Nuclear energy is the energy held in the nucleus of an atom; it can be obtained through two types of reactions fission and fusion. Simply put, fission is the splitting of an atom into two. Fusion is when two light atoms combine to form a heavier atom as a result of nuclear reactions. Therefore, fission and fusion are opposite processes that are very different from each other.
Nuclear fission produces energy through the splitting of atoms, which releases heat energy that that can generate steam and then be used to turn a turbine to produce electricity. All of today’s nuclear plants use fission to generate electricity. The fuel most commonly used for fission is uranium, although additional elements such as plutonium or thorium can be used.
Nuclear fusion is a nuclear reaction in which two or more atomic nuclei collide at a very high speeds and join to form a new type of atomic nucleus. During this process, matter is not conserved because some of the matter of the fusing nuclei is converted into photons, which produces usable energy. This process is what allows the sun and stars to give off energy. Fusion power offers the prospect of an almost inexhaustible source of energy for future generations; however, creating the conditions for nuclear fusion presents a potentially insurmountable scientific and engineering challenge . A recent experiment in China has shown that nuclear fusion can be achieved, however, it has not yet been successfully demonstrated on a commercial scale. Nuclear energy, through fission, can release 1 million times more energy per atom than fossil fuels. It can also be integrated into electricity grids, which currently utilize fossil fuel generation, with few changes to existing infrastructure.
Today, nuclear power plants account for 11% of global electricity generation with about 80% of that installed capacity being in OECD countries. All of this capacity is nuclear fission.
Nuclear has large power-generating capacity and low operating costs, making it ideal for base load generation. However, up front capital costs are intensive and present financial risk to investors given the extended time frames power plants must operate to recuperate their costs.
Nuclear energy does not emit greenhouse gas emissions. For this reason, it is often seen as a substitute for fossil fuel energy generation and a solution for mitigating climate change.
However, nuclear fission has a wide variety of environmental and health issues associated with electricity generation. The largest concern is the generation of radioactive wastes such as uranium mill tailings, spent (used) reactor fuel, and other radioactive wastes. Some of these materials can remain radioactive and hazardous to both human health and the environment for thousands of years. Several large nuclear meltdowns in history released radioactive waste that had lasting negative impacts on the environment and surrounding communities. This has made nuclear fission technologies controversial.
Why there is an Opposition to Nuclear Energy?
If we look at the reasons for the opposition to nuclear energy under headings:
- Nuclear waste problem: The waste generated by nuclear reactors remains radioactive for long years. Currently, there are no long-term storage solutions for radioactive waste, and most is stored in temporary, above-ground facilities is seen as a risk.
- Nuclear proliferation: There is great concern that the development of nuclear energy programs increases the likelihood of proliferation of nuclear weapons. As nuclear fuel and technologies become globally available, the risk of these falling into the wrong hands is increasingly present.
- National security concers: Nuclear power plants are thought to be a potential target for terrorist operations. There are concerns that an attack could cause major explosions, putting population centers at risk, as well as ejecting dangerous radioactive material into the atmosphere and surrounding region.
- Accident risks: Human errors and natural disasters can also lead to dangerous and costly accidents. It brings to mind the examples of Chernobyl and Fukushima.
- In addition to all these topics, thoughts such as the perception that the increase in cancer cases is caused by nuclear power plants, the high cost of installing nuclear energy and the scarcity of suitable and sheltered power plant sites form the basis of nuclear opposition.
False Facts
Although the risks and concerns listed above are to some extent justified, there are misinformation and misconceptions created in societies. The most important of these is the prejudice that nuclear energy is bad for the environment and not safe. Nuclear reactors emit no greenhouse gasses during operation. Over their full lifetimes, they result in comparable emissions to renewable forms of energy such as wind and solar. Nuclear energy is as safe or safer than any other form of energy available. Used nuclear fuel can be recycled to make new fuel and byproducts. Most of the waste from this process will require a storage time of less than 300 years. In addition, safer storage projects have started to be implemented with geological storage as a storage method. All of the used nuclear fuel generated in every nuclear plant in the past 50 years would fill a football field to a depth of less than 10 yards, and 96 % of this waste can be recycled. The U.S. National Academy of Sciences and the equivalent scientific advisory panels in every major country support geological disposal of such wastes as the preferred safe method for their ultimate disposal. In the longer-term, nuclear power can directly reduce our dependence on foreign oil by producing hydrogen for use in fuel cells and synthetic liquid fuels.
