The Uncertainty and Disadvantage of Nuclear Power

NE 471

Dr.Chang

South Carolina State University

ANTRON CALDWELL

ABSTRACT

The future global economy is likely to consume increasing amounts of energy considering the increasing demand for cheap, clean and reliable energy from developing countries such as India and China. Though there are technologies capable of supplying this energy these energy sources come at the expense of increased ozone damaging CO2 emissions. CO2 emissions are believed to be a significant contributor to the rise in the average temperature of the Earth’s climate known as global warming. In the United States electric power plants emit about 2.2 billon tons of carbon dioxide (CO2) each year, which is about 40% of the nation’s total carbon emissions (NRDC, 2014). It is generally accepted by climate scientist that if annual carbon emissions are not reduced by at least 80% by the year 2030 then there will be an increase of greater than 2°C (35.2°F) which is considered an acceptable safe level or approximately 4°C (39.2°F) by the year 2100 in the Earth’s climate temperature (Carrington, 2013). These increases in the Earth’s temperature would be catastrophic, however measures taken by the government through the Clean Air Act to regulate emissions from stationary and mobile sources, and groups such as the National Resource Defense Council (NRDC) have somewhat reduced the emissions from stationary sources such as power plants and mobile sources such as motor vehicles. These efforts must be accompanied with a reduction in the use of carbon emitting fossil fuel energy sources. The generation of electricity through nuclear energy reduces the amount of electricity produced with carbon emitting fossil fuels, which reduces overall greenhouse gas emissions. Since uranium contains two to three million times the energy content of fossil fuels such as coal, a 1000MWe electric power plant consumes approximately 3.2 million tonnes of coal each year while a nuclear power plant only consumes 24 tonnes of uranium per year to produce the same amount of power (WNA, 2012). The enormous gap in fuel requirements between the two energy sources is directly proportional to the gap in the amount of waste byproducts that produce. In the US alone coal-fired plants produce about 2249 lbs./MWh of carbon dioxide, 13 lbs./MWh of sulfur dioxide and 6 lbs./MWh of nitrogen oxides and additional emissions are generated through the mining and processing of coal (EPA), while nuclear energy saves about 2.6 billion tonnes of carbon dioxide worldly each year (WNA, 2012). Nuclear power plants do generate radioactive waste, however this radioactive waste is manageable through reprocessing or dry cask storage. Nuclear power also has the advantage of producing energy continuously regardless of weather conditions, which is a significant disadvantage of renewable energy sources. Although nuclear energy has significant advantages, no energy source is without disadvantages. The disadvantages and uncertainty of nuclear power for generating electricity according to articles from the IAEA and Mycle Schneider will be discussed in detail in this essay.

Introduction

Mycle Schneider is a Paris based energy consultant and nuclear analyst. Schneider has served as an advisor to both the European Parliament and the International Atomic Energy Agency (IAEA) on energy issues for more than 20 years and is also the lead author of the World Nuclear Status Reports. Schneider’s The World Nuclear Status Report for 2010-2011 titled Nuclear Power in a Post-Fukushima World will be used to assess the disadvantages of nuclear power. According to Schneider’s report the disadvantages of nuclear power are,

* Government subsidies and tax credits * Merely new growth compared to renewables * Catastrophic release of radioactive materials during accidents * Skyrocketing capital cost * Cost of generating electricity is not competitive with renewables * Threat of nuclear proliferation and spread of nuclear weapons * Less reliability and security of electricity supply * Nuclear power is linked to government decisions (politics)

These disadvantages are of course strictly the opinion of the author, but some of the listed disadvantages have significant bearings on the use of nuclear energy for power generation. The disadvantages outlined by Schneider are in line with the generally accepted disadvantages of nuclear energy outlined by the Environmental Protection Agency (EPA, 2013).

* Radioactive waste * Nonrenewable * Catastrophic accidents * High cost * National risk * Policy

Each of the disadvantages will be discussed in detail to assess their validity and possible solutions to overcoming the disadvantages. The disadvantages will also be compared to the advantages and disadvantages as outlined in the report by the International Panel on Fissile Materials titled The Uncertain Future of Nuclear Energy. The International Panel on Fissile Materials is an independent group of nuclear experts from 16 countries that aims to advance initiatives to reduce the world’s stockpile of weapons grade plutonium and uranium. Merely New Growth Compared To Renewables

