Nuclear Energy: A Closer Look
Nuclear Energy. As we move into the future we are constantly looking for ways to be more sustainable in everything we do. With that, energy practices constantly come under scrutiny for their potential impacts on the environment. As our population grows, so does the demand for resources. This makes it more difficult to keep up with the increasing demand for supplies while trying to move towards sustainable infrastructure. This is where energy practices come into play. As we move further into the future with the population increasing exponentially it is imperative that our society finds ways to sustainably power our growth. Doing so will open more opportunities for us to develop a stronger, working relationship with the Earth. If we want to continue to populate this beautiful planet, we need to be receptive to more ways to be sustainable in our energy production practices.
When it comes to energy production in the United States, there are multiple different sources to pull from. In 2019, 37% of the nation’s energy consumption was stemming from petroleum, alongside natural gas at 32%, renewables and coal at 11% each, and nuclear at 8% (1). The two largest problems that arise when looking at this data are the nuclear and renewable energy impacts. Compared to natural gas, petroleum, and coal, nuclear and renewables are far more sustainable and advantageous for the environment, but they aren’t being utilized as much as the other methods. We know that renewable energies face scrutiny from big coal and oil as it has the possibility to overtake these industries, but what about nuclear energy? Well, the answer isn’t so clear.
The Manhattan Project & Fission
During much of World War II, the United States Government was working on a top-secret development called the Manhattan Project. The goal of the project was to research and develop a bomb using atomic energy. While the United States was successful in their goal, atomic energy would end up being around long after the war, and for other purposes than just warfare. At the end of World War II, scientists quickly discovered that they could use their findings from atomic bombs and apply them towards energy resources. Thus, nuclear energy was born.
Today, our nuclear energy is powered by a scientific process called fission. In scientific terms, fission occurs when a neutron is slammed into a larger atom, causing that atom to split into two smaller atoms, and leading to a chain reaction (2). Enormous amounts of energy are released when each atom splits, and that energy is used to heat water into steam, which spins a turbine to create nuclear energy. In Figure 1 below, you can see an animation further detailing how fission works on an atomic level. As you can see, as one atom splits it causes a chain reaction, where the other atoms split due to the emergence of a neutron from the previous reaction.
Figure 1: Uranium Chain Reaction, Fission (4)
As previously mentioned, when these atoms split, they release mass amounts of energy. That energy is what is then used to heat pools of water, which turn into steam. The steam is what you see coming out of the smokestacks at nuclear energy production facilities. This steam often gets mistaken for smoke, which leads people to believe that nuclear energy is harmful for the environment. While nuclear energy does not emit carbon dioxide, critics often look towards its fuel source, uranium, in order to cast doubt on its practices.
Uranium is quite important in the process of creating nuclear energy. Other energy practices use oil, coal, and natural gas to power their production. Inherently nuclear energy is much cleaner than these other alternatives and it is due in part to the fuel source it uses – uranium. Interestingly, the energy created from one pellet of uranium fuel is equal to one ton of coal, 149 gallons of oil, and 17,000 cubic feet of natural gas (3). Since uranium is not found in nature in the state that it is needed to be in in order to be inserted into a nuclear reactor, it must complete four primary processing stages in order to be usable for nuclear fuel. The four stages include mining and milling, conversion, enrichment, and fuel fabrication (3). The four stages can be explained in further detail in the table below.
|Mining and Milling||Uranium is mined and milled when carbonated water is jetted through underground deposits and uranium is driven up to the surface|
|Conversion||Natural uranium needs to be converted to the isotope uranium-235 in order to prepare it for enrichment|
|Enrichment||Enriching uranium requires special facilities, which can be largely found in the U.S., France, Germany, the U.K., and Russia. Once the uranium is enriched, it is converted powder and then further pressed into fuel pellets|
|Fabrication||Fabrication is the process of loading the pellets into fuel assemblies, which feed the uranium into nuclear reactors|
Table 1: Uranium Processing Steps (3)
Naturally, once the uranium fuel is loaded into a nuclear reactor, it develops a lifespan. On average, one fuel assembly for a reactor lasts for about 5 years (3). This is where problems begin to arise as storing the used fuels and nuclear waste present issues for governments and private businesses alike. The used assemblies are often stored at the energy plants in steel-reinforced concrete containers (3); however, these are not meant to house the waste for the long-term. Along with storage concerns regarding uranium, there are also concerns regarding how it is mined. It has been found that the greatest risk for humans regarding uranium mining is lung cancer. Lung cancer can develop by inhaling uranium decay products, something that those mining the uranium could potentially be exposed to (16).