Nuclear Energy Debates
Our world is changing. These changes increasingly take the form of higher temperatures and other climate impacts, creating a global push to limit our reliance on greenhouse gas-emitting energy sources. Nuclear energy is the largest zero-carbon energy source in the United States. In combination with other low- or zero-carbon energy sources, nuclear energy offers numerous benefits that make it uniquely suited for supporting a future clean energy economy. In Figure 1, statistics on the cleanliness and reliability of energy types all over the world are compared.
Proponents of nuclear energy argue that nuclear power is a clean and sustainable energy source which provides huge amounts of uninterrupted energy without polluting the atmosphere or emitting the carbon emissions that cause global warming. They advocate that the use of nuclear power provides plentiful, energy security, reduces dependence on imported fuels, and exposure to price risks associated with resource speculation and Middle East politics. Proponents advance the notion that nuclear power produces virtually no air pollution, in contrast to the massive amount of pollution and carbon emission generated from burning fossil fuels like coal, oil, and natural gas.
Modern society demands always-on energy to power communications, computer networks, transportation, industry and residences at all times of day and night. In the absence of nuclear power, utilities need to burn fossil fuels to keep the energy grid reliable, even with access to solar and wind energy, because those sources are intermittent. Proponents also believe that nuclear power is the only viable course for a country to achieve energy independence while also meeting to reduce carbon emissions in accordance with the Paris Agreement signed by 195 nations.
Opponents say that nuclear power poses numerous threats to people and the environment and point to studies in the literature that question if it will ever be a sustainable energy source. These threats include health risks, accidents and environmental damage from uranium mining, processing and transport. Along with the fears associated with nuclear weapons proliferation, nuclear power opponents fear sabotage by terrorists of nuclear plants, diversion and misuse of radioactive fuels or fuel waste, as well as naturally-occurring leakage from the unsolved and imperfect long-term storage process. They also contend that reactors themselves are enormously complex machines where many things can and do go wrong, and there have been many serious nuclear accidents. Critics do not believe that these risks can be reduced through new technology. They further argue that when all the energy-intensive stages of the nuclear fuel chain are considered, from uranium mining to nuclear decommissioning, nuclear power is not a low-carbon electricity source.
In terms of energy security, for some countries, nuclear power affords energy independence. Nuclear power has been relatively unaffected by embargoes, and uranium is mined in countries willing to export, including Australia and Canada. However, countries now responsible for more than 30% of the world’s uranium production: Kazakhstan, Namibia, Niger, and Uzbekistan, are politically unstable.
According to Sovacool (2011), reserves from existing uranium mines are being rapidly depleted, and expected shortfalls in available fuel threaten future plants and contribute to volatility of uranium prices at existing plants. Escalation of uranium fuel costs decreased the viability of nuclear projects. But one assessment from the IAEA showed that enough high-grade ore exists to supply the needs of the current reactor fleet for 40–50 years.
In the 2010+ decade, with growing public awareness about climate change and the critical role that carbon dioxide and methane emissions plays in causing the heating of the earth’s atmosphere, there was a resurgence in the intensity of the nuclear power debate. Nuclear power advocates and those most concerned about climate change point to nuclear power’s reliable, emission-free, high-density energy, alongside a generation of young physicists and engineers working to bring a new generation of nuclear technology into existence to replace fossil fuels.
Dr. Lütfi TAŞKIRAN
References:
- Benjamin K. Sovacool (2011). “The “Self-Limiting” Future of Nuclear Power”. Contesting the Future of Nuclear Power. World Scientific. Archived from the original on 2011-05-15. Retrieved 2011-07-29.
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