In an effort to reduce greenhouse gas emissions and diversify the electric grid with clean energy sources more renewable energy plants are being built. Annual renewables capacity additions have been outpacing nuclear start-ups for 15 years. In the United States, the share of renewables in new capacity additions skyrocketed from 2 percent in 2004 to 55 percent in 2009, with no new nuclear coming on line (Schneider, Mycle 2011). Renewable energy sources such as solar, hydropower and wind power are being deployed steadily in areas capable of supporting these technologies. Compared to nuclear power deployments renewable technologies are being deployed at a much higher rate. Nuclear power is the most regulated industry in the world, which maybe a contributor to the delayed construction of new nuclear power plants while renewables have a much simpler licensing and construction process. The validity of this disadvantage hinges on the idea that renewable energy sources are able to generate as much energy as a single nuclear power plant. It turns out that this disadvantage is not valid, because even though far fewer new nuclear power plants are being constructed compared to renewables such as solar and wind a few new nuclear power plants will generate orders of magnitude more energy than multiple new solar or wind plants. Renewable energy sources are also far less reliable than nuclear power plants, because they depend on weather conditions or time of day and therefore must be supplemented with other energy sources to be remotely feasible. The usual supplement to solar and wind power plant is natural gas, which emits greenhouse gases albeit at lower amounts than coal fired plants. Nuclear power plants require no supplemental energy sources and operate continuously regardless of weather conditions. The required supplemental energy sources for renewable sources such as solar and wind means they generate more carbon pollution than nuclear power if you include the carbon emission generated during the mining and preparation of materials for each of the energy sources. Merely new growth new growth compared to renewables is the least significant disadvantage for nuclear power, and is actually a significant disadvantage for renewables, because of the requirement of a supplemental energy source that emits carbon pollutants. The chart below illustrates the lifetime carbon emissions of different sources of energy.

Skyrocketing Capital Cost

Capital costs are the upfront cost to construct and maintain a power plant over its lifetime. Among renewables solar is the most capital-intensive energy source, but is easily dwarfed the extreme capital cost of nuclear power plants (Green Rhino Energy).
The cost of building a nuclear power plant is determined primarily by the capital cost of the plant, this makes the cost of building a new nuclear power plant hard to quantify since the capital cost of a nuclear power plant can fluctuate as construction goes on. The current 'overnight cost' of the light water reactors being currently being constructed is about $4000/kWe with projected total generating cost of about $.10/kWh (Hippel, 2010, p.21). The overnight cost of constructing a nuclear power plant do not include interest that compounds over the 4-10 year construction period, this means that a 10% annual cost of capital can raise the cost of constructing a new power plant by 28-75%(Hippel, 2010, p.21). These cost are of course assuming no delays in construction, in which delays would cost the total capital cost of building a new nuclear power plant to increase even more. Some reasons for the staggering capital cost of building a nuclear power plant are attempts to make estimates of the increase in material cost relative to inflation rates, over estimates of total cost by utilities to achieve larger guaranteed loans, and low estimates by vendors in order to secure a contract to build a nuclear plant (under estimates cause the utilities to have to dedicate more capital eventually). In other industries cost usually reduces with increased efficiency and better methods of providing a good or service, however the nuclear industry does not really benefit from improved knowledge or innovation. Reasons the nuclear industry does not improve from improved industrial knowledge include fluctuating regulation standards and better understanding of potential problems as construction goes on, construction must be very accurate and precise because mistakes or defects may require builders to completely start over, and finally delays in construction increase interest charges. Since nuclear power plants have extremely high capital cost and comparatively low operating cost to maximize profits from a nuclear power plant they are usually operated at full power until they are shutdown for maintenance and refueling. The chart below shows that capital cost of nuclear power far exceeds the capital cost of any other electric generating source, this makes capital cost a significant disadvantage to the deployment and use of nuclear energy for generating electricity. Although new nuclear technologies promise to be both cheaper and safer than the current generation of nuclear technology by offering simplified plant designs (i.e. passive safety features that require less pumps for coolant systems and lower enrichment requirements) there will still be some first mover cost associated with new plants designs, which makes the capital cost of the next wave of nuclear power plants remain relatively high until enough new plants are offered.

The graph is adapted from green rhino energy.