Nuclear Waste & Disposal
Nuclear waste, used assemblies, and used fuel, all refer to the same thing; the fuel that has been burned in a nuclear reactor. Nuclear waste is tough to store due to its radioactive nature. Because of this, many different solutions have been proposed and implemented in order to safely store the used fuels for the long-term. Of them all, the two most popular are near-surface disposal and deep geological disposal. Near-surface disposal is best suited for low-level and short-lived intermediate-level radioactive waste. It involves disposing of and storing nuclear fuels in caverns just below the Earth’s surface or even at ground level. On the other hand, long-lived radioactive waste must be stored further underground in deep geological disposals in order to safely store the radioactive materials away from humans and other wildlife. By storing the radioactive waste deep underground, the solid rock formations act as a natural barrier for the radiation. This serves as a long lasting and low-upkeep solution for storing radioactive waste. This is why many countries, including the USA, have chosen deep geological disposal as their method of choice for storing radioactive waste for the long term (5). While we seem to have a solution for storing the nuclear waste, some critics still argue that nuclear energy shouldn’t be practiced due to the potential risks it poses to human life such as cancers, genetic issues, and further finding its way into water supplies (14).
Figure 2: Nuclear Waste Disposal (13)
On March 28th, 1979 the United States experienced its most serious accident in commercial nuclear energy history at Three Mile Island in Pennsylvania. Essentially, a mechanical failure coupled with human error/misguidance led to a partial meltdown of one of the reactors on Three Mile Island. While a nuclear meltdown is nothing to joke about, the health effects due to the Three Mile Island incident were found to be minimal compared to the potential outcome. It was found that nearly 2 million people were near the reactor during the accident and were exposed to about 1 millirem above the usual background dose of radiation. Put into perspective, the amount of exposure one receives from an x-ray is about 6 millirem. It was also found in the months after the accident that no adverse effects on humans, animals, and plants could be attributed to the partial meltdown (6). In addition to these findings, studies from Columbia University and the University of Pittsburgh concluded that “in spite of serious damage to the reactor, the actual release had negligible effects on the physical health of individuals or the environment” (6). With this, we can infer that while the accident on Three Mile Island was not as catastrophic as it could have been, we need to be safer in our practices if we want to continue to use nuclear energy. If a practice is detrimental to nature and humans alike, we should look to stop or rethink the way we go about it in order to preserve life to the fullest extent.
Figure 3: Three Mile Island, PA (12)
In 1986 the world was yet again shown what can happen if nuclear energy is not properly extracted and produced. However, this time the effects of the disaster would be much graver than before. The Chernobyl accident is one that has attracted lots of attention over the years for its destruction, effects on the environment, controversy, and recently its involvement in an HBO series. According to world-nuclear.org, the Chernobyl nuclear disaster was the result of a “flawed Soviet reactor designed coupled with serious mistakes made by plant operators. It was the direct consequence of Cold War isolation and the resulting lack of any safety culture” (7). Yet again, we can see that a nuclear disaster has been caused mostly due to flawed machinery and/or human error. Due to the way the reactor exploded, radioactive substances were spewed into the air and surrounding environment for 10 days before it could be stopped. In all, 30 operators and firemen died due to the accident and 134 cases of Acute Radiation Syndrome (ARS) were confirmed in the months following the meltdown. Of those, 28 died as a result of ARS (7). With a meltdown of this magnitude, the larger question becomes, what about long term radiation exposure? Well, a UNSCEAR 2000 report showed that “apart from thyroid cancer increases, there is no evidence of a major public health impact attributable to radiation exposure 14 years after the accident” (7). However, this is just one report. There is a great chance that the UNSCEAR 2000 report is not totally accurate and as we have already seen, the radiation exposure alone can be detrimental to human life. With this information we can see that the meltdown did have serious effects on human life and that nuclear accidents are catastrophic and horrible for both humans and the earth.
