Nuclear Power Station Advantages and Disadvantages
As the human civilization has advanced, so have the energy demands of humankind. The modern world requires huge amounts of energy resources to sustain its need. For over a century, these energy demands have been satisfied by fossil fuels.
However, the energy demands have increased significantly and it has been recognized that the un-renewable fossil fuel reserves will not be able to satisfy the global energy demands for long. This together with the observed negative environmental impacts of the sources has necessitated the search for alternative energy sources.
Nuclear energy has emerged as a potential alternative energy source to fossil fuel. Loyn (2011) declares that while there are other alternative sources of energy, nuclear power is the most reliable and sustainable one.
The technology to exploit nuclear power has already been well developed and as of 2011, nuclear power stations were supplying 6% of the worlds energy needs. This suggests that nuclear power is a feasible replacement to fossil fuels as a primary source of energy for the world.
Nuclear power refers to the process of creating heat through a nuclear reaction and then harnessing this heat to produce electricity. It was an offshoot of the nuclear weapons industry. After scientists successfully learned how to build the atomic bomb, government funded research and development was committed to civilian application and nuclear development.
Researchers hoped to be able to harness the enormous energy produced by nuclear reactions for peaceful use. Governments have continued to play a crucial role in the nuclear industry and Western governments have expended significant financial resources to the development of nuclear power.
The US government spent $70 billion between 1948 and 1998 while the OECD governments had spent $318 billion by 1992 on nuclear energy research and development (Caldicott, 2006).
Nuclear energy encompasses two varying but related forms of reactions fission and fusion. In nuclear fission, nuclear power is produced by splitting a radioactive isotope of a heavy element into two or more smaller nuclei (Benedict, 1971). The newly formed nuclei are positively charged and they repel each other thereby traveling at high speeds in opposite directions.
If there are other fissionable atoms nearby, they may be induced to fission by colliding with the high speed traveling nuclei from the first fission atom and this creates a chain reaction (McKinney & Schoch, 2012). The chain reaction taking place due to nuclear fission has to be controlled. If it is allowed to go on in an uncontrolled manner, it will lead to a nuclear meltdown.
Control rods are the devices used to regulate the nuclear fission process. These rods are made of material that readily absorbs neutrons, such as cadmium and boron. The nuclear chain reaction can be completely stopped by inserting the control rods fully into the nuclear reactor.
In the fusion process, the nuclei of light elements fuse together to form heavier elements. An enormous amount of energy is released in this process thereby creating nuclear power. The first artificial fusion reaction was attained when the US detonated a hydrogen bomb in 1954. However, controlled and sustained fusion reactions are not yet feasible as a commercial energy source.
The lack of success in harnessing energy from the fusion process for commercial energy production is due to the extremely high temperatures needed to initiate the fusion reaction. McKinney and Schoch (2012) reveal that researchers are working to come up with a practical means of producing the extremely high temperatures needed for fusion and to contain the fusion reaction after it gets started.
How Nuclear Power Works
All modern nuclear power plants make use of the fission process to produce energy. A great amount of energy is required to split an atom and to accomplish this a nuclear reactor, which is a machine that at atoms at great speeds, is used.
The reactor consists of a core, which has the nuclear fuel (usually uranium), a moderator to slow neurons down, and control rods to regulate the rate of the fission process (Sivanagaraju, 2010). When the nuclear power plant is in operation, vast amounts of heat energy are generated in the reactor core. Water is used as the main coolant for the core.
The water in the nuclear power plant is contained in a primary and a secondary loop. The primary loop circulates around the core and its water directly cool the core. During the cooling process, the water in the loop absorbs the cores heat energy. Lilley (2010) states that the water in the primary loop is push under high pressure to retain it liquid form.
The primary loop is exposed to the core and the water in it potentially becomes radioactive. The water is therefore recycled and not exposed to the environment. The secondary loop contains water that is heated by the primary loop through a heat exchanger.
This heat turns the secondary loop water into steam. Since the water in the secondary loop does not come into direct contact with the primary loop water, it is not radioactive. The steam is therefore used directly to turn turbines in generators and produce electricity.
