Nuclear Power: A Clean, Safe Alternative
Jonathan Schrock
November 23, 1998

I. Introduction

II. Radiation

A. Properties
B. Comparison with other types
C. Average annual exposure from various sources

III. Electricity production

A. Current sources
B. Possible solutions to future energy crisis

IV. Nuclear power

A. Basics of reactor operation
B. Safety measures associated with reactor operation
C. High level nuclear waste
D. Yucca Mountain
E. Plutonium reprocessing
F. High level waste shipping

V. Conclusion

VI. Works Cited

As our population increases, so will our demand for electricity. Air conditioners, computers, televisions, microwaves, and many other appliances have become necessities for Americans. All methods of producing electricity have drawbacks. As the earth becomes warmer, we must look for ways to decrease our use of fossil fuels. There are several ways to produce electricity without releasing air pollution. The most feasible method at this time is nuclear energy. Nuclear energy presents a safe, clean, and inexpensive alternative to other methods of producing electricity. Nuclear waste can either be reprocessed or disposed of safely, provided certain precautions are taken.

In order to understand the risks associated with nuclear energy, it is necessary to understand the properties of radiation and their effects. The term radiation refers to a wide range of things. Ionizing radiation is the kind that can and does cause damage. Ionizing radiation creates ions when it strikes something, which can then affect matter such as human tissue. The two main types of ionizing radiation are electromagnetic and particle. Ionizing electromagnetic radiation includes x-rays, gamma rays, and cosmic rays. Ionizing particle radiation involves alpha particles, which are helium nuclei, beta particles or electrons, and neutrons. Gamma rays, alpha particles, and beta particles are the main forms of radioactivity associated with nuclear power (Taylor, 1996).

Comparison with other types
Radiation has many benefits for humans, but too much of any type of radiation can be harmful. For example, the sun gives off infrared radiation, or heat, as well as visible light, another type of electromagnetic radiation. These forms of radiation are necessary for humans to live, but too much can cause damage. At one extreme, too much infrared radiation would cause everything to burn up, and an excess of visible light would cause everyone to go blind. Another example is x-rays, which have become a valuable medical diagnostic tool. However, overexposure to x-rays can increase a person's cancer risk or even cause immediate death (Taylor, 1996).

Average annual exposure from various sources
The average American's exposure to radiation (82%) comes primarily from natural sources. Fifty-five percent comes from radon, which is given off by radium, a component of soil and rock. Americans receive a smaller percentage of radiation from other terrestrial sources, such as uranium in the soil, and from cosmic rays. Eleven percent of natural radiation exposure is internal, primarily from radioactive potassium in our bodies. Eighteen percent of American's radiation exposure comes from man-made sources such as x-rays, nuclear medicine, and consumer products, much of which is the necessary byproduct of beneficial products and procedures. Americans receive only 0.1% of their total radiation exposure from nuclear energy production. This figure includes exposure from mining, milling, reactor operation, transportation, and waste storage. Interestingly, Americans receive 0.5% of their total radiation exposure from the radioisotopes released into the atmosphere from coal-fired power plants. We actually receive five times as much radiation from coal-fired power plants as we do from nuclear power plants (Taylor, 1996).

Electricity Production
Current sources
As the population continues to grow, energy demands will continue to rise. The United States Department of Energy has estimated that energy use in the U.S. will increase by 20% by 2010 and 30% by 2015, requiring us to find ways to increase the amount of energy we can produce. Before proposing solutions to this future energy crisis, it is helpful to examine the sources of our electricity today before deciding how to fix tomorrow's problems. Coal currently provides most of the electricity (51%) in the United States. Twenty percent comes from nuclear power, 15% from natural gas, 9% form hydroelectric sources, 2% from oil, and 3% from other sources, such as wind and solar power. Each of these sources of electricity has its own advantages and disadvantages. Burning coal to produce electricity is inexpensive, and all of the coal we need can come from the United States, reducing our dependence on foreign suppliers. However, burning coal pollutes the air and produces large amounts of ash that must be disposed of. Natural gas is cheap right now, but supplies and prices fluctuate. Burning natural gas also produces air pollution. Hydroelectric power produces no pollution, but development of these locations can destroy the local ecosystems. Additionally, nearly all of the potential sites in the United States have already been developed. Oil is easy to use, but it creates air pollution and a dependence on foreign suppliers. Neither wind nor solar power creates any pollution and both have an unlimited supply, but both are too small-scale to solve all of our energy problems. Nuclear power also creates no pollution. It is economical, and there is a plentiful supply of fuel in the United States, avoiding dependence on foreign suppliers. The only significant drawback is that high level nuclear waste requires careful disposal (Nuclear Energy: Power for people).