Nuclear Proliferation and National Risk

Nuclear proliferation is the spread of nuclear weapons, fissionable materials and weapons applicable nuclear technology and information to nations not recognized as nuclear states. When the United States first started its journey with atomic energy the primary goal was to build nuclear weapons. In fact one of the major reasons light water reactors became the dominant reactor technology was their ability to breed plutonium. Fortunately 'reactor grade' plutonium is not suited for nuclear weapons, because plutonium 240 contaminations makes a nuclear weapon using 'reactor grade' plutonium very unreliable and unpredictable. Weapons grade plutonium is bred in special natural uranium fueled reactors that operate at low burn-up rates for short periods of time (i.e. 3 days) or just long enough to sufficiently irradiate the uranium 238 fuel. Nuclear energy has obvious benefits for mankind if used peacefully, the question is how do we promote the use of nuclear energy without spreading the ability to create nuclear weapons? The IAEA's Standing Advisory Group on Safeguards Implementation (SAGSI) identity a substantial amount of nuclear material as 8kg of Plutonium or Uranium 233, or 25kg of highly enriched uranium (HEU contains 20% or greater weight percent Uranium 235). Since the spontaneous fission of Plutonium 240 generates neutrons at steady albeit slow rate they can be used to initiate a fission chain reaction in implosion type nuclear devices such as the one used in the Nagasaki bombing. This means that a crude nuclear device can theoretically be built using reactor grade plutonium and therefore the SAGSI presents a more strict definition of a substantial amount of nuclear materials to include any amount of plutonium with less than 80% plutonium 238. A power reactor operating at 1000MWe produces 290kg of plutonium for every 25 tonnes of spent fuel (WNA). The plutonium in spent nuclear fuel is approximately 25% plutonium 240, 53% plutonium 239, 15% plutonium 241, 5 % plutonium 242 and 2% plutonium 238, which makes it direct usable material by the SAGSI definition. It should be noted that although plutonium 238 is the main source of heat and radioactivity from plutonium in spent fuel it is actually usable as material for peaceful purposes such as space exploration vehicles. The concern for using spent nuclear fuel to obtain plutonium is somewhat mitigated by the fact that it is extremely difficult and dangerous to steal and separate plutonium from intensely radioactive spent fuel bundles. Once through fuel cycles where Plutonium is not separated from spent fuel are more proliferation resistant than fuel cycles that incorporate reprocessing. For example Japan's Rokkasho Reprocessing plant is designed to separate 8 tons of Plutonium per year, however measurement errors make it impossible to verify the amounts of Plutonium actually being separated at the facility. This means that it is possible that a significant amount of nuclear materials can be obtained over a period of time by small measurement diversions. While the IAEA attempts to monitor nuclear states through the Nonproliferation Treaty (NPT) by requiring nuclear states subject to IAEA audits of their nuclear activities to ensure they are peaceful, the threat of nuclear weapon proliferation is a valid concern. The NPT requires nuclear weapon states such as the US to also comply with conditions of the NPT, which means IAEA audits and significant reductions in nuclear weapons inventory. Nuclear states that are not recognized as nuclear weapons state are prohibited from developing nuclear weapons. While the destruction caused by nuclear weapons is certainly a disadvantage of nuclear power, it is probably the most over exaggerated disadvantage of nuclear weapons. Agreeing not to build nuclear weapons does not remove the knowledge to build nuclear weapons, in times of war and desperation a nuclear weapons state that once complied with the NPT may decide to build and detonate a nuclear weapon. Even worse rogue countries like North Korea who do not comply with the NPT have the knowledge to build nuclear weapons and have made it public knowledge that they have the ability to build and launch a nuclear warhead. Technologies such as fast neutron reactors are capable of fissioning weapons grade material and other unwanted actinides as fuel without reprocessing, and mixed oxide fuels that mix depleted uranium with 4-8% weapons grade plutonium also help to reduce weapons grade material. For reasons discussed previously reactor grade plutonium is not suitable for making weapons and is probably not worth the effort to steal, however rogue terrorist groups could seek to destroy a power plant's cooling system forcing a meltdown and then damage the containment structure in order to purposely leak harmful radiation to the public. Newer reactor technology combats that the likelihood of this scenario by beefing up structural integrity, for example the new AP1000 reactor containment structures can withstand a direct plane crash without shattering. Building a nuclear bomb also requires a unique set of knowledge and is an extremely complicated device; there is much easier and cheaper ways for a terrorist group to cause damage. The major effect of nuclear proliferation is the negative public opinion of nuclear energy it brings, because most people generally only know of nuclear energy as a weapon of mass destruction. In fact as a nuclear engineering student I'm constantly asked if I want to build bombs. The poor public image of nuclear energy, because of nuclear weapons makes it difficult to convince people that nuclear energy is the answer to our energy demands is a sufficient reason to consider proliferation a disadvantage of nuclear energy.