Advantages of Nuclear Power
Nuclear power reduces the negative environmental impact that electricity generation activities cause. Without nuclear power, industrialized countries such as the US would have to rely overwhelmingly on coal burning to generate electricity. McKinney and Schoch (2012) assert that coal causes severe environmental degradation as harmful greenhouse gases are produced and harmful particles are introduced into the environment.
The other major source of electricity generation is hydro power plants and these facilities result in significant pollution to the environment. Hydroelectric power plants lead to flooding in the upstream areas and encourage the proliferation of disease-bearing organisms due to the disruption caused to natural water flow.
Nuclear energy provides the only feasible solution to provide for the growing electricity demands in the world. The global electricity demand is expected to double in the next 2 decades (Hore-Lacy, 2011). Nuclear energy is able to provide continuous reliable supply to meet the global energy demands. To reduce the reliance on the , renewable alternatives such as wind and solar energy have been proposed.
Many nations have established power plants that harness these resources to produce electricity. However, these alternatives suffer from a lack of reliability. Wind power relies on the presence of substantial amounts of wind while solar energy requires the continuous radiation from the sun. For these two alternatives to be exploited, the power station has to be fitted with substantial back-up capacity in order to provide continuous energy.
The prices for the fuel for nuclear reactors is low and relatively stable making the unit cost of electricity from nuclear power stations fairly predictable (Sivanagaraju, 2010). The Fossil fuel prices are unstable and most times, they are escalating. This makes reliance on fossil fuels for electricity generation unreliable and expensive.
The price fluctuation has a negative economic impact on the countries that rely on fossil fuels for electricity generation. The price for uranium, which is the primary fuel for nuclear reactors, is stable which makes the cost of electricity from nuclear power stations steady over extended periods of time. Nuclear power stations are capable of providing cheap electricity especially when the power generated is large (Sivanagaraju, 2010).
After the initial capital expenses have been incurred, the running costs of the power station are low. The amount of energy obtained from a small amount of nuclear fuel also contributes to the reduction in the cost per unit.
Nuclear power plants have established themselves as the safest means of large-scale commercial power generation. Since the start of commercial nuclear energy production, nearly 6 decades ago, nuclear power generation has shown an impressive safety record (Benedict, 1971).
McKinney and Schoch (2012) reveal that the wide publicizing of the few nuclear accidents has caused the perception that nuclear power plants are unsafe. In reality, other sources of electricity generation have had many accidents and caused more deaths than nuclear power plants.
The use of nuclear power to produce electricity increases the energy dependence of a country. Most nations rely on the fossil resources to satisfy their energy production. Overdependence on fossil fuels leads to energy dependency on the nations that have huge fossil fuel reserves. The of the world are forced to spend a lot of foreign currency importing these products.
Nuclear power plants reduce the demands for coal, gas, and oil therefore promoting energy reliance in countries that lack fossil fuel resources. This increases the freedom of the country and also saves it millions of dollars that would have been used importing fossil fuels.
Nuclear power plants have less space requirements compared to other electricity production methods such as hydroelectric. This is a major advantage since land is becoming a scarce resource as the human population increases and more land is required for industrial activity.
The limited space requirements of nuclear power stations mean that they can be constructed relatively nearer to the load center in order to reduce transmission losses.
Nuclear power makes use of nonrenewable resources, which means that this source of energy cannot provide for humanitys energy needs indefinitely.
Loyn (2011) documents that uranium, which is the main fissile fuel use in nuclear reactors, is a finite resource and the available uranium deposits are expected to run out in about 100 years. The widespread availability of uranium is already diminishing as more nations set up nuclear power stations. Nuclear power can therefore not be relied upon to provide energy for generations to come.
Nuclear power plants produce toxic waste that can be harmful to the environment. Nuclear plants make use of uranium and plutonium to produce the heat energy through the nuclear reaction. Once these raw materials have been used for the production of nuclear energy, they are radioactive in nature and must be stored safely.
Meisen and Hunter (2007) document that these toxic byproducts have a very long half-life and they must be stored safely for thousands of years. A nation that wishes to use nuclear power to generate electricity has to invest in a sophisticated waste disposal program.
Nuclear power plants require large quantities of water during routine operations. This water is used for cooling purposes and for turning the turbines to generate electricity. While most of the water is reused in the operation, significant water is released into the atmosphere therefore making the water requirements for the power plant great (Caldicott, 2006).