Possible solutions to future energy crisis
An energy shortage in the next decade is inevitable. "Brownouts," lowering the operating voltage to prevent a blackout, are already common in some parts of the country. This approach to energy conservation can damage some electrical devices and is not a practical long-term solution to energy problems. Lauriston Taylor has proposed six practical solutions to this problem of energy shortages. First, power companies with an energy shortage should buy excess power from other regions. Electrical companies have been doing this for a long time; however, this works only as long as there are companies with extra power. Unfortunately, a power surplus in California does not help a power shortage in New England. Taylor then suggests developing and using solar power. The major problem with this approach is its dependency on the weather. The sun does not always shine when electrical demands are high. Another problem is that photovoltaic cells cannot transmit current directly. The energy from the solar power must be used to convert water to steam and have the steam turn turbines to produce electricity. According to Taylor, the large-scale use of solar energy to convert water to steam is at least fifty years away. A third potential solution increases our use of petroleum at a higher level of efficiency. However, this approach would only be practical if we decreased our use of petroleum in other areas, which is very unlikely. Her fourth suggestion involves building more coal-fired power plants. Our electricity production would surely increase, and there is enough coal to last for 400 years. However, coal adds radioactivity to the environment and releases toxic sulfur and nitrogen oxide gases into the air. Additionally, the coal reserves that are currently being mined are high in sulfur content, making them that much more harmful to the environment. Fifth, nuclear fusion, if understood, would solve all of our energy problems. However, development of nuclear fusion is a long way off, and no one has a good estimate of when it may be available. Taylor's final and most feasible solution involves increasing our use of nuclear energy. She notes that it does not create a dependency on foreign raw materials and has helped small countries with limited natural resources (Taylor, 1996).

Nuclear power
Basics of reactor operation
In order to evaluate the benefits and risks associated with nuclear power generation, a person must first understand what goes on inside a reactor. Commercial nuclear reactions use uranium as fuel for producing energy. One pound of uranium produces as much energy as six tons of coal or 1200 gallons of oil. Nuclear fuel is also very cheap, costing just 1/2 cent per kilowatt-hour. Natural uranium is made up of two isotopes: U-235, which is the fissionable isotope but accounts for only 0.7% of natural uranium, and U-238, which makes up over 99% of natural uranium but does not fission. In order for natural uranium to be used as reactor fuel, it must be enriched to 3-5% U-235. The first step in the enrichment process converts uranium to a gas. Solid uranium reacts chemically with fluorine to produce UF6, uranium hexafluoride, which is a gas at room temperature. A gas chromatography process then increases the U-235 content, and the enriched UF6 is then converted to uranium dioxide, a solid, and pressed into ceramic pellets. Old uranium-containing nuclear weapons are also being used for fuel. The U-235 content of these weapons ranges from 20-90% but can be diluted to 3-5% and used as fuel (NEI: Nuclear fuel, 1998).
The actual nuclear reaction takes place in what is called the reactor core. The uranium fuel pellets are put into tubes and then placed in the reactor. Neutrons are released and strike uranium atoms, which release their own neutrons and cause a chain reaction. Heat from fission turns water to steam, turning turbines to produce electricity. Control rods fit between the fuel rods and absorb neutrons. Inserting control rods into the reactor core slows down the reaction, whereas withdrawing them allows the reaction to speed up (NEI: The energy plant, 1998).

Safety measures associated with reactor operation
Several safety measures exist to protect against any release of radioactive material into the environment. The ceramic uranium fuel pellets resist the negative effects of high temperature and corrosion. Most of the radioactivity remains in the fuel pellets (NEI: Safety, 1998). The concentration of U-235 is kept low so that a nuclear explosion is impossible. Also, the chemical makeup of the fuel provides a natural control. As the reaction heats up, it slows down, since 96% of the fuel does not fission (NEI: The energy plant, 1998). The fuel pellets are placed in zirconium fuel rods, which resist heat, corrosion, and radiation (NEI: Safety, 1998). Water acts as a moderator of the nuclear reaction by slowing down the neutrons and increasing the probability that they will hit and fission a uranium atom. An increased level of steam slows the reaction, and if all water converts to steam, the reaction stops completely (NEI: The energy plant, 1998). The reactor core is located inside a steel pressure vessel with eight-inch thick walls. A huge steel-reinforced concrete containment structure with four-foot thick walls covers everything (NEI: Safety, 1998). Nuclear power plants also have backup systems to protect against almost every imaginable problem, including human error, equipment failure, floods, earthquakes, and tornadoes (NEI: The energy plant, 1998).