The content of plutonium in spent nuclear fuel from power reactors. (The Neutron Economy, 2012)

Government Subsidies and Tax Credits

According to the Union of Concerned Scientist (UCS) nuclear power is not economical without governmental subsidies. Government subsidies for nuclear energy include government funded research and development efforts, limitations on liability for catastrophic accidents (i.e. Price Anderson Act), low cost and guaranteed loans, and guarantees of private investments. Apart from government funded research for nuclear weapons and propulsion systems (i.e. nuclear submarines) an estimated $166 billion was spent by Japan, the U.S., France, the UK and Germany between 1974 and 2007 on commercial atomic energy efforts. This is about $700kWe of nuclear capacity in the aforementioned countries as of 2008 (Hippel, 2010, p.24). The Energy Policy Act (EPACT) offered utilities incentives such as guaranteed loans of up to 80% of projected construction cost to entice utilities to invest in nuclear power plants in an effort to reduce carbon emissions from coal and natural gas fired power plants. In 2005 the proposed budget for the Energy Policy Act was $18.5, which was quickly overwhelmed with approximately $122 billion in loans being requested to cover 65% of the cost of building 21 new nuclear power plants. In 2011 the Obama administration proposed to raise the budget for EPACT to $54 billion (Hippel, 2010, p. 39), however it is clear that building nuclear power plants require significant government support. The Energy Policy Act also provides other incentives for investing in new nuclear power plants such as production tax credits of up to 1.8 cents/kWh of power generated with advanced nuclear power (i.e. generation III+ and Generation IV reactors) capacity in the first 8 years of operation. The majority of the states in the US (36 out of 50) regulate the investments of utilities in the generation and transmission of electric power, these regulations allow utility companies to pass the cost of building nuclear power plants on to consumers. For example in South Carolina the SCANA corporation has requested and been approve for multiple rate hikes to offset the cost of building the two new Westinghouse AP1000 nuclear reactors at its V.C. Summer power station. This presents a significant disadvantage for nuclear energy, because consumers are almost never game for price increases. Tremendous governmental spending on nuclear power may also meet ill public reception, especially from persons not convinced that nuclear power is the answer to our energy demands. Governmental support also fluctuates with different administrations. For example the current republican majority do not believe we should be investing in nuclear energy and shun climate science that suggest burning fossil fuels is a significant contributor to global warming, this means it will be very difficult to receive support from the current congress to build a nuclear power plant. A large hurdle to expanding nuclear capacity is public acceptance and although public acceptance of nuclear power has improved as seen in the chart below, there is still a large population of the public that does not approve of nuclear power. This means politicians can theoretically use anti nuclear policies to win popularity amongst voters. The fact that governmental subsidies and support is an intimate requirement for expanding nuclear power presents a huge negative for the use of nuclear energy as opposed to alternative energy sources such as coal or natural gas.

It is generally accepted that carbon emissions must be significantly reduced and therefore the government is likely to subsidize renewable energy technologies, in fact renewable technologies receive more subsidies than nuclear energy on a whole. Some states have recently started to tax utilities based on their carbon emissions in an effort to entice utility companies to find creative ways of generating electricity without excessively polluting the air. Since nuclear power plants do not emit any carbon dioxide this makes the cost of operating a nuclear power plant competitive with traditional sources such as natural gas. The table below outlines the share of governmental subsidies and support by energy source. It is observed from the table that outside of renewable energy sources nuclear energy is the most subsidized form of power production.

Safety and Radioactivity

A large portion of the fear of nuclear energy comes from the idea that nuclear power plants are constantly emitting harmful radiation into the environment, however this concern is completely invalid. In fact in some areas of the world such as Brazil the background radiation levels (naturally occurring) are much higher than any radiation ever emitted by a nuclear power plant. Ironically coal ash from burning coal in coal-fired power plants carries 100 times more radioactive waste into the surrounding environment than a nuclear power plant producing the same amount of energy (Teel, 2013).

The Chernobyl accident of 1986 is one of the most catastrophic nuclear accidents in history, however it’s not nearly as devastating as previously believed. About 40 people were killed and large portions of the previously evacuated residents have returned to the area. Reactors currently licensed in the US are much better built and safer than the RMBK reactor used in the Chernobyl power plant, which had a positive void coefficient that did not allow the reactor to decrease its reactivity in response to steam buildup. Generation III+ and generation IV reactors are even safer than reactors currently in operation, because they rely on passive and inherent safety features such as negative temperature coefficients that automatically shut the reactor down if the core becomes too hot. Nuclear safety has been improved through technological advances, therefore the answer to nuclear safety is not to shun nuclear power but instead to invest in newer nuclear technologies that are safer, more efficient, and cheaper than the current technology in operation.
Nuclear Accidents