Figure 4: Chernobyl Accident (11)
The last and most recent nuclear disaster that we are going to discuss is Fukushima. In March of 2011 Japan was struck with a serious earthquake that triggered tsunami waves. The waves ended up damaging the backup generators at the Fukushima nuclear energy plant. The loss of the generators allowed for cooling systems to fail, which in turn allowed residual heat to rise in the core of three different reactors, leading to a partial meltdown and release of radiation (8). The government of Japan moved swiftly and promptly to clear out local residents to avoid the risk of radiation exposure to the general public, something the Soviet Union failed to do. By evacuating residents, the government was able to shield them from potential radiation exposure that was a product of the partial meltdown. The Fukushima accident is a direct result of natural disasters leading to a nuclear accident. Thankfully, the Japanese Government and others were able to decrease the contamination levels over time. The image below is helpful in explaining how Japan managed this partial meltdown. By employing an exclusion zone surrounding the plant, Japan was able to evacuate the surrounding areas and focus on specific problems that could arise due to the meltdown. Sadly, it has been found that the Fukushima accident was the “largest accidental source of radionucleotides in the ocean” (18) in human history. With this alone we can infer that the potential negative outcomes of nuclear energy far outweigh its positives to humanity and the environment.
Figure 5: Fukushima Accident and Exclusion Zone (8)
After discussing the three main nuclear energy accidents in human history, it can be seen that while these accidents were harmful to humans, animals, and plants alike, they mostly due to human error, mechanical error, and natural disasters and for that we can only blame ourselves. These accidents have shown us that we humans are the problem when it comes to these accidents. By placing nuclear energy plants in safer areas, using proper and updated machinery, conducting educated and safe nuclear energy practices, or even just phasing nuclear energy out as whole, we can prevent accidents like these from ever occurring again. Nuclear energy has shown us just how detrimental it can be to both humans and the environment when mishandled. With all things considered and while nuclear energy poses some benefits, the negatives outweigh the positives as we have shown over the past that we are not capable of harnessing and processing this power without mistakes, and those mistakes can be grave for the world around us.
Of course, it is of utmost importance to protect the environment and humanity. Upon further examination, it has been found that nuclear energy does not contribute to global climate change as they produce no greenhouse gasses (17) , but that its waste and byproducts can pose threats via environmental and terroristic concerns. If nuclear waste is exposed to the environment, it can degridade it to the point where it can no longer be habitable to humans and be a serious danger to the animals that live there. If someone was able to expose a group of people to nuclear waste, it could be regarded as an act of terror as it ruins and potentially ends the lives of those that live there (15).
Here we are, nearly 80 years after the Manhattan Project we are getting closer and closer to unlocking an almost inexhaustible energy source- Nuclear Fusion. As previously discussed, all current nuclear reactors run off of nuclear fission. Nuclear fusion is different in that it offers a nearly infinite power source. Fusion works by heating different isotopes until they reach speeds high enough to quite literally fuse together, which in turn releases energy (9). This can be contrasted against fission, where isotopes are divided to cause a release in energy. So, if both fission and fusion release nuclear energy, why do we need to research fusion? Well, fusion technology represents a first for mankind in that it will allow us to harness the closest form of infinite energy that we can attain. Currently, fusion is shown to yield four times as much energy as fission (9). Scientists have been actively working on fusion technology and some expect to see fusion plants being build beginning in the 2040’s (9). If we can achieve nuclear fusion and couple it with other sustainable and renewable energy practices around the globe, we can make a serious impact on global warming and protect our planet for further generations.
Figure 6: Nuclear Fusion (10)
At this point we have reviewed the history of nuclear energy and everything that has come with it. With that, we can see that it has had some serious effects on humans and the environment alike. Even though nuclear energy is shown that it can play a key role in the transition to cleaner energies, the risks that come with it do not outweigh the benefits. In the 21st century we have access to many other renewable energy sources such as solar and wind power, where their potential risks to life are far less than those of nuclear resources. With that, we can see that while nuclear energy does provide some progress in the hunt for clean energy, it is not the final answer. We live in a world where if we allocate enough time and resources to any problem then we will be able to solve it, and this is just another example of that. The human race needs to appreciate what methods brought us to where we are, but we have to keep advancing into cleaner energy alternatives such as wind and solar power if we want to continue to inhabit this beautiful planet that we call home.