High level nuclear waste
Once the fission process has slowed, the fuel rods are replaced. The spent fuel rods contain highly radioactive fission products and must be stored safely. These used fuel rods are considered high level nuclear waste. Currently all high level nuclear waste is stored in large pools of water at the power plants where it was generated. Seven to ten feet of water is enough to stop all radioactivity (Keeny, 1998). Since the late 1950's, high level nuclear waste has been stored in this form, and there has never been any release of radioactivity. There is actually a relatively small amount of high level nuclear waste. All of the waste ever produced in the history of commercial nuclear power production in the United States would cover the area of a football field four yards high (NEI: High-level waste, 1998).

Yucca Mountain
In 1982, Congress established the Nuclear Waste Act, which placed a tax on all electricity from nuclear power (NEI: High-level waste, 1998). Nuclear power companies have paid the United States Department of Energy $14 billion in the past 15 years and are adding to that total at a rate of $600 million per year (Lloyd, 1998). The money was to be used to find a permanent repository for high level nuclear waste. In 1987, Congress directed the United States Department of Energy to focus on Yucca Mountain in the Nevada desert. Yucca Mountain is currently being studied to determine if it is a safe storage location. The researchers are concerned with three main issues: volcanoes, earthquakes, and water movement through the mountain. Yucca Mountain is an ideal storage site for high level nuclear waste for several reasons. In order for the radioactivity to reach the environment, water would have to enter the repository, dissolve some of the radioactive elements and carry them to the surface. Yucca Mountain receives very little rainfall each year and has a water table 1800 feet below the surface. Additionally, scientists everywhere agree that the best way to dispose of high level nuclear waste is to bury it deep underground in a repository that will protect people and the environment (NEI: High-level waste, 1998).

Plutonium reprocessing
An alternative to burying all of the used fuel is to recycle it. The original vision of nuclear power in the United States involved mining uranium, enriching it from the 0.7% U-235 found in nature, and using it as fuel in nuclear reactors. The spent fuel rods would then be sent to reprocessing plants. Plutonium, a waste product and suitable reactor fuel, along with any unburned uranium would be dissolved, chemically separated, and reused as fuel. The recycled fuel would first be used in conventional reactors, then later in breeder reactors, which produce plutonium. Breeder reactors make more plutonium than they consume, leading to a nearly unlimited source of energy. The capture of neutrons by U-238 (99% of natural uranium) forms plutonium. Breeder reactors can eventually consume all of the U-238 present in natural uranium by converting it to plutonium, increasing the amount of energy obtained from natural uranium by a factor of 100. The problem with reprocessing is that the chemical separation of plutonium for commercial purposes is the same process used to make nuclear weapons. On April 7, 1977, President Carter announced a ban on all reprocessing in the United States. He was mainly concerned about proliferation issues and was hoping to set an example for the world. Currently reprocessing is illegal in the United States, but some pro-nuclear activists are trying to change that.

The main fear behind the ban on reprocessing is that the separated plutonium would be diverted for weapons. Supporters of the ban on reprocessing point out that if, in the future, breeder reactors become widespread, each reactor could have several tons of plutonium stored on site, enough for 1000 nuclear weapons. Even with strict monitoring, this could obviously be dangerous. Citing a breeder reactor development attempt in North Korea, Spurgeon M. Keeny, Jr., chairman of the Nuclear Energy Policy Study Group which helped persuade President Carter to prohibit commercial reprocessing notes, "the pursuit of an unnecessary and wasteful plutonium economy is the last thing we need in a world struggling to prevent further nuclear proliferation" (Keeny, 1998). Another argument is based on economics. Currently, uranium prices are low and will remain so for a long time, so the reprocessing risks outweigh the benefits in the foreseeable future. In the last twenty years, there has never been a shortage of uranium or an increase in cost. Adjusted for inflation, uranium costs half what it did in the early seventies (Keeny, 1998).