The Price Anderson Act main purpose is to ensure the availability of a large pool of funds to provide prompt and orderly compensation for any person or persons of the public for any damages incurred because of a nuclear accident regardless of liability. The pool is currently $10 billion and power reactor owners are required to pay up to $96 million per reactor unit into a secondary insurance pool. In the event that the cost incurred by a nuclear accident exceed the limits established by the Price Anderson Act than the government can appropriate funds to cover damages. The benefit of the Price Anderson Act is that it ensures a sufficient pool of funds to compensate members of the public for damages incurred because of nuclear accidents and it provides an incentive for utilities to invest in nuclear power plants by removing the threat of potential liability claims following a nuclear accident. Even with proper appropriation of funds to cover material damages, nuclear accidents can also have catastrophic effects on the surrounding environments. The saying " a nuclear accident anywhere is a nuclear accident everywhere" holds true, because radioactive elements such as cesium can be carried large distances through the wind or even contaminate large bodies of water through ground water contamination. In fact radioactive waste was leaked into the Pacific Ocean through contaminated ground water during the Fukushima accident of 2011. It is very difficult if not impossible to clean up environments contaminated with radioactive elements, especially if the radioactive elements are long-lived isotopes such as plutonium. Long-lived isotopes will continue to contaminate an area while they decay. Nuclear accidents are also very hard to quantize, because radioactivity is invisible to the naked eye and it takes time to actually account for the amount of leaked radiation and accurately detail the damages caused by the accident. The cost of health physicist and other experts further drive the cost of nuclear accidents up. A commercial nuclear power plant can cost billions of dollars to construct and although it can be a huge asset for operators an accident can easily devastate any profits and benefits the operator once enjoyed. Nuclear accidents and their unforgiving nature is easily the biggest disadvantage of nuclear power. It should be noted that even though nuclear accidents are an extremely huge risk to consider when deciding whether or not to expand nuclear power, there has only been one nuclear accident in the United States and nuclear accidents have claimed far less lives than coal fired plants. The picture below shows the severity of past nuclear accidents on the INES scale, the location of the accident and the year of the accident. It is seen from the picture that there have been only two major nuclear accidents in the entire history of nuclear power.

The chart below compares the radioactive releases of the Fukushima accident of 2011 to the radioactive releases of the Chernobyl accident of 1986

Overcoming Disadvantages

Nuclear energy has some very daunting disadvantages, however the majority of the disadvantages of nuclear energy are solvable by technological advances. For example Liquid Fluoride Thorium Reactors (LFTR), which is a molten salt reactor that breeds uranium 233 from thorium, does not produce any transuranic waste products. The waste from LFTRs is actually quite useful for medical, industrial, and space exploration endeavors. For example the Plutonium 238 produced with the LFTR reactor is not a fissile material and certainly not weapons grade material is used in radioisotope thermal generators (RTGs) used by NASA in space exploration vehicles (i.e. Mars Rover). Advanced Reactor designs like the LFTR also offer superior safety features over current reactor technology such as decreasing power and rate of fission automatically because of fluid expansion if temperatures exceed a certain temperature, and the salt plug and drain tank which automatically drains the entire molten salt-fuel mixture into a subcritical tank incase of accident. By deploying generation IV reactor technologies such as the LFTR we can not only decrease the amount of nuclear waste that needs to be stored for generations but we can also achieve a more proliferation resistant fuel cycle and inherently safe nuclear energy industry. Establishing a standard nuclear reactor design much like we have a standard currency system can decrease capital cost of constructing a nuclear power plant. A standard nuclear reactor design has the benefit of a complete understanding of the total cost, which means the amount of guaranteed loans can be decreased. A standard reactor design also removes the incredibly long and expensive licensing process since the standard reactor design would already be extensively studied and critiqued by the NRC beforehand. Currently every nuclear power plant in operation is slightly different than the next, which means a nuclear reactor operator must be specifically trained and qualified on the reactor they intend to operate, this the complexity of actually operating and maintaining a nuclear power plant could be streamlined with a standard design. Vendors such as Westinghouse and General Electric can compete to become the standard reactor design. Modular reactor setups could be used to build appropriately sized nuclear power plants for the intended market, currently nuclear power plants are one size fits all configurations. This makes nuclear power plant components unable to be produced in local factories and mass-produced for quick construction of plants. Small modular reactors have the benefit of allowing small reactors to be manufactured in factories and shipped to power plants for easy scaling of electrical output capability. Properly educating the public through a required course during grade school or free seminars to the general public would go a long way in expelling the false ideals about nuclear energy and garnering support for expansion of nuclear power. There a number of technological advances in nuclear energy that are able to overcome a majority of the disadvantages of nuclear energy when coupled with proper policy and support.

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