decommissioning nuclear plants and managing radioactive waste can add considerable cost to the life cycle of nuclear plants.
Another aspect to consider is that the construction of new nuclear plants has been hampered by a lack of funding and complex safety regulations.
Fossil fuels
Fossil fuels, on the other hand, tend to be cheaper in terms of initial investment and have a well-established infrastructure.
Coal, gas or oil plants are relatively cheaper and faster to build than nuclear plants. The infrastructure for extracting, transporting and processing fossil fuels is also highly developed, allowing for an efficient supply chain.
However, operating costs of fossil fuel-fired plants can be volatile due to fluctuations in raw material prices.
For example, the price of oil and natural gas has experienced large fluctuations in recent decades.
Furthermore, public health costs related to air pollution and other environmental impacts are not always reflected in the price of fossil fuels, which can generate economic externalities.
4. Sustainability and future
Nuclear power
Nuclear energy has the potential to be a sustainable source of energy, especially when compared to fossil fuels, which are finite and will contribute to resource depletion in the coming decades.
Uranium, the most widely used fuel in nuclear fission, is abundant and, although it is not renewable, there are prospects for using other elements, such as thorium, which could extend the life of nuclear energy.
In addition, nuclear fusion research promises to revolutionize the energy sector, as fusion is expected to produce energy without the radioactive waste associated with fission. However, despite the advances, nuclear fusion is still in an experimental phase and is not ready to be an immediate solution.
Fossil fuels
Fossil fuels are a non-renewable source of energy. Coal, oil and natural gas are in the process of being depleted, posing a considerable challenge to long-term sustainability.
On the one hand, the extraction of these resources is also becoming more expensive and dangerous. On the other hand, efforts to find alternative sources of energy, such as renewable energy (solar, wind, hydroelectric), are becoming more important, since these sources are practically inexhaustible and much more sustainable.
The shift to a low-carbon economy is a global goal, driven by agreements such as the Paris Agreement on climate change.
To meet climate goals, a drastic reduction in the use of fossil fuels is expected, favouring the growth of renewable energy and carbon capture and storage technologies.
5. Conclusion
The comparison between nuclear energy and fossil fuels reveals that both energy sources have significant advantages and disadvantages.
Nuclear energy is cleaner in terms of greenhouse gas emissions and has the potential to be a sustainable source of energy, although nuclear waste issues and associated safety risks remain major concerns.
On the other hand, fossil fuels, despite being cheaper in terms of initial investment and easier to implement, have a much greater environmental impact due to their emissions of CO₂ and other pollutants.