Supporters of reprocessing argue that Carter's attempt to set an example for the world has failed and that the end of the Cold War has decreased the danger of nuclear weapons proliferation. They also point out that any country that really wanted reprocessing for energy purposes would have the incentive to allow international monitoring which would prevent diversion. Also, reactor grade plutonium is not ideal for weapons because it has a high concentration of the heavier isotopes P-240, P-241, and P-242. P-239 is the best for nuclear weapons. The heavier isotopes give off heat, causing inevitable cooling and storage problems for those who attempted to use reactor grade plutonium for weapons purposes. Additionally, prohibiting reprocessing affects only one possible route to nuclear weapons proliferation. Other routes are cheaper, more reliable, and easier to conceal. One argument against reprocessing is that it is not economical, since uranium prices are so low. Supporters of reprocessing respond by saying that the fuel is actually a very small part of the total cost of producing electricity from nuclear reactions and that the utility companies who build and maintain the reactors should be able to decide for themselves if reprocessing is worthwhile. The United States hoped to set an example for the world by choosing not to reprocess. However, the world has not followed this example. Breeder reactors operate safely in other parts of the world while the United States falls behind in nuclear technology. According to Dr. A. David Rossin (1998), former President of the American Nuclear Society and former Director of the Nuclear Safety Analysis Center, "The Clinton Administration has accepted the reasoning of the Carter years. This rigidity…undermined our ability to work effectively with other nations toward disposition of excess nuclear weapons." With the ending of the Cold War, it is now time to take another look at reprocessing.

High level waste shipping
If all of the high level nuclear waste is eventually going to be stored at one location or reprocessed, then it must be transported safely. Opponents of nuclear power call any transport of high level nuclear waste a "mobile Chernobyl." Nevada Senator Harry Reid remarked, "There could be accidents. Terrorists could get their hands on these shipments. And there's no reason to move it. They can leave it where it is safely for the next 100 years" (Lloyd, 1998, p.4). Senator Reid apparently disagrees with the consensus among scientists that the safest form of storage of high level nuclear waste is deep underground, not above ground like it is now. Senator Reid and those like him who raise objections to the transport of nuclear waste are just plain wrong. High level waste can be shipped safely. The typical shipping container consists of a stainless steel cylinder surrounding the used fuel rods, several inches of lead shielding, and two more layers of steel. They are five feet in diameter and seventeen feet long. The shipping containers have been put through several tests and have passed with flying colors. The containers were first put on a flatbed truck, and the truck was run into a concrete wall at 60 miles per hour and then at 80 miles per hour. Next, the containers were put on a different flatbed truck and broadsided by a 120-ton train travelling 80 miles per hour. After this, they were burned in jet fuel for an hour and a half at temperatures exceeding 2000oF (NEI: Shipping, 1998).

What are we going to do when we are faced with the inevitable energy crisis early next century? Will we keep burning fossil fuels and polluting the environment, or will we choose an alternative energy source? All forms of energy production, including nuclear power, have their pros and cons. However, we will be forced to make decisions about how to provide electricity as our needs increase. Nuclear energy is safe, clean, and cheap, and it provides the answers to our energy problems. We must not allow misinformation and scare tactics to influence those making the important energy decisions. We, as Christian biologists, should support nuclear power as a practical way to solve our energy problems while preserving the earth.

Works Cited

Keeny, S.M. (1998). FRONTLINE: nuclear reaction: Plutonium reprocessing. (25 Oct 1998).

Lloyd, J. (27 Feb 1998). Can nuclear waste be safely moved? Christian Science Monitor. p4. Palni.…fulltext.html:bad=html/fulltext.html.

Nuclear Energy Institute. (1998). NEI: The nuclear energy story: The energy plant. (25 Oct 1998).

Nuclear Energy Institute. (1998). NEI: The nuclear energy story: High-level waste. (25 Oct 1998).

Nuclear Energy Institute (1998). NEI: The nuclear energy story: Nuclear fuel. (25 Oct 1998).

Nuclear Energy Institute. (1998). NEI: The nuclear energy story: Safety. (25 Oct 1998).

Nuclear Energy Institute (1998). NEI: The nuclear energy story: Shipping. (26 Oct 1998).

Nuclear Energy: Power for people. Booklet from Nuclear Energy Institute.

Rossin, D.A. (1998). FRONTLINE: nuclear reaction: policy on reprocessing. (25 Oct 1998).

Taylor, L.S. (1996). LST Intro. (25 Oct 1998).