The huge water requirements make it expensive for nuclear power plants to be constructed at locations where there is no large water supply. In addition to this, nuclear power plants lead to the contamination of water since the water in the primary loop becomes radioactive due to contact with the core.
The mining and processing of the uranium resources necessary to fuel nuclear power plants has a major impact on the environment. Uranium is found in small concentration and a significant amount of uranium ore has to be mined in order to extract uranium from the earth.
McKinney and Schoch (2012) state that more than 140,000 metric tons of uranium ore has to be mined to supply the uranium fuel consumed by a 1,000-megawatt capacity nuclear power plant annually.
Caldicott (2006) reveals that as more nuclear power plants are commissioned, the demand for uranium will increase and this will deplete the high-grade deposits of uranium ore making it necessary for more land to be mined in order to extract the uranium.
The level of damage in case of a major disaster in a nuclear power plant would be catastrophic. McKinney and Schoch (2012) chillingly warn that the typical modern nuclear power plant contains within its walls radiation equivalent to that of a thousand Hiroshima bombs (p.223).
In a worst-case nuclear accident scenario, up to 100,000 immediate deaths would occur and tens of thousands of subsequent deaths would follow due to radiation poisoning.
The Chernobyl disaster of 1986 demonstrated the huge environmental implications that a nuclear power station accident can cause. Chudley (2012) documents that this accident led to the severe contamination of over 10,000 square kilometers of territory in former USSR
Is Nuclear Power Friendly to the Environment?
Nuclear power presents an additional danger to the environment since an accidental spillage has adverse effects on the surrounding environment. Caldicott (2006) warns that there is danger of the huge quantities of radioactive waste accumulating from nuclear power leaking and contaminating drinking water and food chains in many parts of the world.
In addition to the risk of accidental spillage, nuclear power plants are making the environment unsafe. Nuclear power plants emit routine radiation that may be dangerous to the environment. Caldicott (2006) states that the radioactive elements released from the nuclear fuel cycle cause damage to living cells.
The environment is in constant danger from the harmful byproducts of nuclear power stations. Nuclear power plants produce toxic radioactive waste that must be safely stored to avoid environmental contamination.
Caldicott (2006) states that a regular 1,000 megawatt nuclear power plant generates 30 tons of extremely dangerous radioactive waste annually. So far, a safe means of disposing of the deadly radioactive waste is yet to be developed.
However, it should be noted that the dangers to the environment all require catastrophic failures in the nuclear power plants. While nuclear power plants pose significant threats to the environment, the US Environmental Protection Agency (2012) asserts that these power plants are built with safety considerations as a priority. The reactor plants are shielded to ensure that the radiation is contained and does not escape into the environment.
The impressive safety record of nuclear power stations all over the world suggests that nuclear energy is actually friendly to the environment. In addition to this, nuclear power plants reduce the environmental effects caused by traditional energy production methods since they do not release any harmful gases into the environment.
The Future of Nuclear Power
Nuclear power plants promise to reduce carbon emissions while at the same time guaranteeing energy security for decades to come. However, this energy production method can still be improved upon. At the present, the nuclear power generation plants make use of nuclear fission. Loyn (2011) states that nuclear fusion is yet to be developed for use in civilian power stations.
Hore-Lacy (2011) reveals that it is hoped that by the time the uranium supplies in the world are exhausted, nuclear fusion will be an option. If this technology is perfected, the society will be able to benefit from the enormous amount of energy produced from this process. In addition to this, the resources needed for nuclear fusion are in abundant supply.
Loyn (2011) reveals that Deuterium, the isotope of hydrogen used in nuclear fusion, can be extracted from ordinary water. Since ordinary water is available in abundance, nuclear fusion can provide enough energy to last humanity for millions of years.
The major disadvantages attributed to nuclear power plants are associated with the use of fission reactors. If major developments are made in fusion technology, these demerits of nuclear power will be eliminated.
Scientists agree that fusion would be an ideal energy source since it would provide enormous amounts of energy from an infinite resource (ordinary water) and without the radioactive waste products that fission produces (Loyn, 2011).